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Kapur NK, Kanwar MK, Yousefzai R, Bhimiraj A, Farber H, Esposito ML, Kiernan MS, John KJ, Burkhoff D. Mechanical Preload Reduction: Harnessing a Cornerstone of Heart Failure Management to Improve Clinical Outcomes. ASAIO J 2024:00002480-990000000-00499. [PMID: 38829983 DOI: 10.1097/mat.0000000000002240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024] Open
Abstract
Decongestion is a cornerstone therapeutic goal for those presenting with decompensated heart failure. Current approaches to clinical decongestion include reducing cardiac preload, which is typically limited to diuretics and hemofiltration. Several new technologies designed to mechanically reduce cardiac preload are in development. In this review, we discuss the pathophysiology of decompensated heart failure; the central role of targeting cardiac preload; emerging mechanical preload reduction technologies; and potential application of these devices.
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Affiliation(s)
- Navin K Kapur
- From the Department of Cardiology, Tufts Medical Center, Boston, Massachusetts
| | - Manreet K Kanwar
- Department of Cardiology, Cardiovascular Institute at Allegheny Health Network, Pittsburgh, Pennsylvania
| | - Rayan Yousefzai
- Department of Cardiology, Houston Methodist Research Institute, Houston, Texas
| | - Arvind Bhimiraj
- Department of Cardiology, Houston Methodist Research Institute, Houston, Texas
| | - Harrison Farber
- From the Department of Cardiology, Tufts Medical Center, Boston, Massachusetts
| | - Michele L Esposito
- Department of Cardiology, Medical University of South Carolina, Charleston, South Carolina
| | - Michael S Kiernan
- From the Department of Cardiology, Tufts Medical Center, Boston, Massachusetts
| | - Kevin J John
- From the Department of Cardiology, Tufts Medical Center, Boston, Massachusetts
| | - Daniel Burkhoff
- Department of Cardiology, The Cardiovascular Research Foundation, New York, New York
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Labus J, Foit A, Mehler O, Rahmanian P, Böttiger BW, Wetsch WA, Mathes A. Intraoperative Noninvasive Left Ventricular Myocardial Work Indices in Patients Undergoing On-Pump Coronary Artery Bypass Surgery. J Cardiothorac Vasc Anesth 2023; 37:221-231. [PMID: 36404229 DOI: 10.1053/j.jvca.2022.10.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/13/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVES Noninvasive echocardiographic analysis of left ventricular (LV) myocardial work (MW) enables insights into cardiac mechanics, contractility, and efficacy beyond ejection fraction (EF) and global longitudinal strain (GLS). However, there are limited perioperative data on patients undergoing coronary artery bypass graft (CABG) surgery. The authors aimed to describe the feasibility and the intraoperative course of this novel assessment tool of ventricular function in these patients, and compare it to conventional 2-dimensional (2D) and 3-dimensional (3D) echocardiographic parameters and strain analysis. DESIGN A prospective observational study. SETTING At a single university hospital. PARTICIPANTS Twenty-five patients with preoperative preserved LV and right ventricular function, sinus rhythm, without significant heart valve disease or pulmonary hypertension, and an uncomplicated intraoperative course scheduled for isolated on-pump CABG surgery. INTERVENTIONS Transesophageal echocardiography (TEE) was performed intraoperatively after the induction of anesthesia (T1), after termination of cardiopulmonary bypass (T2), and after sternal closure (T3). All measurements were performed under stable hemodynamic conditions, in sinus rhythm or atrial pacing, and vasopressor support with norepinephrine ≤ 0.1 µg/kg/min. MEASUREMENTS AND MAIN RESULTS The EchoPAC v204 software (GE Vingmed Ultrasound AS, Norway) was used for analysis of 2D and 3D LVEF, LV GLS, LV global work index (GWI), LV global constructive work (GCW), LV global wasted work (GWW), and LV global work efficiency (GWE). The MW analysis was feasible in all patients. Although there was no significant difference in the values of 2D and 3D EF during the intraoperative interval, GLS deteriorated significantly after CABG compared to assessment after induction of anesthesia (T1 v T2, -13.3 ± 3.0% v -11.6 ± 3.1%; p = 0.012). The GWI declined significantly after surgery (T1 v T2, 1,224 ± 312 mmHg% v 940 ± 267 mmHg%; p < 0.001), as well as GCW (T1 v T2, 1,460 ± 312 mmHg% v 1,244 ± 336 mmHg%; p = 0.005). The GWW increased after CABG (T1 v T2, 143 mmHg% (IQR 99-183) v 251 mmHg% (IQR 179-361); p < 0.001), and GWE decreased (T1 v T2, 89% (IQR 85-92) v 80% (IQR 75-87); p < 0.001). There were no significant changes in the values of 2D and 3D EF, GLS, GWI, GCW, GWW, and GWE before and after sternal closure (T2 v T3). CONCLUSION The intraoperative analysis of noninvasive echocardiographically-assessed LV MW indices is feasible. In the short-term period after uncomplicated on-pump CABG, GLS, as well as global and constructive MW, decreased, whereas wasted work increased, resulting in a less efficient left ventricle. None of these aspects was detected by conventional echocardiographic parameters. Therefore, strain and MW analysis might be more sensitive parameters in detecting myocardial dysfunction by TEE in the perioperative setting, adding information on perioperative cardiac energetics.
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Affiliation(s)
- Jakob Labus
- Department of Anesthesiology and Intensive Care Medicine, University Hospital of Cologne, and Faculty of Medicine, University of Cologne, Cologne, Germany.
| | - André Foit
- Department of Anesthesiology and Intensive Care Medicine, University Hospital of Cologne, and Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Oliver Mehler
- Department of Anesthesiology and Intensive Care Medicine, University Hospital of Cologne, and Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Parwis Rahmanian
- Department of Cardiothoracic Surgery, Heart Center, University Hospital of Cologne, and Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Bernd W Böttiger
- Department of Anesthesiology and Intensive Care Medicine, University Hospital of Cologne, and Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Wolfgang A Wetsch
- Department of Anesthesiology and Intensive Care Medicine, University Hospital of Cologne, and Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Alexander Mathes
- Department of Anesthesiology and Intensive Care Medicine, University Hospital of Cologne, and Faculty of Medicine, University of Cologne, Cologne, Germany
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Longitudinal Validation of Right Ventricular Pressure Monitoring for the Assessment of Right Ventricular Systolic Dysfunction in a Large Animal Ischemic Model. Crit Care Explor 2023; 5:e0847. [PMID: 36699251 PMCID: PMC9851694 DOI: 10.1097/cce.0000000000000847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Right ventricular (RV) dysfunction is a major cause of morbidity and mortality in intensive care and cardiac surgery. Early detection of RV dysfunction may be facilitated by continuous monitoring of RV waveform obtained from a pulmonary artery catheter. The objective is to evaluate the extent to which RV pressure monitoring can detect changes in RV systolic performance assess by RV end-systolic elastance (Ees) following the development of an acute RV ischemic in a porcine model. HYPOTHESIS RV pressure monitoring can detect changes in RV systolic performance assess by RV Ees following the development of an acute RV ischemic model. METHODS AND MODELS Acute ischemic RV dysfunction was induced by progressive embolization of microsphere in the right coronary artery to mimic RV dysfunction clinically experienced during cardiopulmonary bypass separation caused by air microemboli. RV hemodynamic performance was assessed using RV pressure waveform-derived parameters and RV Ees obtained using a conductance catheter during inferior vena cava occlusions. RESULTS Acute ischemia resulted in a significant reduction in RV Ees from 0.26 mm Hg/mL (interquartile range, 0.16-0.32 mm Hg/mL) to 0.14 mm Hg/mL (0.11-0.19 mm Hg/mL; p < 0.010), cardiac output from 6.3 L/min (5.7-7 L/min) to 4.5 (3.9-5.2 L/min; p = 0.007), mean systemic arterial pressure from 72 mm Hg (66-74 mm Hg) to 51 mm Hg (46-56 mm Hg; p < 0.001), and mixed venous oxygen saturation from 65% (57-72%) to 41% (35-45%; p < 0.001). Linear mixed-effect model analysis was used to assess the relationship between Ees and RV pressure-derived parameters. The reduction in RV Ees best correlated with a reduction in RV maximum first derivative of pressure during isovolumetric contraction (dP/dtmax) and single-beat RV Ees. Adjusting RV dP/dtmax for heart rate resulted in an improved surrogate of RV Ees. INTERPRETATION AND CONCLUSIONS Stepwise decreases in RV Ees during acute ischemic RV dysfunction were accurately tracked by RV dP/dtmax derived from the RV pressure waveform.
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Long-term prognostic impact of paravalvular leakage on coronary artery disease requires patient-specific quantification of hemodynamics. Sci Rep 2022; 12:21357. [PMID: 36494362 PMCID: PMC9734172 DOI: 10.1038/s41598-022-21104-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 09/22/2022] [Indexed: 12/13/2022] Open
Abstract
Transcatheter aortic valve replacement (TAVR) is a frequently used minimally invasive intervention for patient with aortic stenosis across a broad risk spectrum. While coronary artery disease (CAD) is present in approximately half of TAVR candidates, correlation of post-TAVR complications such as paravalvular leakage (PVL) or misalignment with CAD are not fully understood. For this purpose, we developed a multiscale computational framework based on a patient-specific lumped-parameter algorithm and a 3-D strongly-coupled fluid-structure interaction model to quantify metrics of global circulatory function, metrics of global cardiac function and local cardiac fluid dynamics in 6 patients. Based on our findings, PVL limits the benefits of TAVR and restricts coronary perfusion due to the lack of sufficient coronary blood flow during diastole phase (e.g., maximum coronary flow rate reduced by 21.73%, 21.43% and 21.43% in the left anterior descending (LAD), left circumflex (LCX) and right coronary artery (RCA) respectively (N = 6)). Moreover, PVL may increase the LV load (e.g., LV load increased by 17.57% (N = 6)) and decrease the coronary wall shear stress (e.g., maximum wall shear stress reduced by 20.62%, 21.92%, 22.28% and 25.66% in the left main coronary artery (LMCA), left anterior descending (LAD), left circumflex (LCX) and right coronary artery (RCA) respectively (N = 6)), which could promote atherosclerosis development through loss of the physiological flow-oriented alignment of endothelial cells. This study demonstrated that a rigorously developed personalized image-based computational framework can provide vital insights into underlying mechanics of TAVR and CAD interactions and assist in treatment planning and patient risk stratification in patients.
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Kapur NK, Kiernan MS, Gorgoshvili I, Yousefzai R, Vorovich EE, Tedford RJ, Sauer AJ, Abraham J, Resor CD, Kimmelstiel CD, Benzuly KH, Steinberg DH, Messer J, Burkhoff D, Karas RH. Intermittent Occlusion of the Superior Vena Cava to Improve Hemodynamics in Patients With Acutely Decompensated Heart Failure: The VENUS-HF Early Feasibility Study. Circ Heart Fail 2022; 15:e008934. [PMID: 35000420 DOI: 10.1161/circheartfailure.121.008934] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Reducing congestion remains a primary target of therapy for acutely decompensated heart failure. The VENUS-HF EFS (VENUS-Heart Failure Early Feasibility Study) is the first clinical trial testing intermittent occlusion of the superior vena cava with the preCARDIA system, a catheter mounted balloon and pump console, to improve decongestion in acutely decompensated heart failure. METHODS In a multicenter, prospective, single-arm exploratory safety and feasibility trial, 30 patients with acutely decompensated heart failure were assigned to preCARDIA therapy for 12 or 24 hours. The primary safety outcome was a composite of major adverse cardiovascular and cerebrovascular events through 30 days. Secondary end points included technical success defined as successful preCARDIA placement, treatment, and removal and reduction in right atrial and pulmonary capillary wedge pressure. Other efficacy measures included urine output and patient-reported symptoms. RESULTS Thirty patients were enrolled and assigned to receive the preCARDIA system. Freedom from device- or procedure-related major adverse events was observed in 100% (n=30/30) of patients. The system was successfully placed, activated and removed after 12 (n=6) or 24 hours (n=23) in 97% (n=29/30) of patients. Compared with baseline values, right atrial pressure decreased by 34% (17±4 versus 11±5 mm Hg, P<0.001) and pulmonary capillary wedge pressure decreased by 27% (31±8 versus 22±9 mm Hg, P<0.001). Compared with pretreatment values, urine output and net fluid balance increased by 130% and 156%, respectively, with up to 24 hours of treatment (P<0.01). CONCLUSIONS We report the first-in-human experience of intermittent superior vena cava occlusion using the preCARDIA system to reduce congestion in acutely decompensated heart failure. PreCARDIA treatment for up to 24 hours was well tolerated without device- or procedure-related serious or major adverse events and associated with reduced filling pressures and increased urine output. These results support future studies characterizing the clinical utility of the preCARDIA system. REGISTRATION URL: https://www.clinicaltrials.gov; Unique identifier: NCT03836079.
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Affiliation(s)
- Navin K Kapur
- Tufts Medical Center, Boston, MA (N.K.K., M.S.K., C.D.R., C.D.K., R.H.K.)
| | - Michael S Kiernan
- Tufts Medical Center, Boston, MA (N.K.K., M.S.K., C.D.R., C.D.K., R.H.K.)
| | | | | | | | - Ryan J Tedford
- Medical University of South Carolina, Charleston (R.J.T., D.H.S.)
| | | | | | - Charles D Resor
- Tufts Medical Center, Boston, MA (N.K.K., M.S.K., C.D.R., C.D.K., R.H.K.)
| | | | - Keith H Benzuly
- Northwestern Memorial Hospital, Chicago, IL (E.E.V., K.H.B.)
| | | | | | - Daniel Burkhoff
- Cardiovascular Research Foundation, West Harrison, NY (D.B.)
| | - Richard H Karas
- Tufts Medical Center, Boston, MA (N.K.K., M.S.K., C.D.R., C.D.K., R.H.K.)
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Baiocchi M, Barsoum S, Khodaei S, de la Torre Hernandez JM, Valentino SE, Dunford EC, MacDonald MJ, Keshavarz-Motamed Z. Effects of Choice of Medical Imaging Modalities on a Non-invasive Diagnostic and Monitoring Computational Framework for Patients With Complex Valvular, Vascular, and Ventricular Diseases Who Undergo Transcatheter Aortic Valve Replacement. Front Bioeng Biotechnol 2021; 9:643453. [PMID: 34307316 PMCID: PMC8297508 DOI: 10.3389/fbioe.2021.643453] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/19/2021] [Indexed: 11/13/2022] Open
Abstract
Due to the high individual differences in the anatomy and pathophysiology of patients, planning individualized treatment requires patient-specific diagnosis. Indeed, hemodynamic quantification can be immensely valuable for accurate diagnosis, however, we still lack precise diagnostic methods for numerous cardiovascular diseases including complex (and mixed) valvular, vascular, and ventricular interactions (C3VI) which is a complicated situation made even more challenging in the face of other cardiovascular pathologies. Transcatheter aortic valve replacement (TAVR) is a new less invasive intervention and is a growing alternative for patients with aortic stenosis. In a recent paper, we developed a non-invasive and Doppler-based diagnostic and monitoring computational mechanics framework for C3VI, called C3VI-DE that uses input parameters measured reliably using Doppler echocardiography. In the present work, we have developed another computational-mechanics framework for C3VI (called C3VI-CT). C3VI-CT uses the same lumped-parameter model core as C3VI-DE but its input parameters are measured using computed tomography and a sphygmomanometer. Both frameworks can quantify: (1) global hemodynamics (metrics of cardiac function); (2) local hemodynamics (metrics of circulatory function). We compared accuracy of the results obtained using C3VI-DE and C3VI-CT against catheterization data (gold standard) using a C3VI dataset (N = 49) for patients with C3VI who undergo TAVR in both pre and post-TAVR with a high variability. Because of the dataset variability and the broad range of diseases that it covers, it enables determining which framework can yield the most accurate results. In contrast with C3VI-CT, C3VI-DE tracks both the cardiac and vascular status and is in great agreement with cardiac catheter data.
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Affiliation(s)
- Melissa Baiocchi
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, Canada
| | - Shirley Barsoum
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, Canada
| | - Seyedvahid Khodaei
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, Canada
| | | | | | - Emily C Dunford
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada
| | | | - Zahra Keshavarz-Motamed
- Department of Mechanical Engineering, McMaster University, Hamilton, ON, Canada.,School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada.,School of Computational Science and Engineering, McMaster University, Hamilton, ON, Canada
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The non-invasive assessment of myocardial work by pressure-strain analysis: clinical applications. Heart Fail Rev 2021; 27:1261-1279. [PMID: 34041679 PMCID: PMC9197903 DOI: 10.1007/s10741-021-10119-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/28/2021] [Indexed: 11/10/2022]
Abstract
Pressure–volume (PV) analysis is the most comprehensive way to describe cardiac function, giving insights into cardiac mechanics and energetics. However, PV analysis still remains a highly invasive and time-consuming method, preventing it from integration into clinical practice. Most of the echocardiographic parameters currently used in the clinical routine to characterize left ventricular (LV) systolic function, such as LV ejection fraction and LV global longitudinal strain, do not take the pressure developed within the LV into account and therefore fall too short in describing LV function as a hydraulic pump. Recently, LV pressure-strain analysis has been introduced as a new technique to assess myocardial work in a non-invasive fashion. This new method showed new insights in comparison to invasive measurements and was validated in different cardiac pathologies, e.g., for the detection of coronary artery disease, cardiac resynchronization therapy (CRT)-response prediction, and different forms of heart failure. Non-invasively assessed myocardial work may play a major role in guiding therapies and estimating prognosis. However, its incremental prognostic validity in comparison to common echocardiographic parameters remains unclear. This review aims to provide an overview of pressure-strain analysis, including its current application in the clinical arena, as well as potential fields of exploitation.
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Kaiser DW, Platzer P, Miyashiro K, Canfield J, Patel R, Liu D, St. Goar F, Kaiser CA. First-in-Human Experience of Mechanical Preload Control in Patients With HFpEF During Exercise. JACC Basic Transl Sci 2021; 6:189-198. [PMID: 33778208 PMCID: PMC7987536 DOI: 10.1016/j.jacbts.2020.12.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/03/2020] [Accepted: 12/03/2020] [Indexed: 01/08/2023]
Abstract
Heart failure patients demonstrate pulmonary hypertension during exertion that correlates with limitations in exercise capacity. Titrated partial occlusion of the IVC through balloon inflation (mechanical preload control) during exercise significantly reduced PA pressure by 25% (from 68 ± 7 mm Hg to 51 ± 7 mm Hg) with no significant reduction in peak VO2 (from 16.4 ± 5.8 ml/kg/min to 16.2 ± 4.0 ml/kg/min) or cardiac output (14.4 ± 5.9 l/min to 12.8 ± 2.9 l/min). Mechanical preload control trended toward longer exercise times and significantly reduced respiratory rate at matched exercise, suggesting that pulmonary pressures directly contribute to exercise limitations and hyperventilation in heart failure patients. Mechanical preload control may serve as a novel research and treatment strategy for heart failure patients.
Exercise intolerance remains one of the major factors determining quality of life in heart failure patients. In 6 patients with heart failure with preserved ejection fraction (HFpEF) undergoing invasive cardiopulmonary exercise testing, balloon inflation within the inferior vena cava (IVC) was performed during exercise to reduce and maintain pulmonary arterial (PA) pressures. Partial IVC occlusion significantly reduced PA pressures without reducing cardiac output. Partial IVC occlusion significantly reduced respiratory rate at matched levels of exercise. These findings highlight the importance of pulmonary pressures in the pathophysiology of HFpEF and suggest that therapies targeting hemodynamics may improve symptoms and exercise capacity in these patients.
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Affiliation(s)
- Daniel W. Kaiser
- Department of Respiratory Therapy, El Camino Hospital, Mountain View, California
- Department of Cardiovascular Medicine, Saint Thomas Hospital, Nashville, Tennessee, USA
- CardioFlow Technologies, Nashville, Tennessee, USA
- Address for correspondence: Dr. Daniel W Kaiser, Saint Thomas Hospital, 301 21st Avenue, N #100, Nashville, Tennessee 37203, USA.
| | - Patrick Platzer
- Department of Cardiovascular Medicine, Saint Thomas Hospital, Nashville, Tennessee, USA
| | | | - James Canfield
- Department of Respiratory Therapy, El Camino Hospital, Mountain View, California
| | - Rupal Patel
- Department of Respiratory Therapy, El Camino Hospital, Mountain View, California
| | - Dandan Liu
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Frederick St. Goar
- Department of Respiratory Therapy, El Camino Hospital, Mountain View, California
| | - Clayton A. Kaiser
- Department of Cardiovascular Medicine, Saint Thomas Hospital, Nashville, Tennessee, USA
- CardioFlow Technologies, Nashville, Tennessee, USA
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Yamagishi M, Tamaki N, Akasaka T, Ikeda T, Ueshima K, Uemura S, Otsuji Y, Kihara Y, Kimura K, Kimura T, Kusama Y, Kumita S, Sakuma H, Jinzaki M, Daida H, Takeishi Y, Tada H, Chikamori T, Tsujita K, Teraoka K, Nakajima K, Nakata T, Nakatani S, Nogami A, Node K, Nohara A, Hirayama A, Funabashi N, Miura M, Mochizuki T, Yokoi H, Yoshioka K, Watanabe M, Asanuma T, Ishikawa Y, Ohara T, Kaikita K, Kasai T, Kato E, Kamiyama H, Kawashiri M, Kiso K, Kitagawa K, Kido T, Kinoshita T, Kiriyama T, Kume T, Kurata A, Kurisu S, Kosuge M, Kodani E, Sato A, Shiono Y, Shiomi H, Taki J, Takeuchi M, Tanaka A, Tanaka N, Tanaka R, Nakahashi T, Nakahara T, Nomura A, Hashimoto A, Hayashi K, Higashi M, Hiro T, Fukamachi D, Matsuo H, Matsumoto N, Miyauchi K, Miyagawa M, Yamada Y, Yoshinaga K, Wada H, Watanabe T, Ozaki Y, Kohsaka S, Shimizu W, Yasuda S, Yoshino H. JCS 2018 Guideline on Diagnosis of Chronic Coronary Heart Diseases. Circ J 2021; 85:402-572. [PMID: 33597320 DOI: 10.1253/circj.cj-19-1131] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
| | - Nagara Tamaki
- Department of Radiology, Kyoto Prefectural University of Medicine Graduate School
| | - Takashi Akasaka
- Department of Cardiovascular Medicine, Wakayama Medical University
| | - Takanori Ikeda
- Department of Cardiovascular Medicine, Toho University Graduate School
| | - Kenji Ueshima
- Center for Accessing Early Promising Treatment, Kyoto University Hospital
| | - Shiro Uemura
- Department of Cardiology, Kawasaki Medical School
| | - Yutaka Otsuji
- Second Department of Internal Medicine, University of Occupational and Environmental Health, Japan
| | - Yasuki Kihara
- Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences
| | - Kazuo Kimura
- Division of Cardiology, Yokohama City University Medical Center
| | - Takeshi Kimura
- Department of Cardiovascular Medicine, Kyoto University Graduate School
| | | | | | - Hajime Sakuma
- Department of Radiology, Mie University Graduate School
| | | | - Hiroyuki Daida
- Department of Cardiovascular Medicine, Juntendo University Graduate School
| | | | - Hiroshi Tada
- Department of Cardiovascular Medicine, University of Fukui
| | | | - Kenichi Tsujita
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University
| | | | - Kenichi Nakajima
- Department of Functional Imaging and Artificial Intelligence, Kanazawa Universtiy
| | | | - Satoshi Nakatani
- Division of Functional Diagnostics, Department of Health Sciences, Osaka University Graduate School of Medicine
| | | | - Koichi Node
- Department of Cardiovascular Medicine, Saga University
| | - Atsushi Nohara
- Division of Clinical Genetics, Ishikawa Prefectural Central Hospital
| | | | | | - Masaru Miura
- Department of Cardiology, Tokyo Metropolitan Children's Medical Center
| | | | | | | | - Masafumi Watanabe
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University
| | - Toshihiko Asanuma
- Division of Functional Diagnostics, Department of Health Sciences, Osaka University Graduate School
| | - Yuichi Ishikawa
- Department of Pediatric Cardiology, Fukuoka Children's Hospital
| | - Takahiro Ohara
- Division of Community Medicine, Tohoku Medical and Pharmaceutical University
| | - Koichi Kaikita
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University
| | - Tokuo Kasai
- Department of Cardiology, Uonuma Kinen Hospital
| | - Eri Kato
- Department of Cardiovascular Medicine, Department of Clinical Laboratory, Kyoto University Hospital
| | | | - Masaaki Kawashiri
- Department of Cardiovascular and Internal Medicine, Kanazawa University
| | - Keisuke Kiso
- Department of Diagnostic Radiology, Tohoku University Hospital
| | - Kakuya Kitagawa
- Department of Advanced Diagnostic Imaging, Mie University Graduate School
| | - Teruhito Kido
- Department of Radiology, Ehime University Graduate School
| | | | | | | | - Akira Kurata
- Department of Radiology, Ehime University Graduate School
| | - Satoshi Kurisu
- Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences
| | - Masami Kosuge
- Division of Cardiology, Yokohama City University Medical Center
| | - Eitaro Kodani
- Department of Internal Medicine and Cardiology, Nippon Medical School Tama Nagayama Hospital
| | - Akira Sato
- Department of Cardiology, University of Tsukuba
| | - Yasutsugu Shiono
- Department of Cardiovascular Medicine, Wakayama Medical University
| | - Hiroki Shiomi
- Department of Cardiovascular Medicine, Kyoto University Graduate School
| | - Junichi Taki
- Department of Nuclear Medicine, Kanazawa University
| | - Masaaki Takeuchi
- Department of Laboratory and Transfusion Medicine, Hospital of the University of Occupational and Environmental Health, Japan
| | | | - Nobuhiro Tanaka
- Department of Cardiology, Tokyo Medical University Hachioji Medical Center
| | - Ryoichi Tanaka
- Department of Reconstructive Oral and Maxillofacial Surgery, Iwate Medical University
| | | | | | - Akihiro Nomura
- Innovative Clinical Research Center, Kanazawa University Hospital
| | - Akiyoshi Hashimoto
- Department of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University
| | - Kenshi Hayashi
- Department of Cardiovascular Medicine, Kanazawa University Hospital
| | - Masahiro Higashi
- Department of Radiology, National Hospital Organization Osaka National Hospital
| | - Takafumi Hiro
- Division of Cardiology, Department of Medicine, Nihon University
| | | | - Hitoshi Matsuo
- Department of Cardiovascular Medicine, Gifu Heart Center
| | - Naoya Matsumoto
- Division of Cardiology, Department of Medicine, Nihon University
| | | | | | | | - Keiichiro Yoshinaga
- Department of Diagnostic and Therapeutic Nuclear Medicine, Molecular Imaging at the National Institute of Radiological Sciences
| | - Hideki Wada
- Department of Cardiology, Juntendo University Shizuoka Hospital
| | - Tetsu Watanabe
- Department of Cardiology, Pulmonology, and Nephrology, Yamagata University
| | - Yukio Ozaki
- Department of Cardiology, Fujita Medical University
| | - Shun Kohsaka
- Department of Cardiology, Keio University School of Medicine
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School
| | - Satoshi Yasuda
- Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine
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Tran T, Muralidhar A, Hunter K, Buchanan C, Coe G, Hieda M, Tompkins C, Zipse M, Spotts MJ, Laing SG, Fosmark K, Hoffman J, Ambardekar AV, Wolfel EE, Lawley J, Levine B, Kohrt WM, Pal J, Cornwell WK. Right ventricular function and cardiopulmonary performance among patients with heart failure supported by durable mechanical circulatory support devices. J Heart Lung Transplant 2021; 40:128-137. [PMID: 33281029 DOI: 10.1016/j.healun.2020.11.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 10/15/2020] [Accepted: 11/18/2020] [Indexed: 10/22/2022] Open
Abstract
BACKGROUND Patients with continuous-flow left ventricular assist devices (CF-LVADs) experience limitations in functional capacity and frequently, right ventricular (RV) dysfunction. We sought to characterize RV function in the context of global cardiopulmonary performance during exercise in this population. METHODS A total of 26 patients with CF-LVAD (aged 58 ± 11 years, 23 males) completed a hemodynamic assessment with either conductance catheters (Group 1, n = 13) inserted into the right ventricle to generate RV pressure‒volume loops or traditional Swan‒Ganz catheters (Group 2, n = 13) during invasive cardiopulmonary exercise testing. Hemodynamics were collected at rest, 2 sub-maximal levels of exercise, and peak effort. Breath-by-breath gas exchange parameters were collected by indirect calorimetry. Group 1 participants also completed an invasive ramp test during supine rest to determine the impact of varying levels of CF-LVAD support on RV function. RESULTS In Group 1, pump speed modulations minimally influenced RV function. During upright exercise, there were modest increases in RV contractility during sub-maximal exercise, but there were no appreciable increases at peak effort. Ventricular‒arterial coupling was preserved throughout the exercise. In Group 2, there were large increases in pulmonary arterial, left-sided filling, and right-sided filling pressures during sub-maximal and peak exercises. Among all participants, the cardiac output‒oxygen uptake relationship was preserved at 5.8:1. Ventilatory efficiency was severely abnormal at 42.3 ± 11.6. CONCLUSIONS Patients with CF-LVAD suffer from limited RV contractile reserve; marked elevations in pulmonary, left-sided filling, and right-sided filling pressures during exercise; and severe ventilatory inefficiency. These findings explain mechanisms for persistent reductions in functional capacity in this patient population.
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Affiliation(s)
- Tomio Tran
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Akshay Muralidhar
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Kendall Hunter
- Department of Bioengineering, Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Cullen Buchanan
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Greg Coe
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Michinari Hieda
- Department of Medicine, Division of Cardiology, University of Texas Southwestern Medical Campus, Dallas, Texas; Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas Texas
| | - Christine Tompkins
- Division of Cardiology, Department of Medicine, Emory University, Atlanta, Georgia
| | - Matthew Zipse
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Melanie J Spotts
- Clinical Translational Research Center, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Stephanie G Laing
- Clinical Translational Research Center, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Kristina Fosmark
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Jordan Hoffman
- Department of Cardiac Surgery, Vanderbilt University, Nashville, Tennessee
| | - Amrut V Ambardekar
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Eugene E Wolfel
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Justin Lawley
- Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Benjamin Levine
- Department of Medicine, Division of Cardiology, University of Texas Southwestern Medical Campus, Dallas, Texas; Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas Texas
| | - Wendy M Kohrt
- Division of Geriatric Medicine, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Jay Pal
- Department of Cardiothoracic Surgery, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - William K Cornwell
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado.
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11
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Korn L, Dahlmanns S, Leonhardt S, Walter M. Improved Estimation of Left Ventricular Volume from Electric Field Modeling. JOURNAL OF ELECTRICAL BIOIMPEDANCE 2021; 12:125-134. [PMID: 35069948 PMCID: PMC8713389 DOI: 10.2478/joeb-2021-0015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Indexed: 06/14/2023]
Abstract
Volume measurement is beneficial in left ventricular assist device (LVAD) therapy to quantify patient demand. In principle, an LVAD could provide a platform that allows bioimpedance measurements inside the ventricle without requiring additional implants. Conductance measured by the LVAD can then be used to estimate the ventricular radius, which can be applied to calculate ventricular volume. However, established methods that estimate radius from conductance require elaborate individual calibration or show low accuracy. This study presents two analytical calculation methods to estimate left ventricular radius from conductance using electric field theory. These methods build on the established method of Wei, now considering the dielectric properties of muscle and background tissue, the refraction of the electric field at the blood-muscle boundary, and the changes of the electric field caused by the measurements. The methods are validated in five glass containers of different radius. Additional bioimpedance measurements are performed in in-vitro models that replicate the left ventricle's shape and conductive properties. The proposed analytical calculation methods estimate the radii of the containers and the in-vitro models with higher accuracy and precision than Wei's method. The lead method performs excellently in glass cylinders over a wide range of radii (bias: 1.66%-2.48%, limits of agreement < 16.33%) without calibration to specific geometries.
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Affiliation(s)
- Leonie Korn
- Medical Information Technology, RWTH Aachen University, Aachen, Germany
| | - Stephan Dahlmanns
- Medical Information Technology, RWTH Aachen University, Aachen, Germany
| | - Steffen Leonhardt
- Medical Information Technology, RWTH Aachen University, Aachen, Germany
| | - Marian Walter
- Medical Information Technology, RWTH Aachen University, Aachen, Germany
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12
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Omori T, Nakamori S, Fujimoto N, Ishida M, Kitagawa K, Ichikawa Y, Kumagai N, Kurita T, Imanaka-Yoshida K, Hiroe M, Sakuma H, Ito M, Dohi K. Myocardial Native T 1 Predicts Load-Independent Left Ventricular Chamber Stiffness In Patients With HFpEF. JACC Cardiovasc Imaging 2020; 13:2117-2128. [PMID: 32771571 DOI: 10.1016/j.jcmg.2020.05.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 05/12/2020] [Accepted: 05/15/2020] [Indexed: 11/20/2022]
Abstract
OBJECTIVES This study sought to evaluate the potential of cardiac magnetic resonance T1 mapping to detect load-independent left ventricular (LV) chamber stiffness by histological confirmation. BACKGROUND Accurate noninvasive diagnosis of LV diastolic dysfunction in heart failure with preserved ejection fraction (HFpEF) remains challenging. METHODS Nineteen HFpEF patients (14 female, 65 ± 16 years of age) without primary cardiomyopathy were prospectively enrolled. Cine, late gadolinium enhancement cardiac magnetic resonance, and triple-slice T1 mapping using a modified Look-Locker inversion recovery sequence were performed at 3-T. Extracellular volume (ECV) was quantified from pre- and post-contrast T1 values of the blood and myocardium with hematocrit correction. LV stiffness constant (beta) was assessed by calculating the slope of the end-diastolic pressure-volume relationship curve during vena cava occlusion. Biopsy samples were used for quantification of collagen volume fraction (CVF) and myocardial cell size. RESULTS Six patients showed focal scar on late gadolinium enhancement. There was no significant difference in histological CVF between patients with and without focal myocardial scarring (p = 0.2). Septal ECV rather than native T1 was a better surrogate marker for detecting histological CVF (r = 0.54; p = 0.02, and r = 0.44; p = 0.06, respectively). Global native T1 and ECV, but not native T1 and ECV in the septal myocardium, correlated well with the beta of passive LV stiffness, and had similar ability for predicting LV stiffness to histological CVF (r = 0.54, 0.50, 0.53, all p < 0.05, respectively). When the beta ≥0.054 was considered as moderately increased LV stiffness, global native T1 ≥1,362 ms provided 88% sensitivity and 64% specificity with the C-statistic of 0.81 (95% confidence interval: 0.56 to 0.95). CONCLUSIONS Myocardial native T1 provides comparable ability in predicting LV stiffness to ECV and histological CVF and may be useful for monitoring patients with HFpEF who have renal dysfunction, allergy to gadolinium, or wheezing that can simulate asthma. Our feasibility study shows the potential of native T1 to allow for insight of heterogeneous pathophysiology and better risk stratification of HFpEF.
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Affiliation(s)
- Taku Omori
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Mie, Japan
| | - Shiro Nakamori
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Mie, Japan.
| | - Naoki Fujimoto
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Mie, Japan
| | - Masaki Ishida
- Department of Radiology, Mie University Graduate School of Medicine, Mie, Japan
| | - Kakuya Kitagawa
- Department of Radiology, Mie University Graduate School of Medicine, Mie, Japan
| | - Yasutaka Ichikawa
- Department of Radiology, Mie University Graduate School of Medicine, Mie, Japan
| | - Naoto Kumagai
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Mie, Japan
| | - Tairo Kurita
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Mie, Japan
| | | | - Michiaki Hiroe
- Research Center for Matrix Biology, Mie University, Mie, Japan
| | - Hajime Sakuma
- Department of Radiology, Mie University Graduate School of Medicine, Mie, Japan
| | - Masaaki Ito
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Mie, Japan
| | - Kaoru Dohi
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Mie, Japan
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13
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Cornwell WK, Tran T, Cerbin L, Coe G, Muralidhar A, Hunter K, Altman N, Ambardekar AV, Tompkins C, Zipse M, Schulte M, O'Gean K, Ostertag M, Hoffman J, Pal JD, Lawley JS, Levine BD, Wolfel E, Kohrt WM, Buttrick P. New insights into resting and exertional right ventricular performance in the healthy heart through real-time pressure-volume analysis. J Physiol 2020; 598:2575-2587. [PMID: 32347547 DOI: 10.1113/jp279759] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 04/20/2020] [Indexed: 02/02/2024] Open
Abstract
KEY POINTS Despite growing interest in right ventricular form and function in diseased states, there is a paucity of data regarding characteristics of right ventricular function - namely contractile and lusitropic reserve, as well as ventricular-arterial coupling, in the healthy heart during rest, as well as submaximal and peak exercise. Pressure-volume analysis of the right ventricle, during invasive cardiopulmonary exercise testing, demonstrates that that the right heart has enormous contractile reserve, with a three- or fourfold increase in all metrics of contractility, as well as myocardial energy production and utilization. The healthy right ventricle also demonstrates marked augmentation in lusitropy, indicating that diastolic filling of the right heart is not passive. Rather, the right ventricle actively contributes to venous return during exercise, along with the muscle pump. Ventricular-arterial coupling is preserved during submaximal and peak exercise in the healthy heart. ABSTRACT Knowledge of right ventricular (RV) function has lagged behind that of the left ventricle and historically, the RV has even been referred to as a 'passive conduit' of lesser importance than its left-sided counterpart. Pressure-volume (PV) analysis is the gold standard metric of assessing ventricular performance. We recruited nine healthy sedentary individuals free of any cardiopulmonary disease (42 ± 12 years, 78 ± 11 kg), who completed invasive cardiopulmonary exercise testing during upright ergometry, while using conductance catheters inserted into the RV to generate real-time PV loops. Data were obtained at rest, two submaximal levels of exercise below ventilatory threshold, to simulate real-world scenarios/activities of daily living, and maximal effort. Breath-by-breath oxygen uptake was determined by indirect calorimetry. During submaximal and peak exercise, there were significant increases in all metrics of systolic function by three- to fourfold, including cardiac output, preload recruitable stroke work, and maximum rate of pressure change in the ventricle (dP/dtmax ), as well as energy utilization as determined by stroke work and pressure-volume area. Similarly, the RV demonstrated a significant, threefold increase in lusitropic reserve throughout exercise. Ventricular-arterial coupling, defined by the quotient of end-systolic elastance and effective arterial elastance, was preserved throughout all stages of exercise. Maximal pressures increased significantly during exercise, while end-diastolic volumes were essentially unchanged. Overall, these findings demonstrate that the healthy RV is not merely a passive conduit, but actively participates in cardiopulmonary performance during exercise by accessing an enormous amount of contractile and lusitropic reserve, ensuring that VA coupling is preserved throughout all stages of exercise.
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Affiliation(s)
- William K Cornwell
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Clinical and Translational Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Tomio Tran
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Lukasz Cerbin
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Greg Coe
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Akshay Muralidhar
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Kendall Hunter
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Natasha Altman
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Amrut V Ambardekar
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Christine Tompkins
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Matthew Zipse
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Margaret Schulte
- Clinical and Translational Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Katie O'Gean
- Clinical and Translational Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Morgan Ostertag
- Clinical and Translational Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Jordan Hoffman
- Department of Cardiothoracic Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Jay D Pal
- Department of Cardiothoracic Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Justin S Lawley
- Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Benjamin D Levine
- University of Texas Southwestern Medical Campus, Dallas, TX, USA
- Texas Health Presbyterian Hospital, Institute for Exercise and Environmental Medicine, Dallas, TX, USA
| | - Eugene Wolfel
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Wendy M Kohrt
- Clinical and Translational Research Center, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Department of Medicine, Division of Geriatric Medicine and Eastern Colorado VA Geriatric Research Education and Clinical Center, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Peter Buttrick
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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14
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A diagnostic, monitoring, and predictive tool for patients with complex valvular, vascular and ventricular diseases. Sci Rep 2020; 10:6905. [PMID: 32327673 PMCID: PMC7181740 DOI: 10.1038/s41598-020-63728-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 03/31/2020] [Indexed: 01/03/2023] Open
Abstract
Hemodynamics quantification is critically useful for accurate and early diagnosis, but we still lack proper diagnosticmethods for many cardiovascular diseases. Furthermore, as most interventions intend to recover the healthy condition, the ability to monitor and predict hemodynamics following interventions can have significant impacts on saving lives. Predictive methods are rare, enabling prediction of effects of interventions, allowing timely and personalized interventions and helping critical clinical decision making about life-threatening risks based on quantitative data. In this study, an innovative non-invasive imaged-based patient-specific diagnostic, monitoring and predictive tool (called C3VI-CMF) was developed, enabling quantifying (1) details of physiological flow and pressures through the heart and circulatory system; (2) heart function metrics. C3VI-CMF also predicts the breakdown of the effects of each disease constituents on the heart function. Presently, neither of these can be obtained noninvasively in patients and when invasive procedures are undertaken, the collected metrics cannot be by any means as complete as the ones C3VI-CMF provides. C3VI-CMF purposefully uses a limited number of noninvasive input parameters all of which can be measured using Doppler echocardiography and sphygmomanometer. Validation of C3VI-CMF, against cardiac catheterization in forty-nine patients with complex cardiovascular diseases, showed very good agreement with the measurements.
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15
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Non-Invasive Quantification of Ventricular Contractility, Arterial Elastic Function and Ventriculo-Arterial Coupling from a Single Diagnostic Encounter Using Simultaneous Arterial Tonometry and Magnetic Resonance Imaging. Cardiovasc Eng Technol 2020; 11:283-294. [DOI: 10.1007/s13239-020-00462-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 04/07/2020] [Indexed: 12/31/2022]
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16
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Ko B, Drakos SG, Ibrahim H, Kang TS, Thodou A, Bonios M, Taleb I, Welt FG. Percutaneous Mechanical Unloading Simultaneously With Reperfusion Induces Increased Myocardial Salvage in Experimental Acute Myocardial Infarction. Circ Heart Fail 2020; 13:e005893. [PMID: 31959013 DOI: 10.1161/circheartfailure.119.005893] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Despite advances in reperfusion times, patients presenting with acute myocardial infarction carry an unacceptably high rate of mortality and morbidity. Mechanical unloading of the left ventricle (LV) has been suggested to reduce infarct size after acute myocardial infarction. Although prior studies have investigated LV unloading during ischemia with a delay in reperfusion, little is known about the optimal timing for LV unloading in the setting of acute myocardial infarction. METHODS Studies were conducted in 17 adult Yorkshire swine weighing 67±5 kg. A coronary balloon was inflated in the mid left anterior descending for 60 minutes to induce a myocardial infarction. The coronary balloon was then deflated for 120 minutes (reperfusion). The animals were stratified into 3 groups: group 1 (control, reperfusion with no LV unloading, n=5), group 2 (LV unloading during ischemia with delayed reperfusion, n=6), and group 3 (simultaneous LV unloading and reperfusion, n=6). Staining the hearts with Evans blue and 2,3,5-triphenyltetrazolium chloride was used to identify the area at risk and the infarct area respectively. Infarct percent size was defined as the area of infarcted myocardium divided by the area at risk. RESULTS Of the 3 groups, group 3 demonstrated significantly smaller infarct percent size compared with controls (54.7±20.3% versus 22.2±13.4%; P=0.03). Comparison between group 1 and group 2 did not reveal significant difference (54.7±20.3% versus 43.3±24.6%; P=0.19). CONCLUSIONS In our large animal experimental model, simultaneous reperfusion and mechanical LV unloading yielded the smallest infarct size compared with no LV unloading or LV unloading with delayed reperfusion. In the context of prior studies showing benefit to unloading before reperfusion, these findings raise questions about how this strategy may be translated to humans.
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Affiliation(s)
- Byungsoo Ko
- Division of Cardiovascular Medicine and Nora Eccles Harrison Cardiovascular Research and Training Institute (CVRTI), Salt Lake City, Utah (B.K., S.G.D., H.I., A.T., M.B., I.T., F.G.P.W.)
- HaysMed, The University of Kansas Health System (B.K.)
| | - Stavros G Drakos
- Division of Cardiovascular Medicine and Nora Eccles Harrison Cardiovascular Research and Training Institute (CVRTI), Salt Lake City, Utah (B.K., S.G.D., H.I., A.T., M.B., I.T., F.G.P.W.)
| | - Homam Ibrahim
- Division of Cardiovascular Medicine and Nora Eccles Harrison Cardiovascular Research and Training Institute (CVRTI), Salt Lake City, Utah (B.K., S.G.D., H.I., A.T., M.B., I.T., F.G.P.W.)
- Division of Cardiology, New York University Langone Health (H.I.)
| | - Tae Soo Kang
- Division of Cardiovascular Medicine, Department of Internal Medicine, Dankook University Hospital, Cheonan, Korea (T.S.K.)
| | - Aspasia Thodou
- Division of Cardiovascular Medicine and Nora Eccles Harrison Cardiovascular Research and Training Institute (CVRTI), Salt Lake City, Utah (B.K., S.G.D., H.I., A.T., M.B., I.T., F.G.P.W.)
| | - Michael Bonios
- Division of Cardiovascular Medicine and Nora Eccles Harrison Cardiovascular Research and Training Institute (CVRTI), Salt Lake City, Utah (B.K., S.G.D., H.I., A.T., M.B., I.T., F.G.P.W.)
- Onassis Cardiac Surgery Center, Heart Failure and Transplant Program, Athens, Greece (M.B.)
| | - Iosif Taleb
- Division of Cardiovascular Medicine and Nora Eccles Harrison Cardiovascular Research and Training Institute (CVRTI), Salt Lake City, Utah (B.K., S.G.D., H.I., A.T., M.B., I.T., F.G.P.W.)
| | - Frederick Gp Welt
- Division of Cardiovascular Medicine and Nora Eccles Harrison Cardiovascular Research and Training Institute (CVRTI), Salt Lake City, Utah (B.K., S.G.D., H.I., A.T., M.B., I.T., F.G.P.W.)
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17
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Intermittent Occlusion of the Superior Vena Cava Reduces Cardiac Filling Pressures in Preclinical Models of Heart Failure. J Cardiovasc Transl Res 2019; 13:151-157. [PMID: 31773461 DOI: 10.1007/s12265-019-09916-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 09/11/2019] [Indexed: 10/25/2022]
Abstract
Congestion is a major determinant of clinical outcomes in heart failure (HF). We compared the acute hemodynamic effects of occlusion of the superior (SVC) versus the inferior vena cava (IVC) and tested a novel SVC occlusion system in swine models of HF. IVC occlusion acutely reduced left ventricular (LV) systolic and diastolic pressures, LV volumes, cardiac output (CO), and mean arterial pressure (MAP). SVC occlusion reduced LV diastolic pressure and volumes without affecting CO or MAP. The preCARDIA system is a balloon occlusion catheter and pump console which enables controlled delivery and removal of fluid into the occlusion balloon. At 6, 12, and 18 h, SVC therapy with the system provided a sustained reduction in cardiac filling pressures with stable CO and MAP. Intermittent SVC occlusion is a novel approach to reduce biventricular filling pressures in HF. The VENUS-HF trial will test the safety and feasibility of SVC therapy in HF.
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18
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Abawi D, Faragli A, Schwarzl M, Manninger M, Zweiker D, Kresoja KP, Verderber J, Zirngast B, Maechler H, Steendijk P, Pieske B, Post H, Alogna A. Cardiac power output accurately reflects external cardiac work over a wide range of inotropic states in pigs. BMC Cardiovasc Disord 2019; 19:217. [PMID: 31615415 PMCID: PMC6792198 DOI: 10.1186/s12872-019-1212-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 09/26/2019] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Cardiac power output (CPO), derived from the product of cardiac output and mean aortic pressure, is an important yet underexploited parameter for hemodynamic monitoring of critically ill patients in the intensive-care unit (ICU). The conductance catheter-derived pressure-volume loop area reflects left ventricular stroke work (LV SW). Dividing LV SW by time, a measure of LV SW min- 1 is obtained sharing the same unit as CPO (W). We aimed to validate CPO as a marker of LV SW min- 1 under various inotropic states. METHODS We retrospectively analysed data obtained from experimental studies of the hemodynamic impact of mild hypothermia and hyperthermia on acute heart failure. Fifty-nine anaesthetized and mechanically ventilated closed-chest Landrace pigs (68 ± 1 kg) were instrumented with Swan-Ganz and LV pressure-volume catheters. Data were obtained at body temperatures of 33.0 °C, 38.0 °C and 40.5 °C; before and after: resuscitation, myocardial infarction, endotoxemia, sevoflurane-induced myocardial depression and beta-adrenergic stimulation. We plotted LVSW min- 1 against CPO by linear regression analysis, as well as against the following classical indices of LV function and work: LV ejection fraction (LV EF), rate-pressure product (RPP), triple product (TP), LV maximum pressure (LVPmax) and maximal rate of rise of LVP (LV dP/dtmax). RESULTS CPO showed the best correlation with LV SW min- 1 (r2 = 0.89; p < 0.05) while LV EF did not correlate at all (r2 = 0.01; p = 0.259). Further parameters correlated moderately with LV SW min- 1 (LVPmax r2 = 0.47, RPP r2 = 0.67; and TP r2 = 0.54). LV dP/dtmax correlated worst with LV SW min- 1 (r2 = 0.28). CONCLUSION CPO reflects external cardiac work over a wide range of inotropic states. These data further support the use of CPO to monitor inotropic interventions in the ICU.
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Affiliation(s)
- Dawud Abawi
- Department of Internal Medicine and Cardiology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburgerplatz 1, 13353, Berlin, Germany
| | - Alessandro Faragli
- Department of Internal Medicine and Cardiology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburgerplatz 1, 13353, Berlin, Germany.,Berlin Institute of Health (BIH), Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany
| | - Michael Schwarzl
- Department of General and Interventional Cardiology, University Heart Center Hamburg-Eppendorf Martinistr 52, 20246, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Martin Manninger
- Department of Internal Medicine, Division of Cardiology, Medical University of Graz , Auenbruggerplatz 15, 8036 Graz, Austria
| | - David Zweiker
- Department of Internal Medicine, Division of Cardiology, Medical University of Graz , Auenbruggerplatz 15, 8036 Graz, Austria
| | - Karl-Patrik Kresoja
- Department of Cardiology, Heart Center Leipzig at University of Leipzig, Leipzig, Germany.,Leipzig Heart Institute at Heart Center Leipzig, Leipzig, Germany
| | - Jochen Verderber
- Department of Internal Medicine, Division of Cardiology, Medical University of Graz , Auenbruggerplatz 15, 8036 Graz, Austria
| | - Birgit Zirngast
- Department of Cardiothoracic Surgery, Medical University of Graz Auenbruggerplatz 29, 8036 Graz, Graz, Austria
| | - Heinrich Maechler
- Department of Cardiothoracic Surgery, Medical University of Graz Auenbruggerplatz 29, 8036 Graz, Graz, Austria
| | - Paul Steendijk
- Department of Cardiology, Leiden University Medical Center, PO 9600, 2300 RC, Leiden, The Netherlands
| | - Burkert Pieske
- Department of Internal Medicine and Cardiology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburgerplatz 1, 13353, Berlin, Germany.,Berlin Institute of Health (BIH), Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany.,Department of Internal Medicine and Cardiology, German Heart Center Berlin, Berlin, Germany
| | - Heiner Post
- Department of Internal Medicine and Cardiology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburgerplatz 1, 13353, Berlin, Germany.,Berlin Institute of Health (BIH), Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany.,Department of Cardiology, Contilia Heart and Vessel Centre, St. Marien-Hospital Mülheim, 45468, Mülheim, Germany
| | - Alessio Alogna
- Department of Internal Medicine and Cardiology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburgerplatz 1, 13353, Berlin, Germany. .,Berlin Institute of Health (BIH), Berlin, Germany. .,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany.
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Kapur NK, Karas RH, Newman S, Jorde L, Chabrashvili T, Annamalai S, Esposito M, Kimmelstiel CD, Lenihan T, Burkhoff D. First-in-human experience with occlusion of the superior vena cava to reduce cardiac filling pressures in congestive heart failure. Catheter Cardiovasc Interv 2019; 93:1205-1210. [PMID: 31112633 DOI: 10.1002/ccd.28326] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 04/21/2019] [Indexed: 12/18/2022]
Abstract
BACKGROUND Acutely decompensated heart failure remains a major clinical problem. Volume overload promotes cardiac and renal dysfunction and is associated with increased morbidity and mortality in heart failure. We hypothesized that transient occlusion of the superior vena cava (SVC) will reduce cardiac filling pressures without reducing cardiac output or systemic blood pressure. The objective of this proof of concept study was to provide initial evidence of safety and feasibility of transient SVC occlusion in patients with acutely decompensated heart failure and reduced ejection fraction. METHODS AND RESULTS In eight patients with systolic heart failure, SVC occlusion was performed using a commercially available occlusion balloon. Five minutes of SVC occlusion reduced biventricular filling pressures without decreasing systemic blood pressure or total cardiac output. In three of the eight patients, a second 10-minutes occlusion had similar hemodynamic effects. SVC occlusion was well-tolerated without development of new symptoms, new neurologic deficits, or any adverse events including stroke, heart attack, or reported SVC injury or thrombosis at 7 days of follow up. CONCLUSION We report the first clinical experience with transient SVC occlusion as a potentially new therapeutic approach to rapidly reduce cardiac filling pressures in heart failure. No prohibitive safety signal was identified and further testing to establish the clinical utility of transient SVC occlusion for acute decompensated heart failure is justified.
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Affiliation(s)
- Navin K Kapur
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
| | - Richard H Karas
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
| | - Sarah Newman
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
| | - Lena Jorde
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
| | - Tina Chabrashvili
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
| | - Shiva Annamalai
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
| | - Michele Esposito
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
| | - Carey D Kimmelstiel
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
| | - Tim Lenihan
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
| | - Daniel Burkhoff
- Molecular Cardiology Research Institute and The CardioVascular Center, Tufts Medical Center, Boston, Massachusetts
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20
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Chowdhury SM, Butts RJ, Taylor CL, Bandisode VM, Chessa KS, Hlavacek AM, Nutting A, Shirali GS, Baker GH. Longitudinal measures of deformation are associated with a composite measure of contractility derived from pressure-volume loop analysis in children. Eur Heart J Cardiovasc Imaging 2018; 19:562-568. [PMID: 29053805 PMCID: PMC5909637 DOI: 10.1093/ehjci/jex167] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 06/02/2017] [Accepted: 06/05/2017] [Indexed: 11/13/2022] Open
Abstract
Aims The relationship between echocardiographic measures of left ventricular (LV) systolic function and reference-standard measures have not been assessed in children. The objective of this study was to assess the validity of echocardiographic indices of LV systolic function via direct comparison to a novel composite measure of contractility derived from pressure-volume loop (PVL) analysis. Methods and results Children with normal loading conditions undergoing routine left heart catheterization were prospectively enrolled. PVLs were obtained via conductance catheters. A composite invasive composite contractility index (ICCI) was developed using data reduction strategies to combine four measures of contractility derived from PVL analysis. Echocardiograms were performed immediately after PVL analysis under the same anesthetic conditions. Conventional and speckle-tracking echocardiographic measures of systolic function were measured. Of 24 patients, 18 patients were heart transplant recipients, 6 patients had a small patent ductus arteriosus or small coronary fistula. Mean age was 9.1 ± 5.6 years. Upon multivariable regression, longitudinal strain was associated with ICCI (β = -0.54, P = 0.02) while controlling for indices of preload, afterload, heart rate, and LV mass under baseline conditions. Ejection fraction and shortening fraction were associated with LV mass and load indices, but not contractility. Conclusion Speckle-tracking derived longitudinal strain is associated ICCI in children with normal loading conditions. Longitudinal measures of deformation appear to accurately assess LV contractility in children.
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Affiliation(s)
- Shahryar M Chowdhury
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC, 29425, USA
| | - Ryan J Butts
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC, 29425, USA
| | - Carolyn L Taylor
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC, 29425, USA
| | - Varsha M Bandisode
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC, 29425, USA
| | - Karen S Chessa
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC, 29425, USA
| | - Anthony M Hlavacek
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC, 29425, USA
| | - Arni Nutting
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC, 29425, USA
| | - Girish S Shirali
- The Ward Family Heart Center, Children’s Mercy Hospital, 2401 Gillham Road, Kansas City, MO, 64108, USA
| | - G Hamilton Baker
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC, 29425, USA
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21
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Clinical Applications of Patient-Specific Models: The Case for a Simple Approach. J Cardiovasc Transl Res 2018; 11:71-79. [PMID: 29453747 DOI: 10.1007/s12265-018-9787-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 01/05/2018] [Indexed: 01/08/2023]
Abstract
Over the past several decades, increasingly sophisticated models of the heart have provided important insights into cardiac physiology and are increasingly used to predict the impact of diseases and therapies on the heart. In an era of personalized medicine, many envision patient-specific computational models as a powerful tool for personalizing therapy. Yet the complexity of current models poses important challenges, including identifying model parameters and completing calculations quickly enough for routine clinical use. We propose that early clinical successes are likely to arise from an alternative approach: relatively simple, fast, phenomenologic models with a small number of parameters that can be easily (and automatically) customized. We discuss examples of simple yet foundational models that have already made a tremendous impact on clinical education and practice, and make the case that reducing rather than increasing model complexity may be the key to realizing the promise of patient-specific modeling for clinical applications.
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22
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Schroeder LW, Chowdhury SM, Burnette AL, Kavarana MN, Baker GH, Savage AJ, Atz AM, Butts RJ. Longer Ischemic Time is Associated with Increased Ventricular Stiffness as Measured by Pressure-Volume Loop Analysis in Pediatric Heart Transplant Recipients. Pediatr Cardiol 2018; 39:324-328. [PMID: 29090350 PMCID: PMC5799027 DOI: 10.1007/s00246-017-1758-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 10/24/2017] [Indexed: 01/20/2023]
Abstract
BACKGROUND The purpose of this study was to investigate the associations between clinical factors and cardiac function as measured by pressure-volume loops (PVLs) in a pediatric heart transplant cohort. METHODS Patients (age < 20 years) who underwent heart transplantation presenting for a clinically indicated catheterization were enrolled. PVLs were recorded using microconductance catheters (CD Leycom®, Zoetermeer, Netherlands). Demographic data, serum B-type natriuretic peptide (BNP), time from transplant, ischemic time, presence of transplant coronary artery disease, donor-specific antibodies, and history of rejection were recorded at the time of catheterization. PVL data included contractility indices: end-systolic elastance and preload recruitable stroke work; ventricular-arterial coupling index; ventricular stiffness constant, Beta; and isovolumic relaxation time constant, tau. Associations between PVL measures and clinical data were investigated using non-parametric statistical tests. RESULTS A total of 18 patients were enrolled. Median age was 8.7 years (IQR 5-14 years). There were ten males and eight females. Six patients had a history of rejection and ten had positive donor-specific antibodies. There was no transplant coronary artery disease. Median BNP was 100 pg/mL (IQR 46-140). Time from transplant to PVL obtained during catheterization procedure was 4.1 years (IQR 1.7-7.8 year). No single clinical characteristic was statistically significant when correlated with PVL data. However, longer ischemic time was associated with worse Beta (r = 0.49, p = 0.05). CONCLUSIONS Our study found that longer ischemic times are associated with increased left ventricular stiffness. No other single clinical variable is associated with cardiac dysfunction as determined by PVL analysis.
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Affiliation(s)
- Luke W. Schroeder
- Division of Cardiology, Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC 29425, USA
| | - Shahryar M. Chowdhury
- Division of Cardiology, Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC 29425, USA
| | - Ali L. Burnette
- Division of Cardiology, Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC 29425, USA
| | - Minoo N. Kavarana
- Division of Cardiothoracic Surgery, Department of Surgery, Medical University of South Carolina, Charleston, SC 29425, USA
| | - G. Hamilton Baker
- Division of Cardiology, Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC 29425, USA
| | - Andrew J. Savage
- Division of Cardiology, Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC 29425, USA
| | - Andrew M. Atz
- Division of Cardiology, Department of Pediatrics, Medical University of South Carolina, 165 Ashley Ave, MSC 915, Charleston, SC 29425, USA
| | - Ryan J. Butts
- Division of Cardiology, Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, USA
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23
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Bridging the gap between measurements and modelling: a cardiovascular functional avatar. Sci Rep 2017; 7:6214. [PMID: 28740184 PMCID: PMC5524911 DOI: 10.1038/s41598-017-06339-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 06/12/2017] [Indexed: 11/08/2022] Open
Abstract
Lumped parameter models of the cardiovascular system have the potential to assist researchers and clinicians to better understand cardiovascular function. The value of such models increases when they are subject specific. However, most approaches to personalize lumped parameter models have thus far required invasive measurements or fall short of being subject specific due to a lack of the necessary clinical data. Here, we propose an approach to personalize parameters in a model of the heart and the systemic circulation using exclusively non-invasive measurements. The personalized model is created using flow data from four-dimensional magnetic resonance imaging and cuff pressure measurements in the brachial artery. We term this personalized model the cardiovascular avatar. In our proof-of-concept study, we evaluated the capability of the avatar to reproduce pressures and flows in a group of eight healthy subjects. Both quantitatively and qualitatively, the model-based results agreed well with the pressure and flow measurements obtained in vivo for each subject. This non-invasive and personalized approach can synthesize medical data into clinically relevant indicators of cardiovascular function, and estimate hemodynamic variables that cannot be assessed directly from clinical measurements.
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24
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Chowdhury SM, Butts RJ, Taylor CL, Bandisode VM, Chessa KS, Hlavacek AM, Shirali GS, Baker GH. Validation of Noninvasive Measures of Left Ventricular Mechanics in Children: A Simultaneous Echocardiographic and Conductance Catheterization Study. J Am Soc Echocardiogr 2016; 29:640-7. [PMID: 27025669 DOI: 10.1016/j.echo.2016.02.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Indexed: 10/22/2022]
Abstract
BACKGROUND The accuracy of echocardiography in evaluating left ventricular contractility has not been validated in children. The objective of this study was to compare echocardiographic measures of contractility with those derived from pressure-volume loop (PVL) analysis in children. METHODS Patients with relatively normal loading conditions undergoing routine left heart catheterization were prospectively enrolled. PVLs were obtained via conductance catheters. The gold-standard measure of contractility, end-systolic elastance (Ees), was obtained via balloon occlusion of one or both vena cavae. Echocardiograms were performed immediately after PVL analysis under the same anesthetic conditions. Single-beat estimations of echocardiographic Ees were calculated using four different methods. These estimates were calculated using a combination of noninvasive blood pressure readings, ventricular volumes derived from three-dimensional echocardiography, and Doppler time intervals. RESULTS Of 24 patients, 18 patients were heart transplant recipients, and six patients had small patent ductus arteriosus or small coronary fistulae. The mean age was 9.1 ± 5.6 years. The average invasive Ees was 3.04 ± 1.65 mm Hg/mL. Invasive Ees correlated best with echocardiographic Ees by the method of Tanoue (r = 0.85, P < .01), with a mean difference of -0.07 mm Hg/mL (95% limits of agreement, -2.0 to 1.4 mm Hg/mL). CONCLUSIONS Echocardiographic estimates of Ees correlate well with gold-standard measures obtained via conductance catheters in children with relatively normal loading conditions. The use of these noninvasive measures in accurately assessing left ventricular contractility appears promising and merits further study in children.
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Affiliation(s)
- Shahryar M Chowdhury
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina.
| | - Ryan J Butts
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina
| | - Carolyn L Taylor
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina
| | - Varsha M Bandisode
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina
| | - Karen S Chessa
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina
| | - Anthony M Hlavacek
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina
| | - Girish S Shirali
- The Ward Family Heart Center, Children's Mercy Hospital, Kansas City, Missouri
| | - G Hamilton Baker
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina
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Axell RG, Hoole SP, Hampton-Till J, White PA. RV diastolic dysfunction: time to re-evaluate its importance in heart failure. Heart Fail Rev 2015; 20:363-73. [PMID: 25633340 DOI: 10.1007/s10741-015-9472-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Right ventricular (RV) diastolic dysfunction was first reported as an indicator for the assessment of ventricular dysfunction in heart failure a little over two decades ago. However, the underlying mechanisms and precise role of RV diastolic dysfunction in heart failure remain poorly described. Complexities in the structure and function of the RV make the detailed assessment of the contractile performance challenging when compared to its left ventricular (LV) counterpart. LV dysfunction is known to directly affect patient outcome in heart failure. As such, the focus has therefore been on LV function. Nevertheless, a strategy for the diagnosis and assessment of RV diastolic dysfunction has not been established. Here, we review the different causal mechanisms underlying RV diastolic dysfunction, summarising the current assessment techniques used in a clinical environment. Finally, we explore the role of load-independent indices of RV contractility, derived from the conductance technique, to fully interrogate the RV and expand our knowledge and understanding of RV diastolic dysfunction. Accurate assessment of RV contractility may yield further important prognostic information that will benefit patients with diastolic heart failure.
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Affiliation(s)
- Richard G Axell
- Medical Physics and Clinical Engineering, Addenbrookes Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0QQ, UK,
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Mynard JP, Smolich JJ. One-Dimensional Haemodynamic Modeling and Wave Dynamics in the Entire Adult Circulation. Ann Biomed Eng 2015; 43:1443-60. [DOI: 10.1007/s10439-015-1313-8] [Citation(s) in RCA: 136] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 03/24/2015] [Indexed: 01/09/2023]
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27
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Assessment of Ventricular Function Using the Pressure-Volume Relationship. CONGENIT HEART DIS 2015. [DOI: 10.1007/978-4-431-54355-8_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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28
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Tan W, Madhavan K, Hunter KS, Park D, Stenmark KR. Vascular stiffening in pulmonary hypertension: cause or consequence? (2013 Grover Conference series). Pulm Circ 2014; 4:560-80. [PMID: 25610594 PMCID: PMC4278618 DOI: 10.1086/677370] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 05/27/2014] [Indexed: 12/24/2022] Open
Abstract
Recent studies have indicated that systemic arterial stiffening is a precursor to hypertension and that hypertension, in turn, can perpetuate arterial stiffening. Pulmonary artery (PA) stiffening is also well documented to occur in pulmonary hypertension (PH), and there is evidence that pulmonary vascular stiffness (PVS) may be a better predictor of outcome than pulmonary vascular resistance (PVR). We have hypothesized that the decreased flow-damping function of elastic PAs in PH likely initiates and/or perpetuates dysfunction of pulmonary microvasculature. Recent studies have shown that large-vessel stiffening increases flow pulsatility in the distal pulmonary vasculature, leading to endothelial dysfunction within a proinflammatory, vasoconstricting, and profibrogenic environment. The intricate role of stiffening-stimulated high pulsatile flow in endothelial cell dysfunction includes stepwise molecular events underlying PA hypertrophy, inflammation, endothelial-mesenchymal transition, and fibrosis. In addition to contributing to microenvironmental alterations of the distal vasculature, disordered proximal-distal PA coupling likely also plays a role in increasing ventricular afterload, ultimately causing right ventricle (RV) dysfunction and death. Current therapeutic treatments do not provide a realistic approach to destiffening arteries and, thus, to potentially abrogating the effects of high pulsatile flow on the distal pulmonary vasculature or the increased work imposed by stiffening on the RV. Scrutinizing the effect of PA stiffening on high pulsatile flow-induced cellular and molecular changes, and vice versa, might lead to important new therapeutic options that abrogate PA remodeling and PH development. With a clear understanding that PA stiffening may contribute to the progression of PH to an irreversible state by contributing to chronic microvascular damage in lungs, future studies should be aimed first at defining the underlying mechanisms leading to PA stiffening and then at improved treatment approaches based on these findings.
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Affiliation(s)
- Wei Tan
- Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, USA
- Cardiovascular Pulmonary Research Laboratories, University of Colorado Denver, Aurora, Colorado, USA
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder, Colorado, USA
| | - Krishna Madhavan
- Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, USA
- Department of Bioengineering, University of Colorado Denver, Aurora, Colorado, USA
| | - Kendall S. Hunter
- Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, USA
- Department of Bioengineering, University of Colorado Denver, Aurora, Colorado, USA
| | - Daewon Park
- Department of Bioengineering, University of Colorado Denver, Aurora, Colorado, USA
| | - Kurt R. Stenmark
- Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, USA
- Cardiovascular Pulmonary Research Laboratories, University of Colorado Denver, Aurora, Colorado, USA
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Mariani JA, Smolic A, Preovolos A, Byrne MJ, Power JM, Kaye DM. Augmentation of left ventricular mechanics by recirculation-mediated AAV2/1-SERCA2a gene delivery in experimental heart failure. Eur J Heart Fail 2014; 13:247-53. [DOI: 10.1093/eurjhf/hfq234] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Justin A. Mariani
- Heart Failure Research Group, Baker IDI Heart and Diabetes Institute; PO Box 6492 St Kilda Rd Central Melbourne VIC 8008 Australia
| | - Anka Smolic
- Heart Failure Research Group, Baker IDI Heart and Diabetes Institute; PO Box 6492 St Kilda Rd Central Melbourne VIC 8008 Australia
| | - Arthur Preovolos
- Heart Failure Research Group, Baker IDI Heart and Diabetes Institute; PO Box 6492 St Kilda Rd Central Melbourne VIC 8008 Australia
| | - Melissa J. Byrne
- Heart Failure Research Group, Baker IDI Heart and Diabetes Institute; PO Box 6492 St Kilda Rd Central Melbourne VIC 8008 Australia
| | - John M. Power
- Heart Failure Research Group, Baker IDI Heart and Diabetes Institute; PO Box 6492 St Kilda Rd Central Melbourne VIC 8008 Australia
| | - David M. Kaye
- Heart Failure Research Group, Baker IDI Heart and Diabetes Institute; PO Box 6492 St Kilda Rd Central Melbourne VIC 8008 Australia
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Tedford RJ, Mudd JO, Girgis RE, Mathai SC, Zaiman AL, Housten-Harris T, Boyce D, Kelemen BW, Bacher AC, Shah AA, Hummers LK, Wigley FM, Russell SD, Saggar R, Saggar R, Maughan WL, Hassoun PM, Kass DA. Right ventricular dysfunction in systemic sclerosis-associated pulmonary arterial hypertension. Circ Heart Fail 2013; 6:953-63. [PMID: 23797369 DOI: 10.1161/circheartfailure.112.000008] [Citation(s) in RCA: 181] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND Systemic sclerosis–associated pulmonary artery hypertension (SScPAH) has a worse prognosis compared with idiopathic pulmonary arterial hypertension (IPAH), with a median survival of 3 years after diagnosis often caused by right ventricular (RV) failure. We tested whether SScPAH or systemic sclerosis–related pulmonary hypertension with interstitial lung disease imposes a greater pulmonary vascular load than IPAH and leads to worse RV contractile function. METHODS AND RESULTS We analyzed pulmonary artery pressures and mean flow in 282 patients with pulmonary hypertension (166 SScPAH, 49 systemic sclerosis–related pulmonary hypertension with interstitial lung disease, and 67 IPAH). An inverse relation between pulmonary resistance and compliance was similar for all 3 groups, with a near constant resistance×compliance product. RV pressure–volume loops were measured in a subset, IPAH (n=5) and SScPAH (n=7), as well as SSc without PH (n=7) to derive contractile indexes (end-systolic elastance [Ees] and preload recruitable stroke work [Msw]), measures of RV load (arterial elastance [Ea]), and RV pulmonary artery coupling (Ees/Ea). RV afterload was similar in SScPAH and IPAH (pulmonary vascular resistance=7.0±4.5 versus 7.9±4.3 Wood units; Ea=0.9±0.4 versus 1.2±0.5 mm Hg/mL; pulmonary arterial compliance=2.4±1.5 versus 1.7±1.1 mL/mm Hg; P>0.3 for each). Although SScPAH did not have greater vascular stiffening compared with IPAH, RV contractility was more depressed (Ees=0.8±0.3 versus 2.3±1.1, P<0.01; Msw=21±11 versus 45±16, P=0.01), with differential RV-PA uncoupling (Ees/Ea=1.0±0.5 versus 2.1±1.0; P=0.03). This ratio was higher in SSc without PH (Ees/Ea=2.3±1.2; P=0.02 versus SScPAH). CONCLUSIONS RV dysfunction is worse in SScPAH compared with IPAH at similar afterload, and may be because of intrinsic systolic function rather than enhanced pulmonary vascular resistive and pulsatile loading.
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MESH Headings
- Adult
- Aged
- Analysis of Variance
- Arterial Pressure
- Cardiac Catheterization
- Chi-Square Distribution
- Compliance
- Familial Primary Pulmonary Hypertension
- Female
- Humans
- Hypertension, Pulmonary/diagnosis
- Hypertension, Pulmonary/etiology
- Hypertension, Pulmonary/physiopathology
- Linear Models
- Lung Diseases, Interstitial/etiology
- Lung Diseases, Interstitial/physiopathology
- Male
- Middle Aged
- Myocardial Contraction
- Nonlinear Dynamics
- Predictive Value of Tests
- Prognosis
- Pulmonary Artery/physiopathology
- Pulmonary Circulation
- Risk Factors
- Scleroderma, Systemic/complications
- United States
- Vascular Resistance
- Ventricular Dysfunction, Right/diagnosis
- Ventricular Dysfunction, Right/etiology
- Ventricular Dysfunction, Right/physiopathology
- Ventricular Function, Right
- Ventricular Pressure
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Yotti R, Bermejo J, Benito Y, Sanz-Ruiz R, Ripoll C, Martínez-Legazpi P, del Villar CP, Elízaga J, González-Mansilla A, Barrio A, Bañares R, Fernández-Avilés F. Validation of noninvasive indices of global systolic function in patients with normal and abnormal loading conditions: a simultaneous echocardiography pressure-volume catheterization study. Circ Cardiovasc Imaging 2013; 7:164-72. [PMID: 24173273 DOI: 10.1161/circimaging.113.000722] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Noninvasive indices based on Doppler echocardiography are increasingly used in clinical cardiovascular research to evaluate left ventricular global systolic chamber function. Our objectives were to clinically validate ultrasound-based methods of global systolic chamber function to account for differences between patients in conditions of abnormal load, and to assess their sensitivity to load confounders. METHODS AND RESULTS Twenty-seven patients (8 dilated cardiomyopathy, 10 normal ejection fraction, and 9 end-stage liver disease) underwent simultaneous echocardiography and left heart catheterization with pressure-conductance instrumentation. The reference index, maximal elastance (Emax), was calculated from pressure-volume loop data obtained during acute inferior vena cava occlusion. A wide range of values were observed for left ventricular systolic chamber function (Emax: 2.8±1.0 mm Hg/mL), preload, and afterload. Among the noninvasive indices tested, the peak ejection intraventricular pressure difference showed the best correlation with Emax (R=0.75). A significant but weaker correlation with Emax was observed for ejection fraction (R=0.41), midwall fractional shortening (R=0.51), global circumferential strain (R=-0.53), and strain rate (R=-0.46). Longitudinal strain and strain rate failed to correlate with Emax, as did noninvasive single-beat estimations of this index. Principal component and multiple regression analyses demonstrated that peak ejection intraventricular pressure difference was less sensitive to load, whereas ejection fraction and longitudinal strain and strain rate were heavily influenced by afterload. CONCLUSIONS Current ultrasound methods have limited accuracy to characterize global left ventricular systolic chamber function in a given patient. The Doppler-derived peak ejection intraventricular pressure difference should be preferred for this purpose because it best correlates with the reference index and is more robust in conditions of abnormal load.
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Choi HW, Jansen B, Birrer D, Kassab GS. Effect of saline injection mixing on accuracy of conductance lumen sizing of peripheral vessels. PLoS One 2013; 8:e74622. [PMID: 24058606 PMCID: PMC3772889 DOI: 10.1371/journal.pone.0074622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 08/05/2013] [Indexed: 12/03/2022] Open
Abstract
Transient displacement of blood in vessel lumen with saline injection is necessary in the conductance method for measurement of arterial cross-sectional area (CSA). The displacement of blood is dictated by the interactions between arterial flow hemodynamics and saline injection dynamics. The objective of the present study is to understand how the accuracy of conductance measurements is affected by the saline injection. Computational simulations were performed to assess the error in predictions of arterial CSA using conductance measurements over a range of peripheral artery diameters (i.e., 4, 7, and 10 mm) with an introducing catheter (6 Fr.) for various blood flow and saline injection rates. The simulation results were validated using the conductance measurements of the phantoms with known diameters (i.e., 7 and 10 mm). The results demonstrated that a minimum ratio of saline injection rate to blood flow rate of 3 is needed to fully displace the blood and result in accurate measurement of CSA for the peripheral artery sizes considered. Furthermore, the error was shown to be minimized as the detection electrodes are positioned between the distal to the mixing zone induced by saline injection and far downstream (4–8 cm from the injection catheter tip). The present study shows that even for the large peripheral arteries (7–10 mm) where mixing can occur, an appropriate injection rate and detection position can produce accurate measurement of lumen size.
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Affiliation(s)
- Hyo Won Choi
- Department of Biomedical Engineering, Indiana University Purdue University, Indianapolis, Indiana, United States of America
| | - Benjamin Jansen
- Department of Biomedical Engineering, Indiana University Purdue University, Indianapolis, Indiana, United States of America
| | - David Birrer
- Department of Biomedical Engineering, Indiana University Purdue University, Indianapolis, Indiana, United States of America
| | - Ghassan S. Kassab
- Department of Biomedical Engineering, Indiana University Purdue University, Indianapolis, Indiana, United States of America
- Department of Surgery, Indiana University Purdue University, Indianapolis, Indiana, United States of America
- Department of Cellular and Integrative Physiology, Indiana University Purdue University, Indianapolis, Indiana, United States of America
- * E-mail:
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Dini FL, Guarini G, Ballo P, Carluccio E, Maiello M, Capozza P, Innelli P, Rosa GM, Palmiero P, Galderisi M, Razzolini R, Nodari S. The left ventricle as a mechanical engine. J Cardiovasc Med (Hagerstown) 2013; 14:214-20. [DOI: 10.2459/jcm.0b013e32834ae7fe] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Choi HW, Zhang ZD, Farren ND, Kassab GS. Implications of complex anatomical junctions on conductance catheter measurements of coronary arteries. J Appl Physiol (1985) 2013; 114:656-64. [PMID: 23305988 DOI: 10.1152/japplphysiol.00987.2012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In vivo, the position of the conductance catheter to measure vessel lumen cross-sectional area may vary depending on where the conductance catheter is deployed in the complex anatomical geometry of arteries, including branches, bifurcations, or curvatures. The objective here is to determine how such geometric variations affect the cross-sectional area (CSA) estimates obtained using the cylindrical model. Computer simulations and in vitro and in vivo experiments were used to assess how the electric field and associated CSA measurement accuracy are affected by three typical in vivo conditions: 1) a vessel with abrupt change in lumen diameter (e.g., transition from aorta to coronary ostia); 2) a vessel with a T-bifurcation or a Y-bifurcation; and 3) a vessel curvature, such as in the right coronary artery, aorta, or pulmonary artery. The error in diameter from simulation results was shown to be relatively small (<7%), unless the detection electrodes were placed near the junction between two different lumen diameters or at a bifurcation junction. Furthermore, the present findings show that the effect of misaligned catheter-vessel geometrical configuration and vessel curvature on measurement accuracy is negligible. Collectively, the findings support the accuracy of the conductance method for sizing blood vessels, despite the geometric complexities of the cardiovascular system, as long as the detection electrodes are not placed at a large discontinuity in diameter or at bifurcation junctions.
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Affiliation(s)
- Hyo Won Choi
- Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, USA
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Won Choi H, Jansen B, Zhang ZD, Kassab GS. Impact of surrounding tissue on conductance measurement of coronary and peripheral lumen area. J R Soc Interface 2012; 9:2971-82. [PMID: 22718991 PMCID: PMC3479898 DOI: 10.1098/rsif.2012.0188] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 05/23/2012] [Indexed: 11/12/2022] Open
Abstract
Parallel conductance (electric current flow through surrounding tissue) is an important determinant of accurate measurements of arterial lumen diameter, using the conductance method. The present study is focused on the role of non-uniform geometrical/electrical configurations of surrounding tissue, which are a primary source of electric current leakage. Computational models were constructed to simulate the conductance catheter measurement with two different excitation electrodes spacings (i.e. 12 and 20 mm for coronary and peripheral sizing, respectively) for different vessel-tissue configurations: (i) blood vessel fully embedded in muscle tissue, (ii) blood vessel superficially embedded in muscle tissue, and (iii) blood vessel superficially embedded in muscle tissue with fat covering half of the arterial vessel (anterior portion). The simulations suggest that the parallel conductance and accuracy of measurement is dependent on the inhomogeneous/anisotropic configuration of surrounding tissue, including the asymmetric dimension and anisotropy in electrical conductivity of surrounding tissue. Specifically, the measurement was shown to be accurate as long as the vessel was superficial, regardless of the considerable total surrounding tissue dimension for coronary or peripheral arteries. Moreover, it was shown that the unfavourable impact of parallel conductance on the accuracy of conductance catheter measurement is decreased by the combination of a lower transverse electrical conductivity of surrounding muscle tissue, a smaller electrode spacing and a larger lumen diameter. The present findings confirm that the conductance catheter technique provides an accurate platform for sizing of clinically relevant (i.e. superficial and diseased) arteries.
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Affiliation(s)
- Hyo Won Choi
- Department of Biomedical Engineering, Indiana University Purdue University, Indianapolis, IN, USA
| | - Benjamin Jansen
- Department of Biomedical Engineering, Indiana University Purdue University, Indianapolis, IN, USA
| | - Zhen-Du Zhang
- Department of Biomedical Engineering, Indiana University Purdue University, Indianapolis, IN, USA
| | - Ghassan S. Kassab
- Department of Biomedical Engineering, Indiana University Purdue University, Indianapolis, IN, USA
- Department of Surgery, Indiana University Purdue University, Indianapolis, IN, USA
- Department of Cellular and Integrative Physiology, Indiana University Purdue University, Indianapolis, IN, USA
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36
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Detombe SA, Xiang FL, Dunmore-Buyze J, White JA, Feng Q, Drangova M. Rapid microcomputed tomography suggests cardiac enlargement occurs during conductance catheter measurements in mice. J Appl Physiol (1985) 2012; 113:142-8. [PMID: 22518829 DOI: 10.1152/japplphysiol.00831.2011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Conductance catheters (CC) represent an established method of determining cardiac function in mice; however, the potentially detrimental effects a catheter may have on the mouse heart have never been evaluated. The present study takes advantage of rapid three-dimensional (3D) microcomputed tomography (CT) to compare simultaneously acquired micro-CT and CC measurements of left ventricular (LV) volumes in healthy and infarcted mice and to determine changes in LV volume and function associated with CC insertion. LV volumes were measured in C57BL/6 mice (10 healthy, 10 infarcted, 2% isoflurane anesthesia) using a 1.4-Fr Millar CC. 3D micro-CT images of each mouse were acquired before CC insertion as well as during catheterization. Each CT scan produced high-resolution images throughout the entire cardiac cycle in <1 min, enabling accurate volume measurements as well as direct visualization of the CC within the LV. Bland-Altman analysis demonstrated that CC measurements underestimate volume compared with CT measurements in both healthy [bias of -18.4 and -28.9 μl for end-systolic (ESV) and end-diastolic volume (EDV), respectively] and infarcted mice (ESV = -51.6 μl and EDV = -71.7 μl); underestimation was attributed to the off-center placement of the catheter. Individual evaluation of each heart revealed LV dilation following CC insertion in 40% of mice in each group. No change in ejection fraction was observed, suggesting the enlargement was caused by volume overload associated with disruption of the papillary muscles or chords. The enlargement witnessed was not significant; however, the results suggest the potential for CC insertion to detrimentally affect mouse myocardium, necessitating further investigation.
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Affiliation(s)
- Sarah A Detombe
- Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, Canada
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Mynard JP, Davidson MR, Penny DJ, Smolich JJ. A simple, versatile valve model for use in lumped parameter and one-dimensional cardiovascular models. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2012; 28:626-641. [PMID: 25364842 DOI: 10.1002/cnm.1466] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 07/12/2011] [Accepted: 07/13/2011] [Indexed: 06/04/2023]
Abstract
Lumped parameter and one-dimensional models of the cardiovascular system generally employ ideal cardiac and/or venous valves that open and close instantaneously. However, under normal or pathological conditions, valves can exhibit complex motions that are mainly determined by the instantaneous difference between upstream and downstream pressures. We present a simple valve model that predicts valve motion on the basis of this pressure difference, and can be used to investigate not only valve pathology, but a wide range of cardiac and vascular factors that are likely to influence valve motion.
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Affiliation(s)
- J P Mynard
- Heart Research Group, Murdoch Childrens Research Institute, Flemington Rd. Parkville, VIC, Australia; Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia.
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Choi HW, Farren ND, Zhang ZD, Huo Y, Kassab GS. Conductance catheter measurements of lumen area of stenotic coronary arteries: theory and experiment. J Appl Physiol (1985) 2011; 111:758-65. [PMID: 21680882 DOI: 10.1152/japplphysiol.00304.2011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
An injection of saline solution is required for the measurement of vessel lumen area using a conductance catheter. The injection of room temperature saline to displace blood in a vessel inevitably involves mass and heat transport and electric field conductance. The objective of the present study is to understand the accuracy of conductance method based on the phenomena associated with the saline injection into a stenotic blood vessel. Computational fluid dynamics were performed to simulate flow and its relation to transport and electric field in a stenotic artery for two different sized conductance catheters (0.9 and 0.35 mm diameter) over a range of occlusions [56–84% cross-sectional area (CSA) stenosis]. The results suggest that the performance of conductance catheter is dependent on catheter size and severity of stenosis more significantly for 0.9 mm than for 0.35 mm catheter. Specifically, the time of detection of 95% of injected saline solution at the detection electrodes was shown to range from 0.67 to 3.7 s and 0.82 to 0.94 s for 0.9 mm and 0.35 mm catheter, respectively. The results also suggest that the detection electrodes of conductance catheter should be placed outside of flow recirculation region distal to the stenosis to minimize the detection time. Finally, the simulations show that the accuracy in distal CSA measurements, however, is not significantly altered by whether the position of detection electrodes is inside or outside of recirculation zone (error was within 12% regardless of detection electrodes position). The results were experimentally validated for one lesion geometry and the simulation results are within 8% of actual measurements. The simulation of conductance catheter injection method may lead to further optimization of device and method for accurate sizing of diseased coronary arteries, which has clinical relevance to percutaneous intervention.
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Affiliation(s)
| | | | | | | | - Ghassan S. Kassab
- Departments of 1Biomedical Engineering,
- Surgery, and
- Cellular and Integrative Physiology, Indiana University Purdue University, Indianapolis, Indiana
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Angeli FS, Amabile N, Shapiro M, Mirsky R, Bartlett L, Zhang Y, Virmani R, Chatterjee K, Boyle A, Grossman W, Yeghiazarians Y. Cytokine combination therapy with erythropoietin and granulocyte colony stimulating factor in a porcine model of acute myocardial infarction. Cardiovasc Drugs Ther 2011; 24:409-20. [PMID: 20809214 PMCID: PMC3051072 DOI: 10.1007/s10557-010-6263-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Purpose Erythropoietin (EPO) and granulocyte colony stimulating factor (GCSF) have generated interest as novel therapies after myocardial infarction (MI), but the effect of combination therapy has not been studied in the large animal model. We investigated the impact of prolonged combination therapy with EPO and GCSF on cardiac function, infarct size, and vascular density after MI in a porcine model. Methods MI was induced in pigs by a 90 min balloon occlusion of the left anterior descending coronary artery. 16 animals were treated with EPO+GCSF, or saline (control group). Cardiac function was assessed by echocardiography and pressure-volume measurements at baseline, 1 and 6 weeks post-MI. Histopathology was performed 6 weeks post-MI. Results At week 6, EPO+GCSF therapy stabilized left ventricular ejection fraction, (41 ± 1% vs. 33 ± 1%, p < 0.01) and improved diastolic function compared to the control group. Histopathology revealed increased areas of viable myocardium and vascular density in the EPO+GCSF therapy, compared to the control. Despite these encouraging results, in a historical analysis comparing combination therapy with monotherapy with EPO or GCSF, there were no significant additive benefits in the LVEF and volumes overtime using the combination therapy. Conclusion Our findings indicate that EPO+GCSF combination therapy promotes stabilization of cardiac function after acute MI. However, combination therapy does not seem to be superior to monotherapy with either EPO or GCSF.
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Affiliation(s)
- Franca S. Angeli
- Division of Cardiology, Department of Medicine, University of California, 505 Parnassus Avenue, L-523, Box 0103, San Francisco, CA 94143-0103 USA
| | - Nicolas Amabile
- Division of Cardiology, Department of Medicine, University of California, 505 Parnassus Avenue, L-523, Box 0103, San Francisco, CA 94143-0103 USA
| | - Mia Shapiro
- Division of Cardiology, Department of Medicine, University of California, 505 Parnassus Avenue, L-523, Box 0103, San Francisco, CA 94143-0103 USA
| | - Rachel Mirsky
- Division of Cardiology, Department of Medicine, University of California, 505 Parnassus Avenue, L-523, Box 0103, San Francisco, CA 94143-0103 USA
| | | | - Yan Zhang
- Division of Cardiology, Department of Medicine, University of California, 505 Parnassus Avenue, L-523, Box 0103, San Francisco, CA 94143-0103 USA
| | - Renu Virmani
- CVpath Institute, 19 Firstfield Road, Gaithersburg, MD USA
| | - Kanu Chatterjee
- Division of Cardiology, Department of Medicine, University of California, 505 Parnassus Avenue, L-523, Box 0103, San Francisco, CA 94143-0103 USA
| | - Andrew Boyle
- Division of Cardiology, Department of Medicine, University of California, 505 Parnassus Avenue, L-523, Box 0103, San Francisco, CA 94143-0103 USA
| | - William Grossman
- Division of Cardiology, Department of Medicine, University of California, 505 Parnassus Avenue, L-523, Box 0103, San Francisco, CA 94143-0103 USA
| | - Yerem Yeghiazarians
- Division of Cardiology, Department of Medicine, University of California, 505 Parnassus Avenue, L-523, Box 0103, San Francisco, CA 94143-0103 USA
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40
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Chia-Ling Wei, Chung-Dann Kan, Jieh-Neng Wang, Yi-Wen Wang, Chin-Hong Chen, Mei-Ling Tsai. Does Conductance Catheter Measurement System Give Consistent and Reliable Pressure–Volume Relations in Rats? IEEE Trans Biomed Eng 2011; 58:1804-13. [DOI: 10.1109/tbme.2011.2118210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Proof for piroximone's inotropic influence: Can it safely be used in coronary artery disease? analysis of end-systolic pressure-volume relations (conductance technique). Int J Angiol 2011. [DOI: 10.1007/bf02043006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Choi JO, Lee SC, Choi SH, Kim SM, Choi JH, Park JR, Song BG, Chang SA, Park SJ, Park SW, Park PW. Noninvasive Assessment of Left Ventricular Stroke Work Index in Patients with Severe Mitral Regurgitation: Correlation with Invasive Measurement and Exercise Capacity. Echocardiography 2010; 27:1161-9. [DOI: 10.1111/j.1540-8175.2010.01222.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Mukkamala R, Xu D. Continuous and less invasive central hemodynamic monitoring by blood pressure waveform analysis. Am J Physiol Heart Circ Physiol 2010; 299:H584-99. [PMID: 20622106 PMCID: PMC2944477 DOI: 10.1152/ajpheart.00303.2010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 07/05/2010] [Indexed: 12/24/2022]
Abstract
Blood pressure waveform analysis may permit continuous (i.e., automated) and less invasive (i.e., safer and simpler) central hemodynamic monitoring in the intensive care unit and other clinical settings without requiring any instrumentation beyond what is already in use or available. This practical approach has been a topic of intense investigation for decades and may garner even more interest henceforth due to the evolving demographics as well as recent trends in clinical hemodynamic monitoring. Here, we review techniques that have appeared in the literature for mathematically estimating clinically significant central hemodynamic variables, such as cardiac output, from different blood pressure waveforms. We begin by providing the rationale for pursuing such techniques. We then summarize earlier techniques and thereafter overview recent techniques by our collaborators and us in greater depth while pinpointing both their strengths and weaknesses. We conclude with suggestions for future research directions in the field and a description of some potential clinical applications of the techniques.
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Affiliation(s)
- Ramakrishna Mukkamala
- Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824-1226, USA.
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Champion HC, Michelakis ED, Hassoun PM. Comprehensive invasive and noninvasive approach to the right ventricle-pulmonary circulation unit: state of the art and clinical and research implications. Circulation 2009; 120:992-1007. [PMID: 19752350 DOI: 10.1161/circulationaha.106.674028] [Citation(s) in RCA: 340] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Hunter C Champion
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Pittsburgh Medical Center, NW628 Montefiore Hospital, 3459 Fifth Avenue, Pittsburgh, PA 15260, USA.
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San Román JA, Candell-Riera J, Arnold R, Sánchez PL, Aguadé-Bruix S, Bermejo J, Revilla A, Villa A, Cuéllar H, Hernández C, Fernández-Avilés F. Quantitative analysis of left ventricular function as a tool in clinical research. Theoretical basis and methodology. Rev Esp Cardiol 2009; 62:535-51. [PMID: 19406068 DOI: 10.1016/s1885-5857(09)71836-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The usefulness the left ventricular ejection fraction as a surrogate endpoint in clinical trials has been confirmed by numerous studies. However, if this approach is to be applied successfully, images must be acquired in a rigorously controlled manner, and it is advisable to use measurement units that have been specifically developed for quantitative analysis of the imaging parameters obtained with current imaging techniques. This review summarizes what is now known about the left ventricular ejection fraction and left ventricular volumes, discusses the importance of measurement units in image analysis, and describes the different imaging techniques available. Finally, there is a discussion of how to select the best imaging technique for specific clinical applications.
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46
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Wei CL, Shih MH. Calibration Capacity of the Conductance-to-Volume Conversion Equations for the Mouse Conductance Catheter Measurement System. IEEE Trans Biomed Eng 2009; 56:1627-34. [DOI: 10.1109/tbme.2009.2016215] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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47
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Chen CE, Wei CL. Bandwidth measurement of the conductance catheter system. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2009; 2008:4859-62. [PMID: 19163805 DOI: 10.1109/iembs.2008.4650302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Conductance catheter system is used to estimate real-time ventricular volume by measuring the time-varying ventricular conductance/admittance. However, the system is generally calibrated only with known resistors, while neither the frequency response nor the bandwidth of the system is calibrated and measured. The main difficulty of measuring its bandwidth is that the sensed signal of the conductance catheter system, which can be viewed as the input of the system, is a modulated signal, rather than a typical sin wave. Therefore, its bandwidth cannot be measured by typical frequency response analyzers, since they are designed for pure sin-wave input. The waveform of the sensed signal is analyzed. Moreover, a waveform simulator designed to mimic the sensed signal is presented. It can be used to measure the bandwidth of conductance catheter system.
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Affiliation(s)
- Chieh-En Chen
- Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan
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48
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Raghavan K, Kottam ATG, Valvano JW, Pearce JA. Design of a wireless telemetric backpack device for real-time in vivo measurement of pressure-volume loops in conscious ambulatory rats. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2009; 2008:993-6. [PMID: 19162825 DOI: 10.1109/iembs.2008.4649322] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Pressure - Volume (PV) analysis is the de facto standard for assessing myocardial function. Conductance based methods have been used for the past 27 years to generate instantaneous left ventricular (LV) volume signal. Our research group has developed the instrumentation and the algorithm for obtaining PV loops based on the measurement of real - time admittance magnitude and phase from the LV of anaesthetized mice and rats. In this study, the instrumentation will be integrated into an ASIC (Application Specific Integrated Circuit) and a backpack device will be designed along with this ASIC. This will enable measurement of real-time in vivo P-V loops from conscious and ambulatory rats, useful for both acute and chronic studies.
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Affiliation(s)
- Karthik Raghavan
- Department of Electrical and Computer Engineering, ENS 634-A, C0803, The University of Texas at Austin, Austin, Texas 78712, USA.
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Análisis cuantitativo de la función ventricular izquierda como herramienta para la investigación clínica. Fundamentos y metodología. Rev Esp Cardiol 2009. [DOI: 10.1016/s0300-8932(09)71034-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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50
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Hoole SP, Khan SN, White PA, Heck PM, Kharbanda RK, Densem CG, Clarke SC, Shapiro LM, Schofield PM, O'Sullivan M, Dutka DP. Remote ischaemic pre-conditioning does not attenuate ischaemic left ventricular dysfunction in humans. Eur J Heart Fail 2009; 11:497-505. [DOI: 10.1093/eurjhf/hfp040] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Stephen P. Hoole
- Department of Cardiovascular Medicine; Addenbrooke's Hospital; ACCI, Level 6, Box 110, Hills Road Cambridge CB23 3RE UK
- Department of Cardiology; Papworth Hospital; Papworth Everard Cambridge CB3 8RE UK
| | - Sadia N. Khan
- Department of Cardiovascular Medicine; Addenbrooke's Hospital; ACCI, Level 6, Box 110, Hills Road Cambridge CB23 3RE UK
- Department of Cardiology; Papworth Hospital; Papworth Everard Cambridge CB3 8RE UK
| | - Paul A. White
- Department of Cardiology; Papworth Hospital; Papworth Everard Cambridge CB3 8RE UK
- Department of Medical Physics and Clinical Engineering; Addenbrooke's Hospital; Hills Road Cambridge CB2 0QQ UK
| | - Patrick M. Heck
- Department of Cardiovascular Medicine; Addenbrooke's Hospital; ACCI, Level 6, Box 110, Hills Road Cambridge CB23 3RE UK
- Department of Cardiology; Papworth Hospital; Papworth Everard Cambridge CB3 8RE UK
| | - Rajesh K. Kharbanda
- Department of Cardiovascular Medicine; Addenbrooke's Hospital; ACCI, Level 6, Box 110, Hills Road Cambridge CB23 3RE UK
| | - Cameron G. Densem
- Department of Cardiology; Papworth Hospital; Papworth Everard Cambridge CB3 8RE UK
| | - Sarah C. Clarke
- Department of Cardiology; Papworth Hospital; Papworth Everard Cambridge CB3 8RE UK
| | - Leonard M. Shapiro
- Department of Cardiology; Papworth Hospital; Papworth Everard Cambridge CB3 8RE UK
| | - Peter M. Schofield
- Department of Cardiology; Papworth Hospital; Papworth Everard Cambridge CB3 8RE UK
| | - Michael O'Sullivan
- Department of Cardiology; Papworth Hospital; Papworth Everard Cambridge CB3 8RE UK
| | - David P. Dutka
- Department of Cardiovascular Medicine; Addenbrooke's Hospital; ACCI, Level 6, Box 110, Hills Road Cambridge CB23 3RE UK
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