1
|
Chowdhury SM, Atz AM, Graham EM, Bandisode VM, Rhodes JF, Nutting AC, Taylor C, Savage A, Hassid M, Kavarana M, Menick D. Low Ventricular Stiffness Is Associated With Suboptimal Outcomes in Patients With a Single Right Ventricle After the Fontan Operation: A Novel Phenotype. J Am Heart Assoc 2024; 13:e035601. [PMID: 39189484 DOI: 10.1161/jaha.124.035601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Accepted: 07/09/2024] [Indexed: 08/28/2024]
Abstract
BACKGROUND Despite a rigorous screening process, including cardiac catheterization, a subset of patients with a single right ventricle (SRV) demonstrates suboptimal short-term outcomes after the Fontan operation. The goal of this study was to perform a comprehensive assessment of diastolic function in pre-Fontan patients with an SRV using invasive reference-standard measures and determine their associations with post-Fontan outcomes. METHODS AND RESULTS Children aged 2 to 6 years with SRV physiology undergoing pre-Fontan heart catheterization were recruited prospectively. Patients were divided into those who had an optimal or suboptimal outcome. A suboptimal outcome was defined as length of stay ≥14 days or heart transplant/cardiac death in first year after Fontan. Patients underwent pressure-volume loop analysis using reference-standard methods. The measure of ventricular stiffness, β, was obtained via preload reduction. Cardiac magnetic resonance imaging for extracellular volume and serum draws for matrix metalloproteinase activity were performed. Of 19 patients with an SRV, 9 (47%) had a suboptimal outcome. Mean age was 4.2±0.7 years. Patients with suboptimal outcomes had lower ventricular stiffness (0.021 [0.009-0.049] versus 0.090 [0.031-0.118] mL-1; P=0.02), lower extracellular volume (25% [28%-32%] versus 31% [28%-33%]; P=0.02), and lower matrix metalloproteinase-2 (90 [79-104] versus 108 [79-128] ng/mL; P=0.01) compared with patients with optimal outcomes. The only invasive measure that had an association with suboptimal outcome was β (P=0.038). CONCLUSIONS Patients with an SRV with suboptimal outcome after the Fontan operation had lower ventricular stiffness and evidence of maladaptive extracellular matrix metabolism compared with patients with optimal outcome. This appears to be a novel phenotype that may have important clinical implications and requires further study.
Collapse
Affiliation(s)
- Shahryar M Chowdhury
- Department of Pediatrics, Division of Cardiology Medical University of South Carolina Charleston SC USA
| | - Andrew M Atz
- Department of Pediatrics, Division of Cardiology Medical University of South Carolina Charleston SC USA
| | - Eric M Graham
- Department of Pediatrics, Division of Cardiology Medical University of South Carolina Charleston SC USA
| | - Varsha M Bandisode
- Department of Pediatrics, Division of Cardiology Medical University of South Carolina Charleston SC USA
| | - John F Rhodes
- Department of Pediatrics, Division of Cardiology Medical University of South Carolina Charleston SC USA
| | - Arni C Nutting
- Department of Pediatrics, Division of Cardiology Medical University of South Carolina Charleston SC USA
| | - Carolyn Taylor
- Department of Pediatrics, Division of Cardiology Medical University of South Carolina Charleston SC USA
| | - Andrew Savage
- Department of Pediatrics, Division of Cardiology Medical University of South Carolina Charleston SC USA
| | - Marc Hassid
- Department of Anesthesia Medical University of South Carolina Charleston SC USA
| | - Minoo Kavarana
- Department of Surgery Medical University of South Carolina Charleston SC USA
| | - Donald Menick
- Department of Medicine, Division of Cardiology Medical University of South Carolina Charleston SC USA
| |
Collapse
|
2
|
Abuiessa SA, Helmy MM, El-Gowelli HM, El-Gowilly SM, El-Mas MM. Gestationally administered RAS modulators reprogram endotoxic cardiovascular and inflammatory profiles in adult male offspring of preeclamptic rats. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2024:10.1007/s00210-024-03305-2. [PMID: 39046530 DOI: 10.1007/s00210-024-03305-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Accepted: 07/15/2024] [Indexed: 07/25/2024]
Abstract
Previous studies showed that preeclampsia (PE) amplifies cardiovascular dysfunction induced by endotoxemia in adult male, but not female, offspring. Here, we asked if such aggravated endotoxic insult could be nullified by modulators of the renin-angiotensin system (RAS). PE was induced by gestational administration of Nω-nitro-L-arginine methyl ester(L-NAME, a nitric oxide synthase inhibitor). Adult male offspring of PE mothers treated gestationally with angiotensin 1-7 (Ang1-7, angiotensin II-derived vasodilator), losartan (AT1 receptor antagonist), pioglitazone (peroxisome proliferator-activated receptor gamma, PPARγ, agonist), or combined losartan/pioglitazone were instrumented with femoral indwelling catheters and challenged intravenously with a 5-mg/kg dose of lipopolysaccharides (LPS, 5 mg/kg). LPS caused significant decreases in blood pressure (BP) and spectral index of overall heart rate variability and increases in heart rate and left ventricular contractility (dP/dtmax). These effects were mostly reduced to similar magnitudes by individual drug therapies. In offspring born to Ang1-7-treated dams, the spectral index of cardiac sympathovagal balance showed elevated sympathetic dominance in response to LPS. Immunohistochemistry revealed that Ang1-7, but not losartan/pioglitazone, abolished the exaggerated increases in toll-like receptor 4 (TLR-4) expression caused by PE/LPS in heart tissues and neuronal circuits of brainstem rostral ventrolateral medulla (RVLM). By contrast, the losartan/pioglitazone regimen, but not Ang1-7, decreased and increased angiotensin converting enzyme (ACE) and ACE2 expression, respectively. Together, gestational fetal reprogramming of Ang II (depression) and Ang1-7 (activation) arms of RAS effectively counterbalance worsened endotoxic cardiovascular and inflammatory profiles in adult male offspring of PE rats.
Collapse
Affiliation(s)
- Salwa A Abuiessa
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Mai M Helmy
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Hanan M El-Gowelli
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Sahar M El-Gowilly
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Mahmoud M El-Mas
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt.
- Department of Pharmacology and Toxicology, College of Medicine, Kuwait University, Al-Jabriyah Block 4, Hawally, Jabriya, Kuwait.
| |
Collapse
|
3
|
Monge García MI, Jian Z, Hatib F, Settles JJ, Cecconi M, Pinsky MR. Relationship between intraventricular mechanical dyssynchrony and left ventricular systolic and diastolic performance: An in vivo experimental study. Physiol Rep 2023; 11:e15607. [PMID: 36808901 PMCID: PMC9937795 DOI: 10.14814/phy2.15607] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 01/13/2023] [Accepted: 01/23/2023] [Indexed: 02/19/2023] Open
Abstract
Left ventricular mechanical dyssynchrony (LVMD) refers to the nonuniformity in mechanical contraction and relaxation timing in different ventricular segments. We aimed to determine the relationship between LVMD and LV performance, as assessed by ventriculo-arterial coupling (VAC), LV mechanical efficiency (LVeff ), left ventricular ejection fraction (LVEF), and diastolic function during sequential experimental changes in loading and contractile conditions. Thirteen Yorkshire pigs submitted to three consecutive stages with two opposite interventions each: changes in afterload (phenylephrine/nitroprusside), preload (bleeding/reinfusion and fluid bolus), and contractility (esmolol/dobutamine). LV pressure-volume data were obtained with a conductance catheter. Segmental mechanical dyssynchrony was assessed by global, systolic, and diastolic dyssynchrony (DYS) and internal flow fraction (IFF). Late systolic LVMD was related to an impaired VAC, LVeff , and LVEF, whereas diastolic LVMD was associated with delayed LV relaxation (logistic tau), decreased LV peak filling rate, and increased atrial contribution to LV filling. The hemodynamic factors related to LVMD were contractility, afterload, and heart rate. However, the relationship between these factors differed throughout the cardiac cycle. LVMD plays a significant role in LV systolic and diastolic performance and is associated with hemodynamic factors and intraventricular conduction.
Collapse
Affiliation(s)
| | | | | | | | - Maurizio Cecconi
- Department Anaesthesia and Intensive Care Units, Humanitas Research HospitalHumanitas UniversityMilanItaly
| | - Michael R. Pinsky
- Department of Critical Care MedicineUniversity of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
| |
Collapse
|
4
|
Dysregulated ACE/Ang II/Ang1-7 signaling provokes cardiovascular and inflammatory sequelae of endotoxemia in weaning preeclamptic rats. Eur J Pharmacol 2022; 936:175344. [DOI: 10.1016/j.ejphar.2022.175344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 10/07/2022] [Accepted: 10/17/2022] [Indexed: 11/22/2022]
|
5
|
Shima H, Nakaya T, Tsujino I, Nakamura J, Sugimoto A, Sato T, Watanabe T, Ohira H, Suzuki M, Kato M, Yokota I, Konno S. Accuracy of Swan‒Ganz catheterization‐based assessment of right ventricular function: Validation study using high‐fidelity micromanometry‐derived values as reference. Pulm Circ 2022; 12:e12078. [PMID: 35514782 PMCID: PMC9063972 DOI: 10.1002/pul2.12078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 03/15/2022] [Accepted: 04/06/2022] [Indexed: 11/14/2022] Open
Abstract
Right ventricular (RV) function critically affects the outcomes of patients with pulmonary hypertension (PH). Pressure wave analysis using Swan‒Ganz catheterization (SG‐cath) allows for the calculation of indices of RV function. However, the accuracy of these indices has not been validated. In the present study, we calculated indices of systolic and diastolic RV functions using SG‐cath‐derived pressure recordings in patients with suspected or confirmed PH. We analyzed and validated the accuracies of three RV indices having proven prognostic values, that is, end‐systolic elastance (Ees)/arterial elastance (Ea), β (stiffness constant), and end‐diastolic elastance (Eed), using high‐fidelity micromanometry‐derived data as reference. We analyzed 73 participants who underwent SG‐cath for the diagnosis or evaluation of PH. In this study, Ees/Ea was calculated via the single‐beat pressure method using [1.65 × (mean pulmonary arterial pressure) − 7.79] as end‐systolic pressure. SG‐cath‐derived Ees/Ea, β, and Eed were 0.89 ± 0.69 (mean ± standard deviation), 0.027 ± 0.002, and 0.16 ± 0.02 mmHg/ml, respectively. The mean differences (limits of agreement) between SG‐cath and micromanometry‐derived data were 0.13 (0.99, −0.72), 0.002 (0.020, −0.013), and 0.04 (0.20, −0.12) for Ees/Ea, β, and Eed, respectively. The intraclass correlation coefficients of the indices derived from the two catheterizations were 0.76, 0.71, and 0.57 for Ees/Ea, β, and Eed, respectively. In patients with confirmed or suspected PH, SG‐cath‐derived RV indices, especially Ees/Ea and β, exhibited a good correlation with micromanometry‐derived reference values.
Collapse
Affiliation(s)
- Hideki Shima
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
| | - Toshitaka Nakaya
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
| | - Ichizo Tsujino
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
- Division of Respiratory and Cardiovascular Innovative Research Faculty of Medicine, Hokkaido University Sapporo Japan
| | - Junichi Nakamura
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
| | - Ayako Sugimoto
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
| | - Takahiro Sato
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
- Division of Respiratory and Cardiovascular Innovative Research Faculty of Medicine, Hokkaido University Sapporo Japan
| | - Taku Watanabe
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
| | - Hiroshi Ohira
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
| | - Masaru Suzuki
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
| | - Masaru Kato
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine Hokkaido University Sapporo Japan
| | - Isao Yokota
- Department of Biostatistics, Graduate School of Medicine Hokkaido University Japan
| | - Satoshi Konno
- Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University Sapporo Japan
| |
Collapse
|
6
|
Abuiessa SA, El-Gowilly SM, El-Gowelli HM, Helmy MM, El-Mas MM. Short-lived sensitization of cardiovascular outcomes of postpartum endotoxemia in preeclamptic rats: Role of medullary solitary tract neuroinflammation. Eur J Pharmacol 2021; 910:174494. [PMID: 34508754 DOI: 10.1016/j.ejphar.2021.174494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 08/08/2021] [Accepted: 09/06/2021] [Indexed: 11/30/2022]
Abstract
Preeclampsia (PE) is a pregnancy-related disorder with serious maternal complications. Considering the increased importance of postpartum infection in maternal morbidity and mortality, we investigated whether preeclamptic maternal programming alters cardiovascular consequences of endotoxemia in rats and the role of cardiac and brainstem neuroinflammation in this interaction. Preeclampsia was induced by oral administration of L-NAME (50 mg/kg/day) for 7 days starting from day 14 of conception. Changes in blood pressure, heart rate, and cardiac autonomic function caused by lipopolysaccharide (LPS, 5 mg/kg i.v.) were assessed in mothers at 3 weeks (weaning time) and 9 weeks postnatally. Compared with respective non-PE counterparts, LPS treatment of weaning PE mothers caused significantly greater (i) falls in blood pressure, (ii) rises in heart rate and left ventricular contractility (dP/dtmax), (iii) reductions in time and frequency domain indices of heart rate variability and shifts in cardiac sympathovagal balance (low-frequency/high-frequency ratio, LF/HF) towards parasympathetic dominance, and (iv) attenuation of reflex bradycardic responses measured by the vasoactive method. The intensified LPS effects in weaning PE rats subsided after 9 weeks of delivery. Immunohistochemical studies showed increased protein expression of nuclear factor kappa B (NF-κB) in brainstem neuronal pools of the nucleus of the solitary tract (NTS), but not rostral ventrolateral medulla (RVLM), in endotoxic PE weaning rats compared with non-PE rats. Cardiac NF-κB expression was increased by LPS but this was similarly noted in PE and non-PE rats. Together, preeclamptic maternal programming elicits short-term exacerbation of endotoxic cardiovascular and autonomic derangements due possibly to exaggerated NTS neuroinflammatory insult.
Collapse
Affiliation(s)
- Salwa A Abuiessa
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Sahar M El-Gowilly
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Hanan M El-Gowelli
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Mai M Helmy
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Mahmoud M El-Mas
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; Department of Pharmacology and Toxicology, Faculty of Medicine, Kuwait University, Kuwait.
| |
Collapse
|
7
|
Sato T, Ambale-Venkatesh B, Zimmerman SL, Tedford RJ, Hsu S, Chamera E, Fujii T, Mullin CJ, Mercurio V, Khair R, Corona-Villalobos CP, Simpson CE, Damico RL, Kolb TM, Mathai SC, Lima JA, Kass DA, Tsujino I, Hassoun PM. Right ventricular function as assessed by cardiac magnetic resonance imaging-derived strain parameters compared to high-fidelity micromanometer catheter measurements. Pulm Circ 2021; 11:20458940211032529. [PMID: 34603686 PMCID: PMC8481729 DOI: 10.1177/20458940211032529] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 06/17/2021] [Indexed: 11/16/2022] Open
Abstract
Right ventricular function has prognostic significance in patients with pulmonary hypertension. We evaluated whether cardiac magnetic resonance-derived strain and strain rate parameters could reliably reflect right ventricular systolic and diastolic function in precapillary pulmonary hypertension. End-systolic elastance and the time constant of right ventricular relaxation tau, both derived from invasive high-fidelity micromanometer catheter measurements, were used as gold standards for assessing systolic and diastolic right ventricular function, respectively. Nineteen consecutive precapillary pulmonary hypertension patients underwent cardiac magnetic resonance and right heart catheterization prospectively. Cardiac magnetic resonance data were compared with those of 19 control subjects. In pulmonary hypertension patients, associations between strain- and strain rate-related parameters and invasive hemodynamic parameters were evaluated. Longitudinal peak systolic strain, strain rate, and early diastolic strain rate were lower in PAH patients than in controls; peak atrial-diastolic strain rate was higher in pulmonary hypertension patients. Similarly, circumferential peak systolic strain rate was lower and peak atrial-diastolic strain rate was higher in pulmonary hypertension. In pulmonary hypertension, no correlations existed between cardiac magnetic resonance-derived and hemodynamically derived measures of systolic right ventricular function. Regarding diastolic parameters, tau was significantly correlated with peak longitudinal atrial-diastolic strain rate (r = -0.61), deceleration time (r = 0.75), longitudinal systolic to diastolic time ratio (r = 0.59), early diastolic strain rate (r = -0.5), circumferential peak atrial-diastolic strain rate (r = -0.52), and deceleration time (r = 0.62). Strain analysis of the right ventricular diastolic phase is a reliable non-invasive method for detecting right ventricular diastolic dysfunction in PAH.
Collapse
Affiliation(s)
- Takahiro Sato
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Bharath Ambale-Venkatesh
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Stefan L. Zimmerman
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ryan J. Tedford
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Steven Hsu
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ela Chamera
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Tomoki Fujii
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | - Valentina Mercurio
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Rubina Khair
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Celia P. Corona-Villalobos
- Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Catherine E. Simpson
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Rachel L. Damico
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Todd M. Kolb
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Stephen C. Mathai
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Joao A.C. Lima
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - David A. Kass
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ichizo Tsujino
- First Department of Medicine, Hokkaido University Hospital, Sapporo, Japan
| | - Paul M. Hassoun
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| |
Collapse
|
8
|
Linden K, Winkler C, Breuer J, Herberg U. Assessment of pressure-volume relations in univentricular hearts: Comparison of obtainment by real-time 3D echocardiography and mini pressure-wire with conductance technology. PLoS One 2021; 16:e0246031. [PMID: 33524066 PMCID: PMC7850469 DOI: 10.1371/journal.pone.0246031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 01/12/2021] [Indexed: 11/18/2022] Open
Abstract
Objectives The gold standard to obtain pressure-volume relations (PVR) of the heart, the conductance technology (PVRCond), is rarely used in children. PVR can also be obtained by 3D-echocardiography volume data combined with simultaneously measured pressure data by a mini pressure-wire (PVR3DE). We sought to investigate the feasibility of both methods in patients with univentricular hearts and to compare them, including hemodynamic changes. Methods We studied 19 patients (age 2–29 years). PVR3DE and PVRCond were assessed under baseline conditions and stimulation with dobutamine. Results Obtaining PVR3DE was successful in all patients. Obtaining PVRCond was possible in 15 patients during baseline (79%) and in 12 patients under dobutamine (63%). Both methods showed that end-systolic elastance (Ees) and arterial elastance (Ea) increased under dobutamine and that Tau showed a statistically significant decrease. Intraclass correlation (95% confidence interval) showed moderate to good agreement between methods: Ees: 0.873 (0.711–0.945), Ea: 0.709 (0.336–0.873), Tau: 0.867 (0.697–0.942). Bland-Altman analyses showed an acceptable bias with wider limits of agreement: Ees: 1.63 mmHg/ml (-3.83–7.08 mmHg/ml), Ea: 0.53 mmHg/ml (-5.23–6.28 mmHg/ml), Tau: -0,76 ms (-10.73–9.21 ms). Conclusion Changes of PVR-specific parameters under dobutamine stimulation were reflected in the same way by both methods. However, the absolute values for these parameters could vary between methods and, therefore, methods are not interchangeable. Obtaining PVR3DE in a single ventricle was easier, faster and more successful than PVRCond. PVR3DE provides a promising and needed alternative to the conductance technology for the assessment of cardiac function in univentricular hearts.
Collapse
Affiliation(s)
- Katharina Linden
- Department of Pediatric Cardiology, Children’s Hospital, University Hospital Bonn, Bonn, Germany
- * E-mail:
| | - Christian Winkler
- Department of Pediatric Cardiology, Children’s Hospital, University Hospital Bonn, Bonn, Germany
| | - Johannes Breuer
- Department of Pediatric Cardiology, Children’s Hospital, University Hospital Bonn, Bonn, Germany
| | - Ulrike Herberg
- Department of Pediatric Cardiology, Children’s Hospital, University Hospital Bonn, Bonn, Germany
| |
Collapse
|
9
|
Lakomkin VL, Lukoshkina EV, Kapelko VI. Reaction of the Heart to High Frequency Stimulation against the Background of Acute Doxorubicin Treatment. Bull Exp Biol Med 2020; 169:619-622. [PMID: 32986211 DOI: 10.1007/s10517-020-04940-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Indexed: 01/19/2023]
Abstract
Short-term high frequency electrostimulation (8-10 Hz) of the isolated isovolumic rat heart rapidly increased the rate of pressure rise and drop and the diastolic pressure. At the same time, the relaxation rate constant (RRC), being independent of the developed pressure, remained unaltered. These findings suggested that diastolic pressure rise was not caused by incomplete myocardial relaxation. Doxorubicin (3 μM) moderately reduced the developed pressure, but the relaxation rate constant remained unchanged. The dynamics and degree of changes in all indicators of the cardiac contractile function in high-frequency stimulation were the same as in control. It can be hypothesized that the initial effect of doxorubicin was not related to ionic transport system disturbances in cardiomyocytes.
Collapse
Affiliation(s)
- V L Lakomkin
- National Medical Research Center of Cardiology, Ministry of Health of the Russian Federation, Moscow, Russia.
| | - E V Lukoshkina
- National Medical Research Center of Cardiology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - V I Kapelko
- National Medical Research Center of Cardiology, Ministry of Health of the Russian Federation, Moscow, Russia
| |
Collapse
|
10
|
Nagueh SF. Heart failure with preserved ejection fraction: insights into diagnosis and pathophysiology. Cardiovasc Res 2020; 117:999-1014. [PMID: 32717061 DOI: 10.1093/cvr/cvaa228] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/15/2020] [Accepted: 07/21/2020] [Indexed: 12/14/2022] Open
Abstract
Heart failure with preserved ejection fraction (HFpEF) accounts for at least half the cases of heart failure, currently diagnosed. There are several cardiac and non-cardiac manifestations of the syndrome. Structure and function abnormalities can include all four cardiac chambers. The left ventricle has abnormal systolic and diastolic functions which can be examined by invasive and non-invasive measurements. In addition, the left atrium enlarges with abnormal left atrial function, pulmonary hypertension occurs, and the right ventricle can develop hypertrophy, enlargement, and systolic dysfunction. There are a paucity of data on calcium handling in HFpEF patients. Growing literature supports the presence of abnormalities in titin and its phosphorylation, and increased interstitial fibrosis contributing to increased chamber stiffness. A systemic inflammatory state causing reduced myocardial cyclic guanosine monophosphate along with defects in the unfolded protein response have been recently reported. Diagnosis relies on signs and symptoms of heart failure, preserved ejection fraction, and detection of diastolic function abnormalities based on echocardiographic findings and abnormally elevated natriuretic peptide levels or invasive measurements of wedge pressure at rest or with exercise. There are currently two diagnostic algorithms: H2FPEF, and HFA-PEFF with limited data comparing their performance head to head in the same patient population. Despite the growing understanding of the syndrome's pathophysiology, there have been little success in developing specific treatment for patients with HFpEF.
Collapse
Affiliation(s)
- Sherif F Nagueh
- Methodist DeBakey Heart and Vascular Center, 6550 Fannin, SM-1801, Houston, TX 77030, USA
| |
Collapse
|
11
|
Ogilvie LM, Edgett BA, Huber JS, Platt MJ, Eberl HJ, Lutchmedial S, Brunt KR, Simpson JA. Hemodynamic assessment of diastolic function for experimental models. Am J Physiol Heart Circ Physiol 2020; 318:H1139-H1158. [PMID: 32216614 DOI: 10.1152/ajpheart.00705.2019] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Traditionally, the evaluation of cardiac function has focused on systolic function; however, there is a growing appreciation for the contribution of diastolic function to overall cardiac health. Given the emerging interest in evaluating diastolic function in all models of heart failure, there is a need for sensitivity, accuracy, and precision in the hemodynamic assessment of diastolic function. Hemodynamics measure cardiac pressures in vivo, offering a direct assessment of diastolic function. In this review, we summarize the underlying principles of diastolic function, dividing diastole into two phases: 1) relaxation and 2) filling. We identify parameters used to comprehensively evaluate diastolic function by hemodynamics, clarify how each parameter is obtained, and consider the advantages and limitations associated with each measure. We provide a summary of the sensitivity of each diastolic parameter to loading conditions. Furthermore, we discuss differences that can occur in the accuracy of diastolic and systolic indices when generated by automated software compared with custom software analysis and the magnitude each parameter is influenced during inspiration with healthy breathing and a mild breathing load, commonly expected in heart failure. Finally, we identify key variables to control (e.g., body temperature, anesthetic, sampling rate) when collecting hemodynamic data. This review provides fundamental knowledge for users to succeed in troubleshooting and guidelines for evaluating diastolic function by hemodynamics in experimental models of heart failure.
Collapse
Affiliation(s)
- Leslie M Ogilvie
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada.,IMPART Investigator Team Canada, Saint John, New Brunswick, Canada
| | - Brittany A Edgett
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada.,Department of Pharmacology, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada.,IMPART Investigator Team Canada, Saint John, New Brunswick, Canada
| | - Jason S Huber
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Mathew J Platt
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Hermann J Eberl
- Department of Mathematics and Statistics, University of Guelph, Guelph, Ontario, Canada
| | - Sohrab Lutchmedial
- Department of Pharmacology, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada.,Department of Cardiology, New Brunswick Heart Center, Saint John Regional Hospital, Horizon Health Network, Saint John, New Brunswick, Canada
| | - Keith R Brunt
- Department of Pharmacology, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada.,IMPART Investigator Team Canada, Saint John, New Brunswick, Canada
| | - Jeremy A Simpson
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada.,IMPART Investigator Team Canada, Saint John, New Brunswick, Canada
| |
Collapse
|
12
|
Obata K, Morita H, Takaki M. Mechanism underlying the negative inotropic effect in rat left ventricle in hyperthermia: the role of TRPV1. J Physiol Sci 2020; 70:4. [PMID: 32039693 PMCID: PMC7002332 DOI: 10.1186/s12576-020-00734-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 12/09/2019] [Indexed: 01/10/2023]
Abstract
We have previously reported that the negative inotropic effects of hyperthermia (42 °C) on left ventricular (LV) mechanoenergetics using the excised, cross-circulated rat heart model. Here, we investigated the role of TRPV1 on LV mechanoenergetics in hyperthermia. We analyzed the LV end-systolic pressure–volume relation (ESPVR) and the linear relation between the myocardial oxygen consumption per beat (VO2) and the systolic pressure–volume area (PVA; a total mechanical energy per beat) during infusion of capsazepine (CPZ) in hyperthermia, or capsaicin (Cap) under 300 bpm pacing. LV ESP decreased in each LV volume and the resultant downward-shift of LV ESPVR was suppressed by CPZ infusion in hyperthermia-hearts. In Cap-treated hearts, LV ESPVR shifted downward from the control ESPVR, similar to hyperthermia-hearts. The slopes of VO2–PVA relationship were unchanged. The VO2 intercepts in hyperthermia-hearts did not decrease because of decreased E–C coupling VO2, and inversely increased basal metabolic VO2, which was suppressed by CPZ, though the VO2 intercepts in Cap-treated hearts significantly decreased. The levels of phosphorylated phospholamban at serine 16 decreased significantly in hyperthermia-hearts, as well as Cap-treated hearts. These results indicate that a Cap-induced decrease in the LV contractility, like in cases of hyperthermia, are due to the down-regulation of the total calcium handling in E–C coupling, suggesting that negative inotropic effect in hyperthermia-heart is, at least in part, mediated through TRPV1 signaling pathway.
Collapse
Affiliation(s)
- Koji Obata
- Department of Physiology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan.
| | - Hironobu Morita
- Department of Physiology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan
| | - Miyako Takaki
- Department of Physiology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan
| |
Collapse
|
13
|
Hayabuchi Y. Right ventricular myocardial stiffness and relaxation components by kinematic model-based analysis. THE JOURNAL OF MEDICAL INVESTIGATION 2020; 67:11-20. [DOI: 10.2152/jmi.67.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Yasunobu Hayabuchi
- Department of Pediatrics, Department of Pediatrics and community medicine, Tokushima University, Tokushima, Japan
| |
Collapse
|
14
|
Sallam MY, El-Gowilly SM, Fouda MA, Abd-Alhaseeb MM, El-Mas MM. Brainstem cholinergic pathways diminish cardiovascular and neuroinflammatory actions of endotoxemia in rats: Role of NFκB/α7/α4β2AChRs signaling. Neuropharmacology 2019; 157:107683. [DOI: 10.1016/j.neuropharm.2019.107683] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 06/16/2019] [Accepted: 06/23/2019] [Indexed: 12/20/2022]
|
15
|
Giblett JP, Axell RG, White PA, Aetesam-Ur-Rahman M, Clarke SJ, Figg N, Bennett MR, West NEJ, Hoole SP. Glucagon-Like Peptide-1-Mediated Cardioprotection Does Not Reduce Right Ventricular Stunning and Cumulative Ischemic Dysfunction After Coronary Balloon Occlusion. ACTA ACUST UNITED AC 2019; 4:222-233. [PMID: 31061924 PMCID: PMC6488814 DOI: 10.1016/j.jacbts.2018.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 12/07/2018] [Accepted: 12/10/2018] [Indexed: 11/28/2022]
Abstract
GLP-1 protects against ischemic left ventricular dysfunction after serial coronary balloon occlusion of the left anterior descending artery This study assessed whether serial right coronary artery balloon occlusion affected the right ventricle in a similar fashion using a conductance catheter method Serial balloon occlusion of the right coronary artery causes stunning and cumulative ischemic dysfunction in the right ventricle GLP-1 did not protect against stunning and cumulative ischemic dysfunction in the right ventricle
Stunning and cumulative ischemic dysfunction occur in the left ventricle with coronary balloon occlusion. Glucagon-like peptide (GLP)-1 protects the left ventricle against this dysfunction. This study used a conductance catheter method to evaluate whether the right ventricle (RV) developed similar dysfunction during right coronary artery balloon occlusion and whether GLP-1 was protective. In this study, the RV underwent significant stunning and cumulative ischemic dysfunction with right coronary artery balloon occlusion. However, GLP-1 did not protect the RV against this dysfunction when infused after balloon occlusion.
Collapse
Key Words
- BL, baseline
- BO1, first balloon occlusion
- BO2, second balloon occlusion
- DSHB, Developmental Studies Hybridoma Bank
- EDP, end-diastolic pressure
- GLP, glucagon-like peptide
- GLP-1R, glucagon-like peptide 1 receptor
- LV, left ventricular
- PCI, percutaneous coronary intervention
- PV, pressure–volume
- RCA, right coronary artery
- RV, right ventricular
- Tau, time constant of diastolic relaxation
- cardioprotection
- dP/dtmax, maximal rate of isovolumetric contraction
- dP/dtmin, maximal rate of isovolumetric relaxation
- glucagon-like peptide-1
- ischemia-reperfusion injury
- right ventricle
Collapse
Affiliation(s)
- Joel P Giblett
- Department of Interventional Cardiology, Royal Papworth Hospital, Cambridge, United Kingdom.,Division of Cardiovascular Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Richard G Axell
- Medical Physics and Clinical Engineering, Cambridge University Hospital NHS Foundation Trust, Cambridge, United Kingdom
| | - Paul A White
- Medical Physics and Clinical Engineering, Cambridge University Hospital NHS Foundation Trust, Cambridge, United Kingdom
| | - Muhammad Aetesam-Ur-Rahman
- Department of Interventional Cardiology, Royal Papworth Hospital, Cambridge, United Kingdom.,Division of Cardiovascular Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Sophie J Clarke
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Nicola Figg
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Martin R Bennett
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Nick E J West
- Department of Interventional Cardiology, Royal Papworth Hospital, Cambridge, United Kingdom
| | - Stephen P Hoole
- Department of Interventional Cardiology, Royal Papworth Hospital, Cambridge, United Kingdom.,Division of Cardiovascular Medicine, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
16
|
Obata K, Takeshita D, Morita H, Takaki M. Left ventricular mechanoenergetics in excised, cross-circulated rat hearts under hypo-, normo-, and hyperthermic conditions. Sci Rep 2018; 8:16246. [PMID: 30390094 PMCID: PMC6214925 DOI: 10.1038/s41598-018-34666-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 10/22/2018] [Indexed: 11/27/2022] Open
Abstract
We investigated the effects of altering cardiac temperature on left ventricular (LV) myocardial mechanical work and energetics using the excised, cross-circulated rat heart model. We analyzed the LV end-systolic pressure-volume relationship (ESPVR) and linear relationship between myocardial oxygen consumption per beat (VO2) and systolic pressure-volume area (PVA; total mechanical energy per beat) in isovolumically contracting rat hearts during hypo- (32 °C), normo- (37 °C), and hyperthermia (42 °C) under a 300-beats per minute pacing. LV ESPVR shifted downward with increasing cardiac temperature. The VO2-PVA relationship was superimposable in these different thermal conditions; however, each data point of VO2-PVA shifted left-downward during increasing cardiac temperature on the superimposable VO2-PVA relationship line. VO2 for Ca2+ handling in excitation-contraction coupling decreased, which was associated with increasing cardiac temperature, during which sarcoplasmic reticulum Ca2+-ATPase (SERCA) activity was suppressed, due to phospholamban phosphorylation inhibition, and instead, O2 consumption for basal metabolism was increased. The O2 cost of LV contractility for Ca2+ also increased with increasing cardiac temperature. Logistic time constants evaluating LV relaxation time were significantly shortened with increasing cardiac temperature related to the acceleration of the detachment in cross-bridge (CB) cycling, indicating increased myosin ATPase activity. The results suggested that increasing cardiac temperature induced a negative inotropic action related to SERCA activity suppression in Ca2+ handling and increased myosin ATPase activity in CB cycling. We concluded that thermal intervention could modulate cardiac inotropism by changing CB cycling, Ca2+ handling, and basal metabolism in rat hearts.
Collapse
Affiliation(s)
- Koji Obata
- Department of Physiology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan.
| | - Daisuke Takeshita
- Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, Suita, 565-8565, Japan
| | - Hironobu Morita
- Department of Physiology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan
| | - Miyako Takaki
- Department of Physiology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan
- Department of Orthopaedic Surgery, Nara Medical University, School of Medicine, 840 Shijo-cho, Kashihara, Nara, 634-8521, Japan
| |
Collapse
|
17
|
Ibrahim KS, El-Yazbi AF, El-Gowelli HM, El-Mas MM. Heme oxygenase byproducts variably influences myocardial and autonomic dysfunctions induced by the cyclosporine/diclofenac regimen in female rats. Biomed Pharmacother 2018; 101:889-897. [DOI: 10.1016/j.biopha.2018.03.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/04/2018] [Accepted: 03/06/2018] [Indexed: 12/15/2022] Open
|
18
|
Hayabuchi Y, Ono A, Homma Y, Kagami S. Analysis of Right Ventricular Myocardial Stiffness and Relaxation Components in Children and Adolescents With Pulmonary Arterial Hypertension. J Am Heart Assoc 2018; 7:JAHA.118.008670. [PMID: 29674337 PMCID: PMC6015282 DOI: 10.1161/jaha.118.008670] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background The rate of left ventricular pressure decrease during isovolumic relaxation is traditionally assessed algebraically via 2 empirical indices: the monoexponential and logistic time constants (τE and τL). Since the pattern of right ventricular (RV) pressure decrease is quite different from that of the left ventricular, we hypothesized that novel kinematic model parameters are more appropriate and useful to evaluate RV diastolic dysfunction. Methods and Results Eight patients with pulmonary arterial hypertension (age 12.5±4.8 years) and 20 normal subjects (control group; age 12.3±4.4 years) were enrolled. The kinematic model was parametrized by stiffness/restoring Ek and damping/relaxation μ. The model predicts isovolumic relaxation pressure as a function of time as the solution of d2P/dt2+(1/μ)dP/dt+EkP=0, based on the theory that the pressure decay is determined by the interplay of inertial, stiffness/restoring, and damping/relaxation forces. In the assessment of RV diastolic function, τE and τL did not show significant differences between the pulmonary arterial hypertension and control groups (46.8±15.5 ms versus 32.5±14.6 ms, and 19.6±5.9 ms versus 14.5±7.2 ms, respectively). The pulmonary arterial hypertension group had a significantly higher Ek than the control group (915.9±84.2 s−2 versus 487.0±99.6 s−2, P<0.0001) and a significantly lower μ than the control group (16.5±4.3 ms versus 41.1±10.4 ms, P<0.0001). These results show that the RV has higher stiffness/elastic recoil and lower cross‐bridge relaxation in pulmonary arterial hypertension. Conclusions The present findings indicate the feasibility and utility of kinematic model parameters for assessing RV diastolic function.
Collapse
Affiliation(s)
| | - Akemi Ono
- Department of Pediatrics, Tokushima University, Tokushima, Japan
| | - Yukako Homma
- Department of Pediatrics, Tokushima University, Tokushima, Japan
| | - Shoji Kagami
- Department of Pediatrics, Tokushima University, Tokushima, Japan
| |
Collapse
|
19
|
Nakaya T, Tsujino I, Ohira H, Sato T, Watanabe T, Oyama-Manabe N, Nishimura M. Amelioration of right ventricular systolic function and stiffness in a patient with idiopathic pulmonary arterial hypertension treated with oral triple combination therapy. Pulm Circ 2018; 8:2045894018765350. [PMID: 29488427 PMCID: PMC5858733 DOI: 10.1177/2045894018765350] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Right ventricular (RV) function is an important determinant of the prognosis in patients with pulmonary arterial hypertension (PAH). In the context of recent therapeutic progress, there is an increasing need for better monitoring of RV function for management of PAH. We present the case of a 42-year-old woman with idiopathic PAH who was treated with three oral pulmonary vasodilators, i.e. tadalafil, ambrisentan, and beraprost. At the baseline assessment, the mean pulmonary arterial pressure (mPAP) was 45 mmHg, cardiac index (CI) was 1.36 L/min/m2, and pulmonary vascular resistance (PVR) was elevated to 21.3 Wood units (WU). However, three months after the start of combination treatment, mPAP and PVR decreased to 42 mmHg and 7.5 WU, respectively, and conventional indices of RV function, such as CI, right atrial area, and right atrial pressure also improved. Beyond three months, however, there were no further improvements in mPAP, PVR, or indices of RV function. In addition, we calculated three recently introduced indices of intrinsic RV function: end-systolic elastance (Ees; an index of RV contractility), Ees/arterial elastance ratio (Ees/Ea; an index of RV/pulmonary arterial coupling), and β (an index of RV stiffness) using cardiac magnetic resonance imaging and Swan-Ganz catheterization measurements. Notably, in contrast to conventional parameters, Ees, Ees/Ea, and β showed persistent improvement during the entire two-year follow-up. The application of Ees, Ees/Ea, and β may play an additional role in a comprehensive assessment of RV function in PAH.
Collapse
Affiliation(s)
- Toshitaka Nakaya
- 1 1466 First Department of Medicine, Hokkaido University Hospital, Sapporo, Japan
| | - Ichizo Tsujino
- 1 1466 First Department of Medicine, Hokkaido University Hospital, Sapporo, Japan
| | - Hiroshi Ohira
- 1 1466 First Department of Medicine, Hokkaido University Hospital, Sapporo, Japan
| | - Takahiro Sato
- 1 1466 First Department of Medicine, Hokkaido University Hospital, Sapporo, Japan
| | - Taku Watanabe
- 1 1466 First Department of Medicine, Hokkaido University Hospital, Sapporo, Japan
| | - Noriko Oyama-Manabe
- 2 Department of Diagnostic and Interventional Radiology, Hokkaido University Hospital, Sapporo, Japan
| | - Masaharu Nishimura
- 1 1466 First Department of Medicine, Hokkaido University Hospital, Sapporo, Japan
| |
Collapse
|
20
|
Chowdhury SM, Butts RJ, Hlavacek AM, Taylor CL, Chessa KS, Bandisode VM, Shirali GS, Nutting A, Baker GH. Echocardiographic Detection of Increased Ventricular Diastolic Stiffness in Pediatric Heart Transplant Recipients: A Pilot Study. J Am Soc Echocardiogr 2017; 31:342-348.e1. [PMID: 29246510 DOI: 10.1016/j.echo.2017.11.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND Pediatric heart transplant recipients are at risk for increased left ventricular (LV) diastolic stiffness. However, the noninvasive evaluation of LV stiffness has remained elusive in this population. The objective of this study was to compare novel echocardiographic measures of LV diastolic stiffness versus gold-standard measures derived from pressure-volume loop (PVL) analysis in pediatric heart transplant recipients. METHODS Patients undergoing left heart catheterization were prospectively enrolled. PVLs were obtained via conductance. The end-diastolic pressure-volume relationship was obtained via balloon occlusion. The stiffness constant, β, was calculated. Echocardiographic measures of diastolic function were derived from spectral and tissue Doppler and two-dimensional speckle-tracking. Ventricular volumes were measured using three-dimensional echocardiography. The novel echocardiographic estimates of ventricular stiffness included E:e'/end-diastolic volume (EDV) and E:early diastolic strain rate/EDV. RESULTS Of 24 children, 18 were heart transplant recipients. Six control patients had hemodynamically insignificant patent ductus arteriosus or coronary fistula. The mean age was 9.1 ± 5.6 years. Median end-diastolic pressure was 9 mm Hg (interquartile range, 8-13 mm Hg). Lateral E:e'/EDV (r = 0.59, P < .01), septal E:e'/EDV (r = 0.57, P < .01), and (E:circumferential early diastolic strain rate)/EDV (r = 0.54, P < .01) correlated with β. Lateral E:e'/EDV displayed a C statistic of 0.93 in detecting patients with abnormal LV stiffness (β > 0.015 mL-1). A lateral E:e'/EDV of >0.15 mL-1 had 89% sensitivity and 93% specificity in detecting an abnormal β. CONCLUSIONS Echocardiographic estimates of ventricular stiffness may be accurate compared with the gold standard in pediatric heart transplant recipients. The clinical usefulness of these noninvasive measures in assessing LV stiffness merits further study in children.
Collapse
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, UT Southwestern Medical Center, Dallas, Texas
| | - Anthony M Hlavacek
- 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
| | - Karen S Chessa
- 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
| | - Girish S Shirali
- The Ward Family Heart Center, Children's Mercy Hospital, Kansas City, Missouri
| | - Arni Nutting
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina
| | - G Hamilton Baker
- Department of Pediatrics, Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina
| |
Collapse
|
21
|
Axell RG, Messer SJ, White PA, McCabe C, Priest A, Statopoulou T, Drozdzynska M, Viscasillas J, Hinchy EC, Hampton-Till J, Alibhai HI, Morrell N, Pepke-Zaba J, Large SR, Hoole SP. Ventriculo-arterial coupling detects occult RV dysfunction in chronic thromboembolic pulmonary vascular disease. Physiol Rep 2017; 5:5/7/e13227. [PMID: 28373412 PMCID: PMC5392517 DOI: 10.14814/phy2.13227] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 02/09/2017] [Accepted: 02/26/2017] [Indexed: 01/24/2023] Open
Abstract
Chronic thromboembolic disease (CTED) is suboptimally defined by a mean pulmonary artery pressure (mPAP) <25 mmHg at rest in patients that remain symptomatic from chronic pulmonary artery thrombi. To improve identification of right ventricular (RV) pathology in patients with thromboembolic obstruction, we hypothesized that the RV ventriculo-arterial (Ees/Ea) coupling ratio at maximal stroke work (Ees/Eamax sw) derived from an animal model of pulmonary obstruction may be used to identify occult RV dysfunction (low Ees/Ea) or residual RV energetic reserve (high Ees/Ea). Eighteen open chested pigs had conductance catheter RV pressure-volume (PV)-loops recorded during PA snare to determine Ees/Eamax sw This was then applied to 10 patients with chronic thromboembolic pulmonary hypertension (CTEPH) and ten patients with CTED, also assessed by RV conductance catheter and cardiopulmonary exercise testing. All patients were then restratified by Ees/Ea. The animal model determined an Ees/Eamax sw = 0.68 ± 0.23 threshold, either side of which cardiac output and RV stroke work fell. Two patients with CTED were identified with an Ees/Ea well below 0.68 suggesting occult RV dysfunction whilst three patients with CTEPH demonstrated Ees/Ea ≥ 0.68 suggesting residual RV energetic reserve. Ees/Ea > 0.68 and Ees/Ea < 0.68 subgroups demonstrated constant RV stroke work but lower stroke volume (87.7 ± 22.1 vs. 60.1 ± 16.3 mL respectively, P = 0.006) and higher end-systolic pressure (36.7 ± 11.6 vs. 68.1 ± 16.7 mmHg respectively, P < 0.001). Lower Ees/Ea in CTED also correlated with reduced exercise ventilatory efficiency. Low Ees/Ea aligns with features of RV maladaptation in CTED both at rest and on exercise. Characterization of Ees/Ea in CTED may allow for better identification of occult RV dysfunction.
Collapse
Affiliation(s)
- Richard G Axell
- Medical Physics and Clinical Engineering, Cambridge University Hospital NHS Foundation Trust, Cambridge, UK.,Postgraduate Medical Institute, Anglia Ruskin University, Chelmsford, UK
| | - Simon J Messer
- Department of Cardiovascular Surgery, Papworth Hospital NHS Foundation Trust, Cambridge, UK
| | - Paul A White
- Medical Physics and Clinical Engineering, Cambridge University Hospital NHS Foundation Trust, Cambridge, UK.,Postgraduate Medical Institute, Anglia Ruskin University, Chelmsford, UK
| | - Colm McCabe
- Pulmonary Vascular Diseases Unit, Papworth Hospital NHS Foundation Trust, Cambridge, UK
| | - Andrew Priest
- Medical Physics and Clinical Engineering, Cambridge University Hospital NHS Foundation Trust, Cambridge, UK
| | | | | | | | - Elizabeth C Hinchy
- MRC Mitochondrial Biology Unit, Cambridge Biomedical Campus, Cambridge, UK
| | - James Hampton-Till
- Postgraduate Medical Institute, Anglia Ruskin University, Chelmsford, UK
| | | | - Nicholas Morrell
- Pulmonary Vascular Diseases Unit, Papworth Hospital NHS Foundation Trust, Cambridge, UK
| | - Joanna Pepke-Zaba
- Pulmonary Vascular Diseases Unit, Papworth Hospital NHS Foundation Trust, Cambridge, UK
| | - Stephen R Large
- Department of Cardiovascular Surgery, Papworth Hospital NHS Foundation Trust, Cambridge, UK
| | - Stephen P Hoole
- Department of Interventional Cardiology, Papworth Hospital NHS Foundation Trust, Cambridge, UK
| |
Collapse
|
22
|
El-Bassossy HM, Awan Z, El-Mas MM. Perinatal ciclosporin A exposure elicits sex-related cardiac dysfunction and inflammation in the rat progeny. Toxicol Lett 2017; 281:35-43. [DOI: 10.1016/j.toxlet.2017.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Revised: 09/03/2017] [Accepted: 09/04/2017] [Indexed: 12/19/2022]
|
23
|
Axell RG, Giblett JP, White PA, Klein A, Hampton-Til J, O'Sullivan M, Braganza D, Davies WR, West NEJ, Densem CG, Hoole SP. Stunning and Right Ventricular Dysfunction Is Induced by Coronary Balloon Occlusion and Rapid Pacing in Humans: Insights From Right Ventricular Conductance Catheter Studies. J Am Heart Assoc 2017; 6:JAHA.117.005820. [PMID: 28588092 PMCID: PMC5669185 DOI: 10.1161/jaha.117.005820] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Background We sought to determine whether right ventricular stunning could be detected after supply (during coronary balloon occlusion [BO]) and supply/demand ischemia (induced by rapid pacing [RP] during transcatheter aortic valve replacement) in humans. Methods and Results Ten subjects with single‐vessel right coronary artery disease undergoing percutaneous coronary intervention with normal ventricular function were studied in the BO group. Ten subjects undergoing transfemoral transcatheter aortic valve replacement were studied in the RP group. In both, a conductance catheter was placed into the right ventricle, and pressure volume loops were recorded at baseline and for intervals over 15 minutes after a low‐pressure BO for 1 minute or a cumulative duration of RP for up to 1 minute. Ischemia‐induced diastolic dysfunction was seen 1 minute after RP (end‐diastolic pressure [mm Hg]: 8.1±4.2 versus 12.1±4.1, P<0.001) and BO (end‐diastolic pressure [mm Hg]: 8.1±4.0 versus 8.7±4.0, P=0.03). Impairment of systolic and diastolic function after BO remained at 15‐minutes recovery (ejection fraction [%]: 55.7±9.0 versus 47.8±6.3, P<0.01; end‐diastolic pressure [mm Hg]: 8.1±4.0 versus 9.2±3.9, P<0.01). Persistent diastolic dysfunction was also evident in the RP group at 15‐minutes recovery (end‐diastolic pressure [mm Hg]: 8.1±4.1 versus 9.9±4.4, P=0.03) and there was also sustained impairment of load‐independent indices of systolic function at 15 minutes after RP (end‐systolic elastance and ventriculo‐arterial coupling [mm Hg/mL]: 1.25±0.31 versus 0.85±0.43, P<0.01). Conclusions RP and right coronary artery balloon occlusion both cause ischemic right ventricular dysfunction with stunning observed later during the procedure. This may have intraoperative implications in patients without right ventricular functional reserve.
Collapse
Affiliation(s)
- Richard G Axell
- Medical Physics and Clinical Engineering, Cambridge University Hospital NHS Foundation Trust, Cambridge, United Kingdom.,Postgraduate Medical Institute, Anglia Ruskin University, Chelmsford, United Kingdom
| | - Joel P Giblett
- Department of Interventional Cardiology, Papworth Hospital, Cambridge, United Kingdom.,Division of Cardiovascular Medicine, University of Cambridge, United Kingdom
| | - Paul A White
- Medical Physics and Clinical Engineering, Cambridge University Hospital NHS Foundation Trust, Cambridge, United Kingdom.,Postgraduate Medical Institute, Anglia Ruskin University, Chelmsford, United Kingdom
| | - Andrew Klein
- Department of Interventional Cardiology, Papworth Hospital, Cambridge, United Kingdom
| | - James Hampton-Til
- Postgraduate Medical Institute, Anglia Ruskin University, Chelmsford, United Kingdom
| | - Michael O'Sullivan
- Department of Interventional Cardiology, Papworth Hospital, Cambridge, United Kingdom
| | - Denise Braganza
- Department of Interventional Cardiology, Papworth Hospital, Cambridge, United Kingdom
| | - William R Davies
- Department of Interventional Cardiology, Papworth Hospital, Cambridge, United Kingdom
| | - Nick E J West
- Department of Interventional Cardiology, Papworth Hospital, Cambridge, United Kingdom
| | - Cameron G Densem
- Department of Interventional Cardiology, Papworth Hospital, Cambridge, United Kingdom
| | - Stephen P Hoole
- Department of Interventional Cardiology, Papworth Hospital, Cambridge, United Kingdom
| |
Collapse
|
24
|
Pérez del Villar C, Savvatis K, López B, Kasner M, Martinez-Legazpi P, Yotti R, González A, Díez J, Fernández-Avilés F, Tschöpe C, Bermejo J. Impact of acute hypertension transients on diastolic function in patients with heart failure with preserved ejection fraction. Cardiovasc Res 2017; 113:906-914. [DOI: 10.1093/cvr/cvx047] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 03/08/2017] [Indexed: 12/12/2022] Open
|
25
|
Ibrahim KS, El-Yazbi AF, El-Gowelli HM, El-Mas MM. Opposite Modulatory Effects of Selective and Non-Selective Cyclooxygenase Inhibition on Cardiovascular and Autonomic Consequences of Cyclosporine in Female Rats. Basic Clin Pharmacol Toxicol 2017; 120:571-581. [DOI: 10.1111/bcpt.12754] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/22/2016] [Indexed: 12/25/2022]
Affiliation(s)
- Karim S. Ibrahim
- Department of Pharmacology and Toxicology; Faculty of Pharmacy; Alexandria University; Alexandria Egypt
| | - Ahmed F. El-Yazbi
- Department of Pharmacology and Toxicology; Faculty of Pharmacy; Alexandria University; Alexandria Egypt
| | - Hanan M. El-Gowelli
- Department of Pharmacology and Toxicology; Faculty of Pharmacy; Alexandria University; Alexandria Egypt
| | - Mahmoud M. El-Mas
- Department of Pharmacology and Toxicology; Faculty of Pharmacy; Alexandria University; Alexandria Egypt
| |
Collapse
|
26
|
The inflammatory state provokes sexual dimorphism in left ventricular and electrocardiographic effects of chronic cyclosporine in rats. Sci Rep 2017; 7:42457. [PMID: 28211883 PMCID: PMC5304161 DOI: 10.1038/srep42457] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 01/11/2017] [Indexed: 01/22/2023] Open
Abstract
Although cardiotoxicity has been recognized as an adverse effect of cyclosporine A (CSA), no information exists regarding sex specificity of CSA cardiotoxicity. We tested the hypothesis that left ventricular (LV) and electrocardiographic (ECG) effects of CSA and related inflammatory/histopathological derangements are sex related. CSA reduced the LV slope of end-systolic pressure volume relationship and increased isovolumic relaxation constant. These effects were more pronounced in male compared to female rats, suggesting LV systolic and diastolic dysfunction. ECG recordings showed elevated ST segments and increased QTc and T peak trend intervals in CSA-treated male rats, markers of LV ischemia and arrhythmogenesis. In female rats, CSA delayed AV conduction, as reflected by prolonged PR interval. Other sex-related effects for CSA included (i) increased blood cholesterol, and reduced rates of rise and fall in LV pressure and nuclear factor kappa B and angiotensin receptors type 1 expressions in male rats, and (ii) increased LV adiponectin in females. Histopatholgically, CSA caused vascular congestion, blood extravasation, and pyknotic or even absent nuclei in both sexes. In conclusion, rats exhibit sex-independent susceptibility to negative LV and histopathological influences of CSA. These effects become more intensified in male rats, perhaps on account of aggravated ischemic and inflammatory milieus.
Collapse
|
27
|
Mizuno J, Mohri S, Yokoyama T, Otsuji M, Arita H, Hanaoka K. Temperature-dependent inotropic and lusitropic indices based on half-logistic time constants for four segmental phases in isovolumic left ventricular pressure–time curve in excised, cross-circulated canine heart. Can J Physiol Pharmacol 2017; 95:190-198. [DOI: 10.1139/cjpp-2015-0196] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Varying temperature affects cardiac systolic and diastolic function and the left ventricular (LV) pressure–time curve (PTC) waveform that includes information about LV inotropism and lusitropism. Our proposed half-logistic (h-L) time constants obtained by fitting using h-L functions for four segmental phases (Phases I–IV) in the isovolumic LV PTC are more useful indices for estimating LV inotropism and lusitropism during contraction and relaxation periods than the mono-exponential (m-E) time constants at normal temperature. In this study, we investigated whether the superiority of the goodness of h-L fits remained even at hypothermia and hyperthermia. Phases I–IV in the isovolumic LV PTCs in eight excised, cross-circulated canine hearts at 33, 36, and 38 °C were analyzed using h-L and m-E functions and the least-squares method. The h-L and m-E time constants for Phases I–IV significantly shortened with increasing temperature. Curve fitting using h-L functions was significantly better than that using m-E functions for Phases I–IV at all temperatures. Therefore, the superiority of the goodness of h-L fit vs. m-E fit remained at all temperatures. As LV inotropic and lusitropic indices, temperature-dependent h-L time constants could be more useful than m-E time constants for Phases I–IV.
Collapse
Affiliation(s)
- Ju Mizuno
- Department of Anesthesiology and Pain Medicine, Juntendo University Faculty of Medicine, Tokyo 113-8431, Japan
- Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, 700-8558, Japan
- Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, Fukuoka, 812-8582, Japan
- Department of Anesthesiology, Faculty of Medicine, The University of Tokyo, Tokyo, 113-8655, Japan
- Department of Anesthesiology and Pain Relief Center, JR Tokyo General Hospital, Tokyo, 151-8528, Japan
| | - Satoshi Mohri
- Department of Cardiovascular Physiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, 700-8558, Japan
- First Department of Physiology, Kawasaki Medical School, Kurashiki, 701-0192, Japan
| | - Takeshi Yokoyama
- Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, Fukuoka, 812-8582, Japan
- Department of Anesthesiology, Faculty of Medicine, The University of Tokyo, Tokyo, 113-8655, Japan
| | - Mikiya Otsuji
- Department of Anesthesiology, Faculty of Medicine, The University of Tokyo, Tokyo, 113-8655, Japan
| | - Hideko Arita
- Department of Anesthesiology and Pain Relief Center, JR Tokyo General Hospital, Tokyo, 151-8528, Japan
| | - Kazuo Hanaoka
- Department of Anesthesiology and Pain Relief Center, JR Tokyo General Hospital, Tokyo, 151-8528, Japan
| |
Collapse
|
28
|
Chowdhury SM, Goudar SP, Baker GH, Taylor CL, Shirali GS, Friedberg MK, Dragulescu A, Chessa KS, Mertens L. Speckle-Tracking Echocardiographic Measures of Right Ventricular Diastolic Function Correlate with Reference Standard Measures Before and After Preload Alteration in Children. Pediatr Cardiol 2017; 38:27-35. [PMID: 27655413 PMCID: PMC5288273 DOI: 10.1007/s00246-016-1479-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 09/15/2016] [Indexed: 01/19/2023]
Abstract
The accuracy of echocardiographic measures of right ventricular (RV) diastolic function has been sparsely studied. Our objective was to evaluate the correlation between echocardiographic and reference standard measures of RV diastolic function derived from micromanometer pressure analysis before and after preload alteration in children. Echocardiograms and micromanometer pressure analyses were prospectively performed before and after fluid bolus in children undergoing right heart catheterization. The isovolumic relaxation time constant (τ) and end-diastolic pressure (EDP) were measured. Conventional and speckle-tracking echocardiographic (STE) parameters of RV systolic and diastolic function were assessed. Normal saline bolus was given to increase RV EDP by 20 %. Twenty-eight studies were performed in 22 patients with congenital heart disease or postheart transplantation. Mean age was 8.7 ± 6.1 years. RV longitudinal early diastolic strain rate (EDSR) correlated with τ before (r = 0.57, p = 0.001) and after fluid bolus (r = 0.48, p = 0.008). No conventional echocardiographic measures correlated with τ both before and after fluid bolus. Multiple regression analysis revealed RV EDSR and LV circumferential EDSR as independent predictors of RV τ. There were no independent predictors of EDP. RV EDSR appears to correlate with the reference standard measure of early active ventricular relaxation in children at baseline and after changes in preload. Conventional echocardiographic measures of diastolic function were not predictive of diastolic function after preload alteration. Future studies should assess the prognostic significance of STE measures of diastolic function in this population.
Collapse
Affiliation(s)
- Shahryar M. Chowdhury
- Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina
| | - Suma P. Goudar
- The Ward Family Heart Center, Children’s Mercy Hospital, Kansas City, Missouri
| | - G. Hamilton Baker
- Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina
| | - Carolyn L. Taylor
- Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina
| | - Girish S. Shirali
- The Ward Family Heart Center, Children’s Mercy Hospital, Kansas City, Missouri
| | - Mark K. Friedberg
- Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Andreea Dragulescu
- Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Karen S. Chessa
- Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina
| | - Luc Mertens
- Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| |
Collapse
|
29
|
Gresham KS, Stelzer JE. The contributions of cardiac myosin binding protein C and troponin I phosphorylation to β-adrenergic enhancement of in vivo cardiac function. J Physiol 2016; 594:669-86. [PMID: 26635197 DOI: 10.1113/jp270959] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 11/30/2015] [Indexed: 01/12/2023] Open
Abstract
KEY POINTS β-adrenergic stimulation increases cardiac myosin binding protein C (MyBP-C) and troponin I phosphorylation to accelerate pressure development and relaxation in vivo, although their relative contributions remain unknown. Using a novel mouse model lacking protein kinase A-phosphorylatable troponin I (TnI) and MyBP-C, we examined in vivo haemodynamic function before and after infusion of the β-agonist dobutamine. Mice expressing phospho-ablated MyBP-C displayed cardiac hypertrophy and prevented full acceleration of pressure development and relaxation in response to dobutamine, whereas expression of phosphor-ablated TnI alone had little effect on the acceleration of contractile function in response to dobutamine. Our data demonstrate that MyBP-C phosphorylation is the principal mediator of the contractile response to increased β-agonist stimulation in vivo. These results help us understand why MyBP-C dephosphorylation in the failing heart contributes to contractile dysfunction and decreased adrenergic reserve in response to acute stress. β-adrenergic stimulation plays a critical role in accelerating ventricular contraction and speeding relaxation to match cardiac output to changing circulatory demands. Two key myofilaments proteins, troponin I (TnI) and myosin binding protein-C (MyBP-C), are phosphorylated following β-adrenergic stimulation; however, their relative contributions to the enhancement of in vivo cardiac contractility are unknown. To examine the roles of TnI and MyBP-C phosphorylation in β-adrenergic-mediated enhancement of cardiac function, transgenic (TG) mice expressing non-phosphorylatable TnI protein kinase A (PKA) residues (i.e. serine to alanine substitution at Ser23/24; TnI(PKA-)) were bred with mice expressing non-phosphorylatable MyBP-C PKA residues (i.e. serine to alanine substitution at Ser273, Ser282 and Ser302; MyBPC(PKA-)) to generate a novel mouse model expressing non-phosphorylatable PKA residues in TnI and MyBP-C (DBL(PKA-)). MyBP-C dephosphorylation produced cardiac hypertrophy and increased wall thickness in MyBPC(PKA-) and DBL(PKA-) mice, and in vivo echocardiography and pressure-volume catheterization studies revealed impaired systolic function and prolonged diastolic relaxation compared to wild-type and TnI(PKA-) mice. Infusion of the β-agonist dobutamine resulted in accelerated rates of pressure development and relaxation in all mice; however, MyBPC(PKA-) and DBL(PKA-) mice displayed a blunted contractile response compared to wild-type and TnI(PKA-) mice. Furthermore, unanaesthesized MyBPC(PKA-) and DBL(PKA-) mice displayed depressed maximum systolic pressure in response to dobutamine as measured using implantable telemetry devices. Taken together, our data show that MyBP-C phosphorylation is a critical modulator of the in vivo acceleration of pressure development and relaxation as a result of enhanced β-adrenergic stimulation, and reduced MyBP-C phosphorylation may underlie depressed adrenergic reserve in heart failure.
Collapse
Affiliation(s)
- Kenneth S Gresham
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Julian E Stelzer
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| |
Collapse
|
30
|
Ventricular-vascular dynamics in pediatric patients with heart failure and preserved ejection fraction. Int J Cardiol 2016; 225:306-312. [PMID: 27744267 DOI: 10.1016/j.ijcard.2016.09.118] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 09/25/2016] [Accepted: 09/29/2016] [Indexed: 11/20/2022]
Abstract
OBJECTIVE The details of the ventricular-vascular dynamics of heart failure with preserved ejection fraction (HFpEF) in children remain poorly understood. We tested the hypothesis that pediatric HFpEF patients have ventricular systolic, diastolic, and arterial stiffening at rest as well as impaired reserve function associated with coronary supply/demand imbalance. METHODS We studied the ventricular pressure-area relationship in 22 pediatric HFpEF patients and 22 control subjects before and after dobutamine infusion and during abdominal compression. Coronary supply/demand balance was assessed by subendocardial viability ratio (SEVR) calculated from the aortic pressure waveform. RESULTS Compared with controls, the HFpEF patients had significantly higher end-systolic (Ees) and arterial (Ea) elastance. Increased ventricular diastolic stiffness also occurred in the HFpEF patients, resulting in modest elevation of end-diastolic pressure (EDP) at rest (13.6±4.3 vs. 7.3±2.3mmHg, P<0.0001). The difference in EDP became more evident with a preload increase through abdominal compression, indicating a limited diastolic reserve in HFpEF patients (EDP changes; 11.3±6.2 for HFpEF vs. 3.4±0.6mmHg for controls, P=0.016). The HFpEF patients exhibited impaired beta-adrenergic reserve in ventricular contractility and ventricular-arterial coupling in response to dobutamine infusion. SEVR was significantly lower in the HFpEF (0.64±0.11) than in the control (0.79±0.07, P<0.0001) and was significantly correlated with LV diastolic stiffness and dobutamine-induced changes in ventricular contractility. CONCLUSIONS HFpEF in children involves higher ventricular-arterial stiffness at rest as well as impaired systolic and diastolic reserve, which closely correlate with impaired coronary supply/demand balance.
Collapse
|
31
|
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.
Collapse
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,
| | | | | | | |
Collapse
|
32
|
Chung CS, Shmuylovich L, Kovács SJ. What global diastolic function is, what it is not, and how to measure it. Am J Physiol Heart Circ Physiol 2015; 309:H1392-406. [DOI: 10.1152/ajpheart.00436.2015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 08/17/2015] [Indexed: 12/17/2022]
Abstract
Despite Leonardo da Vinci's observation (circa 1511) that “the atria or filling chambers contract together while the pumping chambers or ventricles are relaxing and vice versa,” the dynamics of four-chamber heart function, and of diastolic function (DF) in particular, are not generally appreciated. We view DF from a global perspective, while characterizing it in terms of causality and clinical relevance. Our models derive from the insight that global DF is ultimately a result of forces generated by elastic recoil, modulated by cross-bridge relaxation, and load. The interaction between recoil and relaxation results in physical wall motion that generates pressure gradients that drive fluid flow, while epicardial wall motion is constrained by the pericardial sac. Traditional DF indexes (τ, E/E′, etc.) are not derived from causal mechanisms and are interpreted as approximating either stiffness or relaxation, but not both, thereby limiting the accuracy of DF quantification. Our derived kinematic models of isovolumic relaxation and suction-initiated filling are extensively validated, quantify the balance between stiffness and relaxation, and provide novel mechanistic physiological insight. For example, causality-based modeling provides load-independent indexes of DF and reveals that both stiffness and relaxation modify traditional DF indexes. The method has revealed that the in vivo left ventricular equilibrium volume occurs at diastasis, predicted novel relationships between filling and wall motion, and quantified causal relationships between ventricular and atrial function. In summary, by using governing physiological principles as a guide, we define what global DF is, what it is not, and how to measure it.
Collapse
Affiliation(s)
- Charles S. Chung
- Department of Physiology and Center for Muscle Biology, University of Kentucky, Lexington, Kentucky, and Department of Physiology, Wayne State University, Detroit, Michigan; and
| | - Leonid Shmuylovich
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Sándor J. Kovács
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| |
Collapse
|
33
|
Re: Chung et al.’s Letter to the Editor in response to: Early detection of abnormal left ventricular relaxation in acute myocardial ischemia with a quadratic model. Med Eng Phys 2014;36(September (9)):1101–5 by Morimont et al. Med Eng Phys 2015; 37:827. [DOI: 10.1016/j.medengphy.2015.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 05/11/2015] [Accepted: 05/11/2015] [Indexed: 11/21/2022]
|
34
|
Schwarzl M, Alogna A, Zirngast B, Steendijk P, Verderber J, Zweiker D, Huber S, Maechler H, Pieske BM, Post H. Mild hypothermia induces incomplete left ventricular relaxation despite spontaneous bradycardia in pigs. Acta Physiol (Oxf) 2015; 213:653-63. [PMID: 25515791 DOI: 10.1111/apha.12439] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 08/11/2014] [Accepted: 12/10/2014] [Indexed: 01/08/2023]
Abstract
AIM Mild hypothermia (MH) decreases left ventricular (LV) end-diastolic capacitance. We sought to clarify whether this results from incomplete relaxation. METHODS Ten anaesthetized pigs were cooled from normothermia (NT, 38 °C) to MH (33 °C). LV end-diastolic pressure (LVPed), volume (LVVed) and pressure-volume relationships (EDPVRs) were determined during stepwise right atrial pacing. LV capacitance (i.e. LVVed at LVPed of 10 mmHg, LV VPed10) was derived from the EDPVR. Pacing-induced changes of diastolic indices (LVPed, LVVed and LV VPed10) were analysed as a function of (i) heart rate and (ii) the ratio between diastolic time interval (t-dia) and LV isovolumic relaxation constant τ, which was calculated using a logistic fit (τL ) and monoexponential fit with zero asymptote (τZ ) and nonzero asymptote (τNZ ). RESULTS Mild hypothermia decreased heart rate (85 ± 4 to 68 ± 3 bpm), increased τL (22 ± 1 to 57 ± 4 ms), τZ (26 ± 2 to 56 ± 5 ms) and τNZ (41 ± 1 to 96 ± 5 ms), decreased t-dia/τ ratios, and shifted the EDPVR leftwards compared to NT (all P < 0.05). During NT, pacing at ≥140 bpm shifted the EDPVR progressively leftwards. During MH, relationships between diastolic indices and heart rate were shifted towards lower heart rates compared to NT. However, relationships between diastolic indices and t-dia/τ during NT and MH were superimposable. CONCLUSION We conclude that the loss of LV end-diastolic capacitance during MH can be explained at least in part by slowed LV relaxation. MH thereby is an example of incomplete LV relaxation at a spontaneous low heart rate. Caution may be advised, when heart rate is increased in patients treated with MH.
Collapse
Affiliation(s)
- M. Schwarzl
- Department of General and Interventional Cardiology; University Heart Center Hamburg-Eppendorf; Hamburg Germany
| | - A. Alogna
- Department of Cardiology; Medical University of Graz; Graz Austria
| | - B. Zirngast
- Department of Cardiothoracic Surgery; Medical University of Graz; Graz Austria
| | - P. Steendijk
- Department of Cardiology; Leiden University Medical Center; Leiden the Netherlands
| | - J. Verderber
- Department of Cardiology; Medical University of Graz; Graz Austria
| | - D. Zweiker
- Department of Cardiology; Medical University of Graz; Graz Austria
| | - S. Huber
- Department of Cardiothoracic Surgery; Medical University of Graz; Graz Austria
| | - H. Maechler
- Department of Cardiothoracic Surgery; Medical University of Graz; Graz Austria
| | - B. M. Pieske
- Department of Cardiology; Charit e-Universitaetsmedizin Berlin; Campus Virchow-Klinikum; Berlin Germany
| | - H. Post
- Department of Cardiology; Charit e-Universitaetsmedizin Berlin; Campus Virchow-Klinikum; Berlin Germany
| |
Collapse
|
35
|
Pérez Del Villar C, Bermejo J, Rodríguez-Pérez D, Martínez-Legazpi P, Benito Y, Antoranz JC, Desco MM, Ortuño JE, Barrio A, Mombiela T, Yotti R, Ledesma-Carbayo MJ, Del Álamo JC, Fernández-Avilés F. The role of elastic restoring forces in right-ventricular filling. Cardiovasc Res 2015; 107:45-55. [PMID: 25691537 DOI: 10.1093/cvr/cvv047] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 02/08/2015] [Indexed: 11/14/2022] Open
Abstract
AIMS The physiological determinants of RV diastolic function remain poorly understood. We aimed to quantify the contribution of elastic recoil to RV filling and determine its sensitivity to interventricular interaction. METHODS AND RESULTS High-fidelity pressure-volume loops and simultaneous 3-dimensional ultrasound sequences were obtained in 13 pigs undergoing inotropic modulation, volume overload, and acute pressure overload induced by endotoxin infusion. Using a validated method, we isolated elastic restoring forces from ongoing relaxation using conventional pressure-volume data. The RV contracted below the equilibrium volume in >75% of the data sets. Consequently, elastic recoil generated strong sub-atmospheric passive pressure at the onset of diastole [-3 (-4 to -2) mmHg at baseline]. Stronger restoring suction pressure was related to a shorter isovolumic relaxation period, a higher rapid filling fraction, and lower atrial pressures (all P < 0.05). Restoring forces were mostly determined by the position of operating volumes around the equilibrium volume. By this mechanism, the negative inotropic effect of beta-blockade reduced and sometimes abolished restoring forces. During acute pressure overload, restoring forces initially decreased, but recovered at advanced stages. This biphasic response was related to alterations of septal curvature induced by changes in the diastolic LV-RV pressure balance. The constant of elastic recoil was closely related to the constant of passive stiffness (R = 0.69). CONCLUSION The RV works as a suction pump, exploiting contraction energy to facilitate filling by means of strong elastic recoil. Restoring forces are influenced by the inotropic state and RV conformational changes mediated by direct ventricular interdependence.
Collapse
Affiliation(s)
- Candelas Pérez Del Villar
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
| | - Javier Bermejo
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
| | - Daniel Rodríguez-Pérez
- Department of Mathematical Physics and Fluids, Facultad de Ciencias, Universidad Nacional de Educación a Distancia, Madrid, Spain
| | - Pablo Martínez-Legazpi
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain Mechanical and Aerospace Engineering Department, University of California San Diego, La Jolla, CA, USA
| | - Yolanda Benito
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
| | - J Carlos Antoranz
- Department of Mathematical Physics and Fluids, Facultad de Ciencias, Universidad Nacional de Educación a Distancia, Madrid, Spain
| | - M Mar Desco
- Department of Mathematical Physics and Fluids, Facultad de Ciencias, Universidad Nacional de Educación a Distancia, Madrid, Spain
| | - Juan E Ortuño
- Biomedical Image Technologies, Universidad Politécnica de Madrid & CIBER-BBN, Madrid, Spain
| | - Alicia Barrio
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
| | - Teresa Mombiela
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
| | - Raquel Yotti
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
| | | | - Juan C Del Álamo
- Mechanical and Aerospace Engineering Department, University of California San Diego, La Jolla, CA, USA Institute for Engineering in Medicine, University of California San Diego, La Jolla, CA, USA
| | - Francisco Fernández-Avilés
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
| |
Collapse
|
36
|
Diakos NA, Pozios I, Katsaros L, Vakrou S, Sventzouri S, Michelinakis N, Tseliou E, Bonios M, Malliaras K, Papalois A, Anastasiou-Nana M, Terrovitis JV. Afterload-induced left ventricular diastolic dysfunction during myocardial ischaemia and reperfusion. Exp Physiol 2015; 100:288-301. [DOI: 10.1113/expphysiol.2014.082131] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/12/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Nikolaos A. Diakos
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | - Iraklis Pozios
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | - Lampros Katsaros
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | - Styliani Vakrou
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | - Stefania Sventzouri
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | - Nikolaos Michelinakis
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | - Eleni Tseliou
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | - Michael Bonios
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | | | - Apostolos Papalois
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | - Maria Anastasiou-Nana
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| | - John V. Terrovitis
- The 3rd Department of Cardiology; University of Athens; ‘Laiko’ Hospital; Athens Greece
| |
Collapse
|
37
|
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]
|
38
|
Mossahebi S, Kovács SJ. The isovolumic relaxation to early rapid filling relation: kinematic model based prediction with in vivo validation. Physiol Rep 2014; 2:e00258. [PMID: 24760512 PMCID: PMC4002238 DOI: 10.1002/phy2.258] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Although catheterization is the gold standard, Doppler echocardiography is the preferred diastolic function (DF) characterization method. The physiology of diastole requires continuity of left ventricular pressure (LVP)‐generating forces before and after mitral valve opening (MVO). Correlations between isovolumic relaxation (IVR) indexes such as tau (time‐constant of IVR) and noninvasive, Doppler E‐wave‐derived metrics, such as peak A‐V gradient or deceleration time (DT), have been established. However, what has been missing is the model‐predicted causal link that connects isovolumic relaxation (IVR) to suction‐initiated filling (E‐wave). The physiology requires that model‐predicted terminal force of IVR (FtIVR) and model‐predicted initial force of early rapid filling (Fi E‐wave) after MVO be correlated. For validation, simultaneous (conductance catheter) P‐V and E‐wave data from 20 subjects (mean age 57 years, 13 men) having normal LV ejection fraction (LVEF>50%) and a physiologic range of LV end‐diastolic pressure (LVEDP) were analyzed. For each cardiac cycle, the previously validated kinematic (Chung) model for isovolumic pressure decay and the Parametrized Diastolic Filling (PDF) kinematic model for the subsequent E‐wave provided FtIVR and Fi E‐wave respectively. For all 20 subjects (15 beats/subject, 308 beats), linear regression yielded FtIVR = α Fi E‐wave + b (R = 0.80), where α = 1.62 and b = 1.32. We conclude that model‐based analysis of IVR and of the E‐wave elucidates DF mechanisms common to both. The observed in vivo relationship provides novel insight into diastole itself and the model‐based causal mechanistic relationship that couples IVR to early rapid filling.
Collapse
Affiliation(s)
- Sina Mossahebi
- Department of Physics, College of Arts and Sciences, Washington University in St. Louis, St. Louis, Missouri
| | | |
Collapse
|
39
|
Assessment of ventricular relaxation and stiffness using early diastolic mitral annular and inflow velocities in pediatric patients with heart disease. Heart Vessels 2013; 29:825-33. [DOI: 10.1007/s00380-013-0422-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 09/27/2013] [Indexed: 01/16/2023]
|
40
|
Hillestad V, Kramer F, Golz S, Knorr A, Andersson KB, Christensen G. Long-term levosimendan treatment improves systolic function and myocardial relaxation in mice with cardiomyocyte-specific disruption of the Serca2 gene. J Appl Physiol (1985) 2013; 115:1572-80. [PMID: 24072410 DOI: 10.1152/japplphysiol.01044.2012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In human heart failure (HF), reduced cardiac function has, at least partly, been ascribed to altered calcium homeostasis in cardiomyocytes. The effects of the calcium sensitizer levosimendan on diastolic dysfunction caused by reduced removal of calcium from cytosol in early diastole are not well known. In this study, we investigated the effect of long-term levosimendan treatment in a murine model of HF where the sarco(endo)plasmatic reticulum ATPase (Serca) gene is specifically disrupted in the cardiomyocytes, leading to reduced removal of cytosolic calcium. After induction of Serca2 gene disruption, these mice develop marked diastolic dysfunction as well as impaired contractility. SERCA2 knockout (SERCA2KO) mice were treated with levosimendan or vehicle from the time of KO induction. At the 7-wk end point, cardiac function was assessed by echocardiography and pressure measurements. Vehicle-treated SERCA2KO mice showed significantly diminished left-ventricular (LV) contractility, as shown by decreased ejection fraction, stroke volume, and cardiac output. LV pressure measurements revealed a marked increase in the time constant (τ) of isovolumetric pressure decay, showing impaired relaxation. Levosimendan treatment significantly improved all three systolic parameters. Moreover, a significant reduction in τ toward normalization indicated improved relaxation. Gene-expression analysis, however, revealed an increase in genes related to production of the ECM in animals treated with levosimendan. In conclusion, long-term levosimendan treatment improves both contractility and relaxation in a heart-failure model with marked diastolic dysfunction due to reduced calcium transients. However, altered gene expression related to fibrosis was observed.
Collapse
Affiliation(s)
- Vigdis Hillestad
- Institute for Experimental Medical Research, Oslo University Hospital Ullevål and University of Oslo, Oslo, Norway
| | | | | | | | | | | |
Collapse
|
41
|
Ghosh E, Kovács SJ. The quest for load-independent left ventricular chamber properties: Exploring the normalized pressure phase plane. Physiol Rep 2013; 1:e00043. [PMID: 24303128 PMCID: PMC3834999 DOI: 10.1002/phy2.43] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 07/03/2013] [Accepted: 07/04/2013] [Indexed: 12/05/2022] Open
Abstract
The pressure phase plane (PPP), defined by dP(t)/dt versus P(t) coordinates has revealed novel physiologic relationships not readily obtainable from conventional, time domain analysis of left ventricular pressure (LVP). We extend the methodology by introducing the normalized pressure phase plane (nPPP), defined by 0 ≤ P ≤ 1 and -1 ≤ dP/dt ≤ +1. Normalization eliminates load-dependent effects facilitating comparison of conserved features of nPPP loops. Hence, insight into load-invariant systolic and diastolic chamber properties and their coupling to load can be obtained. To demonstrate utility, high-fidelity P(t) data from 14 subjects (4234 beats) was analyzed. PNR, the nPPP (dimensionless) pressure, where -dP/dtpeak occurs, was 0.61 and had limited variance (7%). The relative load independence of PNR was corroborated by comparison of PPP and nPPP features of normal sinus rhythm (NSR) and (ejecting and nonejecting) premature ventricular contraction (PVC) beats. PVCs had lower P(t)max and lower peak negative and positive dP(t)/dt values versus NSR beats. In the nPPP, +dP/dtpeak occurred at higher (dimensionless) P in PVC beats than in regular beats (0.44 in NSR vs. 0.48 in PVC). However, PNR for PVC versus NSR remained unaltered (PNR = 0.64; P > 0.05). Possible mechanistic explanation includes a (near) load-independent (constant) ratio of maximum cross-bridge uncoupling rate to instantaneous wall stress. Hence, nPPP analysis reveals LV properties obscured by load and by conventional temporal P(t) and dP(t)/dt analysis. nPPP identifies chamber properties deserving molecular and cellular physiologic explanation.
Collapse
Affiliation(s)
- Erina Ghosh
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Department of Internal Medicine, Washington University School of Medicine St. Louis, Missouri ; Department of Biomedical Engineering, School of Engineering and Applied Science, Washington University in St. Louis St. Louis, Missouri
| | | |
Collapse
|
42
|
Bermejo J, Yotti R, Pérez del Villar C, del Álamo JC, Rodríguez-Pérez D, Martínez-Legazpi P, Benito Y, Antoranz JC, Desco MM, González-Mansilla A, Barrio A, Elízaga J, Fernández-Avilés F. Diastolic chamber properties of the left ventricle assessed by global fitting of pressure-volume data: improving the gold standard of diastolic function. J Appl Physiol (1985) 2013; 115:556-68. [PMID: 23743396 DOI: 10.1152/japplphysiol.00363.2013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In cardiovascular research, relaxation and stiffness are calculated from pressure-volume (PV) curves by separately fitting the data during the isovolumic and end-diastolic phases (end-diastolic PV relationship), respectively. This method is limited because it assumes uncoupled active and passive properties during these phases, it penalizes statistical power, and it cannot account for elastic restoring forces. We aimed to improve this analysis by implementing a method based on global optimization of all PV diastolic data. In 1,000 Monte Carlo experiments, the optimization algorithm recovered entered parameters of diastolic properties below and above the equilibrium volume (intraclass correlation coefficients = 0.99). Inotropic modulation experiments in 26 pigs modified passive pressure generated by restoring forces due to changes in the operative and/or equilibrium volumes. Volume overload and coronary microembolization caused incomplete relaxation at end diastole (active pressure > 0.5 mmHg), rendering the end-diastolic PV relationship method ill-posed. In 28 patients undergoing PV cardiac catheterization, the new algorithm reduced the confidence intervals of stiffness parameters by one-fifth. The Jacobian matrix allowed visualizing the contribution of each property to instantaneous diastolic pressure on a per-patient basis. The algorithm allowed estimating stiffness from single-beat PV data (derivative of left ventricular pressure with respect to volume at end-diastolic volume intraclass correlation coefficient = 0.65, error = 0.07 ± 0.24 mmHg/ml). Thus, in clinical and preclinical research, global optimization algorithms provide the most complete, accurate, and reproducible assessment of global left ventricular diastolic chamber properties from PV data. Using global optimization, we were able to fully uncouple relaxation and passive PV curves for the first time in the intact heart.
Collapse
Affiliation(s)
- Javier Bermejo
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, and the Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Mitsuyama S, Takeshita D, Obata K, Zhang GX, Takaki M. Left ventricular mechanical and energetic changes in long-term isoproterenol-induced hypertrophied hearts of SERCA2a transgenic rats. J Mol Cell Cardiol 2013; 59:95-106. [DOI: 10.1016/j.yjmcc.2013.02.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 02/17/2013] [Accepted: 02/21/2013] [Indexed: 12/31/2022]
|
44
|
Yang B, Larson DF, Ranger-Moore J. Biphasic change of tau (τ) in mice as arterial load acutely increased with phenylephrine injection. PLoS One 2013; 8:e60580. [PMID: 23593252 PMCID: PMC3620408 DOI: 10.1371/journal.pone.0060580] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 02/28/2013] [Indexed: 12/03/2022] Open
Abstract
Background Diastolic dysfunction is the hemodynamic hallmark of hypertensive heart disease. Tau (τ) has been used to describe left ventricle relaxation. The relationship between τ and afterload has been controversial. Our goal was to demonstrate this relationship in mice, because genetically-modified mouse models have been used extensively for studies in cardiovascular diseases. Methods Increased arterial load was produced by phenylephrine administration (50 µg/kg iv) (n = 10). A series of pressure-volume loops was recorded with a Millar conductance catheter in vivo as the left ventricle pressure reached the maximum. The arterial load was expressed as Ea (effective arterial elastance). Tau values were computed using three mathematical methods: τWeiss, τGlantz, and τLogistic. Results A correlation plot between τ and Ea showed a biphasic relationship a flat phase I and an inclined phase II. The existence of an inflection point was proved mathematically with biphasic linear regression. Pressure-volume area (PVA), a parameter linearly related to myocardial O2 consumption (MVO2), was found to be directly proportional to Ea. The plot of τ versus PVA was also biphasic. Conclusion We concluded that a small increase of the arterial load by phenylephrine increased PVA (index of MVO2) but had little effect on τ. However, after an inflection point, further increase of arterial load and PVA resulted in the linear increase of τ.
Collapse
Affiliation(s)
- Bo Yang
- Department of Cardiac Surgery, Cardiovascular Center, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
| | - Douglas F. Larson
- Sarver Heart Center and the Department of Medical Pharmacology, College of Medicine, The University of Arizona, Tucson, Arizona, United States of America
| | - James Ranger-Moore
- Division of Epidemiology and Biostatistics, Mel and Enid Zuckerman College of Public Health, The University of Arizona, Tucson, Arizona, United States of America
| |
Collapse
|
45
|
Herberg U, Gatzweiler E, Breuer T, Breuer J. Ventricular pressure–volume loops obtained by 3D real-time echocardiography and mini pressure wire—a feasibility study. Clin Res Cardiol 2013; 102:427-38. [DOI: 10.1007/s00392-013-0548-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 01/28/2013] [Indexed: 01/01/2023]
|
46
|
Zhang GX, Obata K, Takeshita D, Mitsuyama S, Nakashima T, Kikuta A, Hirabayashi M, Tomita K, Vetter R, Dillmann WH, Takaki M. Evaluation of left ventricular mechanical work and energetics of normal hearts in SERCA2a transgenic rats. J Physiol Sci 2012; 62:221-31. [PMID: 22383047 PMCID: PMC10717940 DOI: 10.1007/s12576-012-0200-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 02/09/2012] [Indexed: 10/28/2022]
Abstract
Cardiac sarcoplasmic reticulum (SR) Ca(2+)-ATPase (SERCA2a) is responsible for most of the Ca(2+) removal during diastole and a larger Ca(2+) handling energy consumer in excitation-contraction (E-C) coupling. To understand the cardiac performance under long-term SERCA2a overexpression conditions, we established SERCA2a transgenic (TG) Wistar rats to analyze cardiac mechanical work and energetics in normal hearts during pacing at 300 beats/min. SERCA2a protein expression was increased in TGI and TGII rats (F2 and F3 of the same father and different mothers). Mean left ventricular (LV) end-systolic pressure (ESP) and systolic pressure-volume area (PVA; a total mechanical energy per beat) at midrange LV volume (mLVV) were significantly larger in TGI rats and were unchanged in TGII rats, compared to those in non-TG [wildtype (WT)] littermates. Mean myocardial oxygen consumption per minute for E-C coupling was significantly increased, and the mean slope of myocardial oxygen consumption per beat (VO(2))-PVA (systolic PVA) linear relation was smaller, but the overall O(2) cost of LV contractility for Ca(2+) is unchanged in all TG rats. Mean Ca(2+) concentration exerting maximal ESP(mLVV) in TGII rats was significantly higher than that in WT rats. The Ca(2+) overloading protocol did not elicit mitochondrial swelling in TGII rats. Tolerance to higher Ca(2+) concentrations may support the possibility for enhanced SERCA2a activity in TGII rats. In conclusion, long-term SERCA2a overexpression enhanced or maintained LV mechanics, improved contractile efficiency under higher energy expenditure for Ca(2+) handling, and improved Ca(2+) tolerance, but it did not change the overall O(2) cost of LV contractility for Ca(2+) in normal hearts of TG rats.
Collapse
Affiliation(s)
- Guo-Xing Zhang
- Department of Physiology II, Nara Medical University School of Medicine, 840 Shijo-cho, Kashihara, Nara 634-8521 Japan
- Department of Physiology, Medical College of Soochow University, Dushu Lake Campus, Suzhou Industrial Park, Suzhou, 215123 People’s Republic of China
| | - Koji Obata
- Department of Physiology II, Nara Medical University School of Medicine, 840 Shijo-cho, Kashihara, Nara 634-8521 Japan
| | - Daisuke Takeshita
- Department of Physiology II, Nara Medical University School of Medicine, 840 Shijo-cho, Kashihara, Nara 634-8521 Japan
| | - Shinichi Mitsuyama
- Department of Physiology II, Nara Medical University School of Medicine, 840 Shijo-cho, Kashihara, Nara 634-8521 Japan
| | - Tamiji Nakashima
- Department of Anatomy, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, 807-8555 Japan
| | - Akio Kikuta
- Department of Anatomy, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, 807-8555 Japan
| | - Masumi Hirabayashi
- National Institute for Physiological Sciences, Okazaki, Aichi 444-8787 Japan
| | - Koichi Tomita
- National Institute for Physiological Sciences, Okazaki, Aichi 444-8787 Japan
| | - Roland Vetter
- Institut für Klinische Pharmakologie und Toxikologie, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Hufelandweg 9, 10117 Berlin, Germany
| | | | - Miyako Takaki
- Department of Physiology II, Nara Medical University School of Medicine, 840 Shijo-cho, Kashihara, Nara 634-8521 Japan
| |
Collapse
|
47
|
Ghosh E, Kovács SJ. Spatio-temporal attributes of left ventricular pressure decay rate during isovolumic relaxation. Am J Physiol Heart Circ Physiol 2012; 302:H1094-101. [DOI: 10.1152/ajpheart.00990.2011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Global left ventricular (LV) isovolumic relaxation rate has been characterized: 1) via the time constant of isovolumic relaxation τ or 2) via the logistic time constant τ L. An alternate kinematic method, characterizes isovolumic relaxation (IVR) in accordance with Newton's Second Law. The model's parameters, stiffness Ek, and damping/relaxation μ result from best fit of model-predicted pressure to in vivo data. All three models (exponential, logistic, and kinematic) characterize global relaxation in terms of pressure decay rates. However, IVR is inhomogeneous and anisotropic. Apical and basal LV wall segments untwist at different times and rates, and transmural strain and strain rates differ due to the helically variable pitch of myocytes and sheets. Accordingly, we hypothesized that the exponential model (τ) or kinematic model (μ and Ek) parameters will elucidate the spatiotemporal variation of IVR rate. Left ventricular pressures in 20 subjects were recorded using a high-fidelity, multipressure transducer (3 cm apart) catheter. Simultaneous, dual-channel pressure data was plotted in the pressure phase-plane (dP/d t vs. P) and τ, μ, and Ek were computed in 1631 beats (average: 82 beats per subject). Tau differed significantly between the two channels ( P < 0.05) in 16 of 20 subjects, whereas μ and Ek differed significantly ( P < 0.05) in all 20 subjects. These results show that quantifying the relaxation rate from data recorded at a single location has limitations. Moreover, kinematic model based analysis allows characterization of restoring (recoil) forces and resistive (crossbridge uncoupling) forces during IVR and their spatio-temporal dependence, thereby elucidating the relative roles of stiffness vs. relaxation as IVR rate determinants.
Collapse
Affiliation(s)
- Erina Ghosh
- Department of Biomedical Engineering, School of Engineering and Applied Science, Washington University, St. Louis, Missouri
| | - Sándor J. Kovács
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Department of Internal Medicine, School of Medicine; and
- Department of Biomedical Engineering, School of Engineering and Applied Science, Washington University, St. Louis, Missouri
| |
Collapse
|
48
|
Diastolic tolerance to systolic pressures closely reflects systolic performance in patients with coronary heart disease. Basic Res Cardiol 2012; 107:251. [PMID: 22311733 DOI: 10.1007/s00395-012-0251-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 01/05/2012] [Accepted: 01/26/2012] [Indexed: 12/18/2022]
Abstract
In animal experiments, elevating systolic pressures induces diastolic dysfunction and may contribute to congestion, a finding not yet translated to humans. Coronary surgery patients (63 ± 8 years) were studied with left ventricular (LV) pressure (n = 17) or pressure-volume (n = 3) catheters, immediately before cardiopulmonary bypass. Single-beat graded pressure elevations were induced by clamping the ascending aorta. Protocol was repeated after volume loading (n = 7). Consecutive patients with a wide range of systolic function were included. Peak isovolumetric LV pressure (LVP(iso)) ranged from 113 to 261 mmHg. With preserved systolic function, LVP elevations neither delayed relaxation nor increased filling pressures. With decreasing systolic function, diastolic tolerance to afterload progressively disappeared: relaxation slowed and filling pressures increased (diastolic dysfunction). In severely depressed systolic function, filling pressures increased even with minor LVP elevations, suggesting baseline load-dependent elevation of diastolic pressures. The magnitude of filling pressure elevation induced in isovolumetric heartbeats was closely and inversely related to systolic performance, evaluated by LVP(iso) (r = -0.96), and directly related to changes in the time constant of relaxation τ (r = 0.95). The maximum tolerated systolic LVP (without diastolic dysfunction) was similarly correlated with LVP(iso) (r = 0.99). Volume loading itself accelerated relaxation, but augmented afterload-induced upward shift of filling pressures (7.9 ± 3.7 vs. 3.0 ± 1.5; P < 0.01). The normal human response to even markedly increased systolic pressures is no slowing of relaxation and preservation of normal filling pressures. When cardiac function deteriorates, the LV becomes less tolerant, responding with slowed relaxation and increased filling pressures. This increase is exacerbated by volume loading.
Collapse
|
49
|
Moscato F, Granegger M, Naiyanetr P, Wieselthaler G, Schima H. Evaluation of left ventricular relaxation in rotary blood pump recipients using the pump flow waveform: a simulation study. Artif Organs 2011; 36:470-8. [PMID: 22171892 DOI: 10.1111/j.1525-1594.2011.01392.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In heart failure, diastolic dysfunction is responsible for about 50% of the cases, with higher prevalence in women and elderly persons and contributing similarly to mortality as systolic dysfunction. Whereas the cardiac systolic diagnostics in ventricular assist device patients from pump parameters have been investigated by several groups, the diastolic behavior has been barely discussed. This study focuses on the determination of ventricular relaxation during early diastole in rotary blood pump (RBP) recipients. In conventional cardiology, relaxation is usually evaluated by the minimum rate and the time constant of left ventricular pressure decrease, dP/dt(min) and τ(P) . Two new analogous indices derived from the pump flow waveform were investigated in this study: the minimum rate and the time constant of pump flow decrease, dQ/dt(min) and τ(Q) . The correspondence between the indices was investigated in a numerical simulation of the assisted circulation for different ventricular relaxation states (τ(P) ranging from 24 to 68 ms) and two RBP models characterized by linear and nonlinear pressure-flow characteristics. dQ/dt(min) and τ(Q) always correlated with the dP/dt(min) and τ(P) , respectively (r>0.97). These relationships were influenced by the nonlinear pump characteristics during partial support and by the pump speed during full support. To minimize these influences, simulation results suggest the evaluation of dQ/dt(min) and τ(Q) at a pump speed that corresponds to the borderline between partial and full support. In conclusion, at least in simulation, relaxation can be derived from pump data. This noninvasively accessible information could contribute to a continuous estimation of the remaining cardiac function and its eventual recovery.
Collapse
Affiliation(s)
- Francesco Moscato
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, AKH-4L, Waehringer Guertel18–20, 1090 Vienna, Austria.
| | | | | | | | | |
Collapse
|
50
|
Cingolani OH, Kass DA. Pressure-volume relation analysis of mouse ventricular function. Am J Physiol Heart Circ Physiol 2011; 301:H2198-206. [PMID: 21926344 DOI: 10.1152/ajpheart.00781.2011] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nearly 40 years ago, the Sagawa laboratory spawned a renaissance in the use of instantaneous ventricular pressure-volume (P-V) relations to assess cardiac function. Since then, this analysis has taken hold as the most comprehensive way to quantify ventricular chamber function and energetics and cardiovascular interactions. First studied in large mammalian hearts and later in humans employing a catheter-based method, P-V analysis was translated to small rodents in the late 1990s by the Kass laboratory. Over the past decade, this approach has become a gold standard for comprehensive examination of in vivo cardiac function in mice, facilitating a new era of molecular cardiac physiology. The catheter-based method remains the most widely used approach in mice. In this brief review, we discuss this instrumentation, the theory behind its use, and how volume signals are calibrated and discuss elements of P-V analysis. The goal is to provide a convenient summary of earlier investigations and insights for users whose primary interests lie in genetic/molecular studies rather than in biomedical engineering.
Collapse
Affiliation(s)
- Oscar H Cingolani
- Division of Cardiology, Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | |
Collapse
|