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Han B, Trew ML, Zgierski-Johnston CM. Cardiac Conduction Velocity, Remodeling and Arrhythmogenesis. Cells 2021; 10:cells10112923. [PMID: 34831145 PMCID: PMC8616078 DOI: 10.3390/cells10112923] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 10/14/2021] [Accepted: 10/22/2021] [Indexed: 02/06/2023] Open
Abstract
Cardiac electrophysiological disorders, in particular arrhythmias, are a key cause of morbidity and mortality throughout the world. There are two basic requirements for arrhythmogenesis: an underlying substrate and a trigger. Altered conduction velocity (CV) provides a key substrate for arrhythmogenesis, with slowed CV increasing the probability of re-entrant arrhythmias by reducing the length scale over which re-entry can occur. In this review, we examine methods to measure cardiac CV in vivo and ex vivo, discuss underlying determinants of CV, and address how pathological variations alter CV, potentially increasing arrhythmogenic risk. Finally, we will highlight future directions both for methodologies to measure CV and for possible treatments to restore normal CV.
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Affiliation(s)
- Bo Han
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen, 79110 Freiburg im Breisgau, Germany;
- Faculty of Medicine, University of Freiburg, 79110 Freiburg im Breisgau, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104 Freiburg im Breisgau, Germany
- Department of Cardiovascular Surgery, The Fourth People’s Hospital of Jinan, 250031 Jinan, China
| | - Mark L. Trew
- Auckland Bioengineering Institute, University of Auckland, Auckland 1010, New Zealand;
| | - Callum M. Zgierski-Johnston
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen, 79110 Freiburg im Breisgau, Germany;
- Faculty of Medicine, University of Freiburg, 79110 Freiburg im Breisgau, Germany
- Correspondence:
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Good WW, Gillette KK, Zenger B, Bergquist JA, Rupp LC, Tate J, Anderson D, Gsell MAF, Plank G, MacLeod RS. Estimation and Validation of Cardiac Conduction Velocity and Wavefront Reconstruction Using Epicardial and Volumetric Data. IEEE Trans Biomed Eng 2021; 68:3290-3300. [PMID: 33784613 DOI: 10.1109/tbme.2021.3069792] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE In this study, we have used whole heart simulations parameterized with large animal experiments to validate three techniques (two from the literature and one novel) for estimating epicardial and volumetric conduction velocity (CV). METHODS We used an eikonal-based simulation model to generate ground truth activation sequences with prescribed CVs. Using the sampling density achieved experimentally we examined the accuracy with which we could reconstruct the wavefront, and then examined the robustness of three CV estimation techniques to reconstruction related error. We examined a triangulation-based, inverse-gradient-based, and streamline-based techniques for estimating CV cross the surface and within the volume of the heart. RESULTS The reconstructed activation times agreed closely with simulated values, with 50-70% of the volumetric nodes and 97-99% of the epicardial nodes were within 1 ms of the ground truth. We found close agreement between the CVs calculated using reconstructed versus ground truth activation times, with differences in the median estimated CV on the order of 3-5% volumetrically and 1-2% superficially, regardless of what technique was used. CONCLUSION Our results indicate that the wavefront reconstruction and CV estimation techniques are accurate, allowing us to examine changes in propagation induced by experimental interventions such as acute ischemia, ectopic pacing, or drugs. SIGNIFICANCE We implemented, validated, and compared the performance of a number of CV estimation techniques. The CV estimation techniques implemented in this study produce accurate, high-resolution CV fields that can be used to study propagation in the heart experimentally and clinically.
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Ling S, Jenkins MW, Watanabe M, Ford SM, Rollins AM. Prenatal ethanol exposure impairs the conduction delay at the atrioventricular junction in the looping heart. Am J Physiol Heart Circ Physiol 2021; 321:H294-H305. [PMID: 34142884 PMCID: PMC8526336 DOI: 10.1152/ajpheart.00107.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 12/27/2022]
Abstract
The etiology of ethanol-related congenital heart defects has been the focus of much study, but most research has concentrated on cellular and molecular mechanisms. We have shown with optical coherence tomography (OCT) that ethanol exposure led to increased retrograde flow and smaller atrioventricular (AV) cushions compared with controls. Since AV cushions play a role in patterning the conduction delay at the atrioventricular junction (AVJ), this study aims to investigate whether ethanol exposure alters the AVJ conduction in early looping hearts and whether this alteration is related to the decreased cushion size. Quail embryos were exposed to a single dose of ethanol at gastrulation, and Hamburger-Hamilton stage 19-20 hearts were dissected for imaging. Cardiac conduction was measured using an optical mapping microscope and we imaged the endocardial cushions using OCT. Our results showed that, compared with controls, ethanol-exposed embryos exhibited abnormally fast AVJ conduction and reduced cushion size. However, this increased conduction velocity (CV) did not strictly correlate with decreased cushion volume and thickness. By matching the CV map to the cushion-size map along the inflow heart tube, we found that the slowest conduction location was consistently at the atrial side of the AVJ, which had the thinner cushions, not at the thickest cushion location at the ventricular side as expected. Our findings reveal regional differences in the AVJ myocardium even at this early stage in heart development. These findings reveal the early steps leading to the heterogeneity and complexity of conduction at the mature AVJ, a site where arrhythmias can be initiated.NEW & NOTEWORTHY To the best of our knowledge, this is the first study investigating the impact of ethanol exposure on the early cardiac conduction system. Our results showed that ethanol-exposed embryos exhibited abnormally fast atrioventricular conduction. In addition, our findings, in CV measurements and endocardial cushion thickness, reveal regional differences in the AVJ myocardium even at this early stage in heart development, suggesting that the differentiation and maturation at this site are complex and warrant further studies.
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Affiliation(s)
- Shan Ling
- Department of Biomedical Engineering, School of Engineering and School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Michael W Jenkins
- Department of Biomedical Engineering, School of Engineering and School of Medicine, Case Western Reserve University, Cleveland, Ohio
| | - Michiko Watanabe
- Department of Pediatrics, School of Medicine, Case Western Reserve University, Cleveland, Ohio
- Division of Pediatric Cardiology, The Congenital Heart Collaborative, Rainbow Babies and Children's Hospital, Cleveland, Ohio
| | - Stephanie M Ford
- Department of Pediatrics, School of Medicine, Case Western Reserve University, Cleveland, Ohio
- Division of Pediatric Cardiology, The Congenital Heart Collaborative, Rainbow Babies and Children's Hospital, Cleveland, Ohio
- Division of Neonatology, Rainbow Babies and Children's Hospital, Cleveland, Ohio
| | - Andrew M Rollins
- Department of Biomedical Engineering, School of Engineering and School of Medicine, Case Western Reserve University, Cleveland, Ohio
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Parahuleva MS, Kockskämper J, Heger J, Grimm W, Scherer A, Bühler S, Kreutz J, Schulz R, Euler G. Structural, Pro-Inflammatory and Calcium Handling Remodeling Underlies Spontaneous Onset of Paroxysmal Atrial Fibrillation in JDP2-Overexpressing Mice. Int J Mol Sci 2020; 21:E9095. [PMID: 33265909 PMCID: PMC7731172 DOI: 10.3390/ijms21239095] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 11/26/2020] [Accepted: 11/27/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Cardiac-specific JDP2 overexpression provokes ventricular dysfunction and atrial dilatation in mice. We performed in vivo studies on JDP2-overexpressing mice to investigate the impact of JDP2 on the predisposition to spontaneous atrial fibrillation (AF). METHODS JDP2-overexpression was started by withdrawal of a doxycycline diet in 4-week-old mice. The spontaneous onset of AF was documented by ECG within 4 to 5 weeks of JDP2 overexpression. Gene expression was analyzed by real-time RT-PCR and Western blots. RESULTS In atrial tissue of JDP2 mice, besides the 3.6-fold increase of JDP2 mRNA, no changes could be detected within one week of JDP2 overexpression. Atrial dilatation and hypertrophy, combined with elongated cardiomyocytes and fibrosis, became evident after 5 weeks of JDP2 overexpression. Electrocardiogram (ECG) recordings revealed prolonged PQ-intervals and broadened P-waves and QRS-complexes, as well as AV-blocks and paroxysmal AF. Furthermore, reductions were found in the atrial mRNA and protein level of the calcium-handling proteins NCX, Cav1.2 and RyR2, as well as of connexin40 mRNA. mRNA of the hypertrophic marker gene ANP, pro-inflammatory MCP1, as well as markers of immune cell infiltration (CD68, CD20) were increased in JDP2 mice. CONCLUSION JDP2 is an important regulator of atrial calcium and immune homeostasis and is involved in the development of atrial conduction defects and arrhythmogenic substrates preceding paroxysmal AF.
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Affiliation(s)
- Mariana S. Parahuleva
- Internal Medicine/Cardiology and Angiology, University Hospital of Giessen and Marburg, 35033 Marburg, Germany; (W.G.); (J.K.)
| | - Jens Kockskämper
- Biochemical-Pharmacological Centre (BPC) Marburg, Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043 Marburg, Germany; (J.K.); (A.S.); (S.B.)
| | - Jacqueline Heger
- Institute of Physiology, Justus Liebig University, 35392 Giessen, Germany; (J.H.); (R.S.); (G.E.)
| | - Wolfram Grimm
- Internal Medicine/Cardiology and Angiology, University Hospital of Giessen and Marburg, 35033 Marburg, Germany; (W.G.); (J.K.)
| | - Anna Scherer
- Biochemical-Pharmacological Centre (BPC) Marburg, Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043 Marburg, Germany; (J.K.); (A.S.); (S.B.)
| | - Sarah Bühler
- Biochemical-Pharmacological Centre (BPC) Marburg, Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043 Marburg, Germany; (J.K.); (A.S.); (S.B.)
| | - Julian Kreutz
- Internal Medicine/Cardiology and Angiology, University Hospital of Giessen and Marburg, 35033 Marburg, Germany; (W.G.); (J.K.)
| | - Rainer Schulz
- Institute of Physiology, Justus Liebig University, 35392 Giessen, Germany; (J.H.); (R.S.); (G.E.)
| | - Gerhild Euler
- Institute of Physiology, Justus Liebig University, 35392 Giessen, Germany; (J.H.); (R.S.); (G.E.)
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Antit S, Zakhama L, Belouer A, Boussabeh E, Thameur M, Ben Youssef S. Assessment of atrial conduction time by Doppler tissue imaging in hypertensive patients. Tunis Med 2020; 98:41-48. [PMID: 32395776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
BACKGROUND Hypertension is the first cause of atrial fibrillation. Its onset is explained by intricate mechanisms such as atrial conduction impairment. AIM To evaluate atrial conduction by tissue Doppler imaging in hypertensive patients compared to a control group. METHODS This is a comparative prospective study performed in the cardiology department of the FSI hospital enrolling 55 patients with hypertension and 55 controls. All of them underwent a complete echocardiocardiography exam with Doppler tissue imaging. We measured intraatrial and interatrial electromechanical delay by Pulsed Tissue Doppler. Statical analysis was conducted using SPSS version 22.0. Comparison of means was made with t student test. RESULTS Left ventricular mass and septal thikness were more important in the hypertensive group. Mitral A wave was greater in hypertensive group compared to controls (7,1cm/s vs 5,6cm/s; p<0,0001; respectively). Left atrial volume was of 32,7±6,8mL/m² in hypertensives vs 29,5±4,3 mL/m² in controls (p=0,006). Doppler Tissue study showed homogeneous statistically significant elongation of atrial conduction times in hypertensive patients compared to controls: interatrial time (16.8±7.8ms vs 12.4±4,2ms, p<0.0003) and left intraatrial (27.6±8.6ms vs 19.0±4.3ms, p<0.0001) and right intraatrial time (10.8±6.0ms vs 6.6±2.9ms, p<0.0001; respectively for hypertensive and control subjects. There was a significant correlation between measured intraatrial and interatrial electromechanical delays and duration of hypertension, indexed left atrial volume ans indexed left ventricular mass (r 0.27-0.41, p<0.001). CONCLUSION Atrial conduction time is significantly longer in hypertensive patients. Impairment of atrial conduction may be predictive of atrial fibrillation and should prompt closer surveillance to detect this arrhythmia in these patients.
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Haïssaguerre M, Nademanee W, Hocini M, Duchateau J, André C, Lavergne T, Takigawa M, Sacher F, Derval N, Pambrun T, Jais P, Walton R, Potse M, Vigmond E, Dubois R, Bernus O. The Spectrum of Idiopathic Ventricular Fibrillation and J-Wave Syndromes: Novel Mapping Insights. Card Electrophysiol Clin 2019; 11:699-709. [PMID: 31706476 DOI: 10.1016/j.ccep.2019.08.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Idiopathic ventricular fibrillation and J-wave syndromes are causes of sudden cardiac death (SCD) without any identified structural cardiac disease after extensive investigations. Recent data show that high-density electrophysiological mapping may ultimately offer diagnoses of subclinical diseases in most patients including those termed "unexplained" SCD. Three major conditions can underlie the occurrence of SCD: (1) localized depolarization abnormalities (due to microstructural myocardial alteration), (2) Purkinje abnormalities manifesting as triggering ectopy and inducible reentry; or (3) repolarization heterogeneities. Each condition may result from a spectrum of pathophysiologic processes with implications for individual therapy.
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Affiliation(s)
- Michel Haïssaguerre
- Electrophysiology and Cardiac Stimulation, Bordeaux University Hospital, 311 President Wilson Boulevard, Bordeaux 33200, France; IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France; Univ Bordeaux, CRCTB, U1045, Bordeaux, France.
| | | | - Mélèze Hocini
- Electrophysiology and Cardiac Stimulation, Bordeaux University Hospital, 311 President Wilson Boulevard, Bordeaux 33200, France; IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France; Univ Bordeaux, CRCTB, U1045, Bordeaux, France
| | - Josselin Duchateau
- Electrophysiology and Cardiac Stimulation, Bordeaux University Hospital, 311 President Wilson Boulevard, Bordeaux 33200, France; IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Clementine André
- Electrophysiology and Cardiac Stimulation, Bordeaux University Hospital, 311 President Wilson Boulevard, Bordeaux 33200, France; IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Thomas Lavergne
- IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Masa Takigawa
- Electrophysiology and Cardiac Stimulation, Bordeaux University Hospital, 311 President Wilson Boulevard, Bordeaux 33200, France
| | - Frederic Sacher
- Electrophysiology and Cardiac Stimulation, Bordeaux University Hospital, 311 President Wilson Boulevard, Bordeaux 33200, France; IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Nicolas Derval
- Electrophysiology and Cardiac Stimulation, Bordeaux University Hospital, 311 President Wilson Boulevard, Bordeaux 33200, France; IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Thomas Pambrun
- Electrophysiology and Cardiac Stimulation, Bordeaux University Hospital, 311 President Wilson Boulevard, Bordeaux 33200, France; IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Pierre Jais
- Electrophysiology and Cardiac Stimulation, Bordeaux University Hospital, 311 President Wilson Boulevard, Bordeaux 33200, France; IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Rick Walton
- IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Mark Potse
- IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Ed Vigmond
- IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Remi Dubois
- IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France
| | - Olivier Bernus
- IHU LIRYC, Electrophysiology and Heart Modeling Institute, Avenue du Haut Leveque, Bordeaux 33604, Passes Cedex, France; Univ Bordeaux, CRCTB, U1045, Bordeaux, France
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Magtibay K, Porta-Sánchez A, Haldar SK, Deno DC, Massé S, Nanthakumar K. Reinserting Physiology into Cardiac Mapping Using Omnipolar Electrograms. Card Electrophysiol Clin 2019; 11:525-536. [PMID: 31400876 DOI: 10.1016/j.ccep.2019.05.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Omnipolar electrograms (EGMs) make use of biophysical electric fields that accompany activation along the surface of the myocardium. A grid-like electrode array provides bipolar signals in orthogonal directions to deliver catheter-orientation-independent assessments of cardiac electrophysiology. Studies with myocyte monolayers, isolated animal and human hearts, and anesthetized animals validated the tenets of omnipolar EGMs. The combination of information from omnipolar-based activation vectors and voltages may aid in localizing areas of scar, lesion gaps, wavefront disorganization, and fractionation or collision during arrhythmias. The goal of omnipolar EGMs is to better characterize myocardium through reintroducing electrogram direction related fundamentals of cardiac electrophysiology.
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Affiliation(s)
- Karl Magtibay
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, University Health Network, 200 Elizabeth Street, Toronto, Ontario M5G 2C4, Canada
| | - Andreu Porta-Sánchez
- Hospital Universitario Quironsalud Madrid, Calle Diego de Velázquez, 1, 28223 Pozuelo de Alarcón, Madrid, Spain; Fundacion Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Melchor Fernández Almagro, 3, Madrid 28029, Spain
| | - Shouvik K Haldar
- Royal Brompton & Harefield NHS Foundation Trust, Harefield Hospital, Hill End Road, Harefield, Uxbridge UB9 6JH, UK
| | - Don Curtis Deno
- Abbott Laboratories, One St. Jude Medical Drive, St. Paul, MN 55117, USA
| | - Stéphane Massé
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, University Health Network, 200 Elizabeth Street, Toronto, Ontario M5G 2C4, Canada
| | - Kumaraswamy Nanthakumar
- The Hull Family Cardiac Fibrillation Management Laboratory, Toronto General Hospital, University Health Network, 200 Elizabeth Street, Toronto, Ontario M5G 2C4, Canada.
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Gómez-Álvarez Z, Gómez-Polo JC, Cobos-Gil MÁ. Response to ECG, April 2019. Rev Esp Cardiol (Engl Ed) 2019; 72:420. [PMID: 31003629 DOI: 10.1016/j.rec.2018.05.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 05/16/2018] [Indexed: 06/09/2023]
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Puertas A, Góngora J, Valverde M, Revelles L, Manzanares S, Carrillo MP. Cardiotocography alone vs. cardiotocography with ST segment analysis for intrapartum fetal monitoring in women with late-term pregnancy. A randomized controlled trial. Eur J Obstet Gynecol Reprod Biol 2019; 234:213-217. [PMID: 30731334 DOI: 10.1016/j.ejogrb.2019.01.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/17/2019] [Accepted: 01/18/2019] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Randomized studies have obtained conflicting results regarding the usefulness of fetal electrocardiographic (ECG) ST-segment analysis, possibly because these studies included non-homogeneous populations. We designed a study to determine whether this monitoring technique is potentially useful for populations at risk for fetal heart rate alterations during labor, i.e. groups of women who share late-term pregnancy as a risk factor. STUDY DESIGN This randomized clinical trial recruited women whose pregnancy had lasted more than 290 days. The participants were randomly assigned to continuous fetal cardiotocographic monitoring alone (CTG group) or with fetal ECG ST-segment analysis (ECG-F group). In the CTG group fetal heart rate was interpreted according to guidelines from the National Institute of Child Health and Human Development, whereas in the ECG-F group the tracings were interpreted according the original International Federation of Gynecology and Obstetrics (FIGO) guidelines. The primary outcome measure was neonatal outcome, evaluated as arterial blood pH in neonates after abdominal or vaginal operative delivery indicated because of nonreassuring fetal status. RESULTS A total of 237 women were randomized, of whom 200 were included in the final analysis (100 in each group). The rate of cesarean delivery was the same in both groups (26%), and the rate of operative delivery due to nonreassuring fetal status did not differ significantly (38% in the CTG group vs. 39% in the ECG-F group). Regarding neonatal outcomes, there was no significant difference between groups in neonatal pH (7.27 [7.23-7.29] and 7.25 [7.21-7.27]). CONCLUSIONS In a population comprising only late-term pregnancies, fetal ECG monitoring had no benefits for the mother or fetus. Additional studies are needed of protocols for using ST waveform analysis in selected population groups.
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Affiliation(s)
- Alberto Puertas
- Department of Obstetrics and Gynecology, Virgen de las Nieves University Hospital of Granada, Avda. Fuerzas Armadas s/n, 18014 Granada, Spain.
| | - Javier Góngora
- Department of Obstetrics and Gynecology, Hospital de Poniente, Almería, Spain
| | - Mercedes Valverde
- Department of Obstetrics and Gynecology, Hospital "Santa Ana", Motril, Spain
| | - Laura Revelles
- Department of Obstetrics and Gynecology, Virgen de las Nieves University Hospital of Granada, Avda. Fuerzas Armadas s/n, 18014 Granada, Spain
| | - Sebastian Manzanares
- Department of Obstetrics and Gynecology, Virgen de las Nieves University Hospital of Granada, Avda. Fuerzas Armadas s/n, 18014 Granada, Spain
| | - M Paz Carrillo
- Department of Obstetrics and Gynecology, Virgen de las Nieves University Hospital of Granada, Avda. Fuerzas Armadas s/n, 18014 Granada, Spain
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Pellizzón OA, Nannini S, Gonzalez MD. [Alternating bundle branch block in a supraventricular tachycardia: Which is the mechanism ?]. Medicina (B Aires) 2019; 79:197-200. [PMID: 31284254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023] Open
Abstract
Functional bundle branch block during a supraventricular tachycardia can be observed with shorter cycle lengths and represent a physiologic response by the specialized intraventricular conduction system to accelerated AV nodal conduction. The present case corresponds to a young patient with exercise induced orthodromic A-V reentrant tachycardia and alternating bundle branch block. This unusual response is explained by the finding obtained during the electrophysiology study. An accelerated AV nodal conduction made the depolarizing wave front reach the bundle branches during their refractory period. Once block in one bundle was stablished, block persisted due to the linking phenomenon that is repetitive retrograde concealed conduction from the contralateral bundle. After catheter ablation of a concealed left-sided accessory A-V pathway, rapid atrial pacing at the same cycle length of the tachycardia reproduced the same aberrancies observed during tachycardia. This response proved that functional bundle branch block is due to the short cycle length and not the presence of an accessory A-V pathway.
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Affiliation(s)
- Oscar A Pellizzón
- Centro de Arritmias Cardíacas, Servicio de Cardiología, Hospital Provincial del Centenario, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Santa Fe, Argentina. E-mail:
| | - Sebastián Nannini
- Centro de Arritmias Cardíacas, Servicio de Cardiología, Hospital Provincial del Centenario, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Santa Fe, Argentina
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Martin CA, Orini M, Srinivasan NT, Bhar-Amato J, Honarbakhsh S, Chow AW, Lowe MD, Ben-Simon R, Elliott PM, Taggart P, Lambiase PD. Assessment of a conduction-repolarisation metric to predict Arrhythmogenesis in right ventricular disorders. Int J Cardiol 2018; 271:75-80. [PMID: 29871808 PMCID: PMC6152588 DOI: 10.1016/j.ijcard.2018.05.063] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/16/2018] [Accepted: 05/18/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND The re-entry vulnerability index (RVI) is a recently proposed activation-repolarization metric designed to quantify tissue susceptibility to re-entry. This study aimed to test feasibility of an RVI-based algorithm to predict the earliest endocardial activation site of ventricular tachycardia (VT) during electrophysiological studies and occurrence of haemodynamically significant ventricular arrhythmias in follow-up. METHODS Patients with Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) (n = 11), Brugada Syndrome (BrS) (n = 13) and focal RV outflow tract VT (n = 9) underwent programmed stimulation with unipolar electrograms recorded from a non-contact array in the RV. RESULTS Lowest values of RVI co-localised with VT earliest activation site in ARVC/BrS but not in focal VT. The distance between region of lowest RVI and site of VT earliest site (Dmin) was lower in ARVC/BrS than in focal VT (6.8 ± 6.7 mm vs 26.9 ± 13.3 mm, p = 0.005). ARVC/BrS patients with inducible VT had lower Global-RVI (RVIG) than those who were non-inducible (-54.9 ± 13.0 ms vs -35.9 ± 8.6 ms, p = 0.005) or those with focal VT (-30.6 ± 11.5 ms, p = 0.001). Patients were followed up for 112 ± 19 months. Those with clinical VT events had lower Global-RVI than both ARVC and BrS patients without VT (-54.5 ± 13.5 ms vs -36.2 ± 8.8 ms, p = 0.007) and focal VT patients (-30.6 ± 11.5 ms, p = 0.002). CONCLUSIONS RVI reliably identifies the earliest RV endocardial activation site of VT in BrS and ARVC but not focal ventricular arrhythmias and predicts the incidence of haemodynamically significant arrhythmias. Therefore, RVI may be of value in predicting VT exit sites and hence targeting of re-entrant arrhythmias.
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Affiliation(s)
- C A Martin
- Barts Heart Centre, Barts Health NHS Trust, West Smithfield, London EC1A 7BE, UK; Institute of Cardiovascular Science, University College London, Gower Street, London WC1E 6BT, UK
| | - M Orini
- Barts Heart Centre, Barts Health NHS Trust, West Smithfield, London EC1A 7BE, UK; Institute of Cardiovascular Science, University College London, Gower Street, London WC1E 6BT, UK
| | - N T Srinivasan
- Barts Heart Centre, Barts Health NHS Trust, West Smithfield, London EC1A 7BE, UK; Institute of Cardiovascular Science, University College London, Gower Street, London WC1E 6BT, UK
| | - J Bhar-Amato
- Institute of Cardiovascular Science, University College London, Gower Street, London WC1E 6BT, UK
| | - S Honarbakhsh
- Barts Heart Centre, Barts Health NHS Trust, West Smithfield, London EC1A 7BE, UK
| | - A W Chow
- Barts Heart Centre, Barts Health NHS Trust, West Smithfield, London EC1A 7BE, UK
| | - M D Lowe
- Barts Heart Centre, Barts Health NHS Trust, West Smithfield, London EC1A 7BE, UK
| | - R Ben-Simon
- Barts Heart Centre, Barts Health NHS Trust, West Smithfield, London EC1A 7BE, UK
| | - P M Elliott
- Barts Heart Centre, Barts Health NHS Trust, West Smithfield, London EC1A 7BE, UK
| | - P Taggart
- Institute of Cardiovascular Science, University College London, Gower Street, London WC1E 6BT, UK
| | - P D Lambiase
- Barts Heart Centre, Barts Health NHS Trust, West Smithfield, London EC1A 7BE, UK; Institute of Cardiovascular Science, University College London, Gower Street, London WC1E 6BT, UK.
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12
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Kany S, Saguner AM. [Usefulness of Electroanatomical Mapping in Rhythmology]. Praxis (Bern 1994) 2018; 107:1325-1331. [PMID: 30482115 DOI: 10.1024/1661-8157/a003129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Usefulness of Electroanatomical Mapping in Rhythmology Abstract. Atrial fibrillation is the most common arrhythmia and its prevalence is rising. Therapeutic options include drug treatment and interventional catheter ablation via pulmonary vein isolation (PVI). This procedure was associated with long fluoroscopy times which carried risks for patients and physicians. Electroanatomical mapping (EAM) is a tool to visualize anatomy, voltage and activation of the heart chambers. Current EAM systems used in clinical practice include CARTO®, EnSite NavX® and Rhythmia®. Magnetic fields and impendance approaches are used to create 3D shells of the chambers. The catheter can be used to either collect electrograms or to ablate the target tissue. When using EAM, fluoroscopy time is significantly decreased, and complications can be monitored. Images from CT, MRI or intracardiac echo can be used as a template for creating a map or merged with an existing map to enhance anatomic accuracy.
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Affiliation(s)
- Shinwan Kany
- 1 Klinik für Kardiologie, Universitäres Herzzentrum Zürich
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Hansen BJ, Csepe TA, Zhao J, Ignozzi AJ, Hummel JD, Fedorov VV. Maintenance of Atrial Fibrillation: Are Reentrant Drivers With Spatial Stability the Key? Circ Arrhythm Electrophysiol 2018; 9:CIRCEP.116.004398. [PMID: 27729340 DOI: 10.1161/circep.116.004398] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 09/07/2016] [Indexed: 11/16/2022]
Affiliation(s)
- Brian J Hansen
- From the Department of Physiology and Cell Biology, Ohio State University Wexner Medical Center, Columbus (B.J.H., T.A.C., A.J.I., J.D.H., V.V.F.); and Auckland Bioengineering Institute, The University of Auckland, New Zealand (J.Z.)
| | - Thomas A Csepe
- From the Department of Physiology and Cell Biology, Ohio State University Wexner Medical Center, Columbus (B.J.H., T.A.C., A.J.I., J.D.H., V.V.F.); and Auckland Bioengineering Institute, The University of Auckland, New Zealand (J.Z.)
| | - Jichao Zhao
- From the Department of Physiology and Cell Biology, Ohio State University Wexner Medical Center, Columbus (B.J.H., T.A.C., A.J.I., J.D.H., V.V.F.); and Auckland Bioengineering Institute, The University of Auckland, New Zealand (J.Z.)
| | - Anthony J Ignozzi
- From the Department of Physiology and Cell Biology, Ohio State University Wexner Medical Center, Columbus (B.J.H., T.A.C., A.J.I., J.D.H., V.V.F.); and Auckland Bioengineering Institute, The University of Auckland, New Zealand (J.Z.)
| | - John D Hummel
- From the Department of Physiology and Cell Biology, Ohio State University Wexner Medical Center, Columbus (B.J.H., T.A.C., A.J.I., J.D.H., V.V.F.); and Auckland Bioengineering Institute, The University of Auckland, New Zealand (J.Z.)
| | - Vadim V Fedorov
- From the Department of Physiology and Cell Biology, Ohio State University Wexner Medical Center, Columbus (B.J.H., T.A.C., A.J.I., J.D.H., V.V.F.); and Auckland Bioengineering Institute, The University of Auckland, New Zealand (J.Z.).
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Wang H, Che X. Case report: an unstable wide QRS complexes tachycardia after ablation of a poster-septal accessory pathway: What is the mechanism? Medicine (Baltimore) 2018. [PMID: 29538207 PMCID: PMC5882396 DOI: 10.1097/md.0000000000010120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
INTRODUCTION Differentiation of wide QRS complex tachycardia required repeated electrophysiological stimuli and mapping. However, instability of tachycardia would increase the difficulty in differential diagnosis. SYMPTOMS AND CLINICAL FINDINGS In this paper, we reported a wide QRS tachycardia following ablation of an atrioventricular reentrant tachycardia participated by a poster-septal accessory pathway. Limited differentiation strategy was performed because the wide QRS tachycardia was self-limited and with unstable hemodynamics. We analyzed the mechanism of the wide QRS tachycardia by only 4 beats ventricular overpacing. On the basis of the last ventricular pacing, an atypical atrioventricular nodal reentrant tachycardia was confirmed. INTERVENTION AND OUTCOMES After slow-pathway modification, the wide QRS tachycardia was eliminated. CONCLUSION It was an atypical atrial-ventricular node reentrant tachycardia with right bundle branch block. Reasonable analysis based on electrophysiological electrophysiologic knowledge was the basis of successful diagnosis and treatment.
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Affiliation(s)
- Huan Wang
- Department of Cardiology, Zhejiang Province People's Hospital
- Department of Cardiology People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang Province, China
| | - Xiaoru Che
- Department of Cardiology, Zhejiang Province People's Hospital
- Department of Cardiology People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang Province, China
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Abstract
To investigate the diagnostic value of electrocardiographic (ECG) ST-segment in acute inferior myocardial infarction (AIMI) caused by the left circumflex branch (LCX).A total of 240 clinical cases with AIMI in our hospital were retrospectively analyzed. All of them had received percutaneous coronary intervention (PCI) within 12 hours after symptom onset. The clinical features, ECG manifestations, and coronary artery lesion characteristics of the patients were collected.The right coronary artery (RCA) was shown to be the infarct-related artery (IRA) in 177 patients, while LCX was responsible for AIMI in 63 cases. There was no significant difference in the risk factors of coronary heart disease (CHD) (P > .05 for all) between the 2 groups. ST-segment elevation in lead II, III, and AVF could be found in all patients. Moreover, ST-segment depression in lead I (STD I), ST-segment elevation in lead III (STE III), STE III-STE II, STE AVF, STD AVL, STD AVL-STD I and STE v6 lead ST-segment deviation exhibited significant difference in 2 groups (P < .05 for all). The changes of STD I, STE III < STEII, STD AVL < STD I could discriminate between LCX and RCA in AIMI patients with high sensitivity and specificity.ECG may be an effective tool to predict the IRA in patient with AIMI.
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16
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Park SJ, Kwon CH, Bae BJ, Kim BS, Kim SH, Kim HJ, Hwang HK, Chung SM. Diagnostic value of the corrected QT difference between leads V1 and V6 in patients with acute pulmonary thromboembolism. Medicine (Baltimore) 2017; 96:e8430. [PMID: 29069044 PMCID: PMC5671877 DOI: 10.1097/md.0000000000008430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
In acute pulmonary thromboembolism (PTE), right ventricular pressure overload impairs right-sided cardiac conduction and repolarization. We hypothesized that if heterogeneity of repolarization between right and left ventricles occurs in acute PTE, there would be the difference of repolarization between them. Therefore, we aimed to evaluate the diagnostic value of corrected QT interval (QTc) difference between leads V1 and V6 (V1 - V6) in patients with acute PTE.A total of 89 patients with suspected acute PTE who underwent computed tomographic angiography (CTA) were enrolled from January to December 2015. PTE was identified by CTA. We compared electrocardiographic (ECG) parameters, especially QTc difference (V1 - V6) between patients with PTE and those without PTE.Acute PTE was finally diagnosed in 45 patients. Clinical situations including the chief complaint were not different between PTE and non-PTE groups. S1Q3T3, a traditional ECG marker, had no diagnostic value for acute PTE. Patients with PTE had a significantly longer mean QTc in V1 (454.6 ± 44.3 vs 417.5 ± 31.3 ms, P < .001) and larger QTc difference (V1 - V6) (34.8 ± 30.5 vs -12.5 ± 16.6 ms, P < .001) than non-PTE controls. QTc difference (V1 - V6) was negative in all patients without PTE. PTE patients had a higher prevalence of T wave inversion in leads III (51.1% vs 29.5%, P = .038) and V1 (82.2% vs 38.6%, P < .001). A QTc difference (V1 - V6) of ≥20 ms identified PTE with 82.2% sensitivity, 100.0% specificity, and 100.0% positive predictive value.QTc difference (V1 - V6) had an excellent diagnostic value for differentiating patients with and without acute PTE.
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17
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Stephenson RS, Atkinson A, Kottas P, Perde F, Jafarzadeh F, Bateman M, Iaizzo PA, Zhao J, Zhang H, Anderson RH, Jarvis JC, Dobrzynski H. High resolution 3-Dimensional imaging of the human cardiac conduction system from microanatomy to mathematical modeling. Sci Rep 2017; 7:7188. [PMID: 28775383 PMCID: PMC5543124 DOI: 10.1038/s41598-017-07694-8] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 07/03/2017] [Indexed: 12/23/2022] Open
Abstract
Cardiac arrhythmias and conduction disturbances are accompanied by structural remodelling of the specialised cardiomyocytes known collectively as the cardiac conduction system. Here, using contrast enhanced micro-computed tomography, we present, in attitudinally appropriate fashion, the first 3-dimensional representations of the cardiac conduction system within the intact human heart. We show that cardiomyocyte orientation can be extracted from these datasets at spatial resolutions approaching the single cell. These data show that commonly accepted anatomical representations are oversimplified. We have incorporated the high-resolution anatomical data into mathematical simulations of cardiac electrical depolarisation. The data presented should have multidisciplinary impact. Since the rate of depolarisation is dictated by cardiac microstructure, and the precise orientation of the cardiomyocytes, our data should improve the fidelity of mathematical models. By showing the precise 3-dimensional relationships between the cardiac conduction system and surrounding structures, we provide new insights relevant to valvar replacement surgery and ablation therapies. We also offer a practical method for investigation of remodelling in disease, and thus, virtual pathology and archiving. Such data presented as 3D images or 3D printed models, will inform discussions between medical teams and their patients, and aid the education of medical and surgical trainees.
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Affiliation(s)
- Robert S Stephenson
- Comparative Medicine Lab, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - Andrew Atkinson
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Petros Kottas
- School of Physics and Astronomy, University of Manchester, Manchester, UK
| | - Filip Perde
- National Institute of Legal Medicine, Bucharest, Romania
| | - Fatemeh Jafarzadeh
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Mike Bateman
- The Visible Heart Laboratory, University of Minnesota, Minneapolis, USA
| | - Paul A Iaizzo
- The Visible Heart Laboratory, University of Minnesota, Minneapolis, USA
| | - Jichao Zhao
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Henggui Zhang
- School of Physics and Astronomy, University of Manchester, Manchester, UK
| | - Robert H Anderson
- Institute of Genetic Medicine, University of Newcastle, Newcastle, UK
| | - Jonathan C Jarvis
- School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.
| | - Halina Dobrzynski
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
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18
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Avitall B, Kalinski A, Kocheril GS, Laske TG, Coulombe N. Novel dyeless and fluoro-less approach to cryoballoon pulmonary vein occlusion assessment. Heart Rhythm 2017; 14:1241-1246. [PMID: 28506919 DOI: 10.1016/j.hrthm.2017.05.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Indexed: 11/19/2022]
Abstract
BACKGROUND Pulmonary vein (PV) occlusion is essential for PV isolation (PVI) using the cryoballoon. Currently occlusion is arbitrarily determined using fluoroscopy and contrast media. This study aimed to create an objective measure without utilizing excessive fluoroscopy and using no contrast media. OBJECTIVE To ensure PV occlusion without fluoroscopy and contrast dye. METHODS In 4 in vivo hearts 113 PV occlusions were tested with a 50% cold dye saline mix at 4°C. Occlusions were rated Good, Fair, and Poor by dye dissipation seen via fluoroscopy and correlated to temperature profiles recorded concurrently. Using these temperature profiles and no dye, cryoablations were placed in 12 additional hearts (56 unique veins, 126 occlusions). Two 180-second cryoablation applications were placed per vein with occlusion testing in between. PVI was defined by electrophysiology mapping, gross pathology, and histology after ≥4 weeks recovery. RESULTS Dye results were as follows: With Good, Fair, and Poor the maximal postinjection PV temperature dropped (ΔT) by 6.2 ± 4.2°C, 5.1 ± 3.7°C, and 2.4 ± 2.0°C. At 5 seconds post nadir temperature, injection temperature recovered 18% ± 14%, 36% ± 23%, and 50% ± 33%. Console thaw time to 0°C was 11.5 ± 4.8 seconds, 8.5 ± 2.1 seconds, and 4.3 ± 1.3 seconds. Success rate for PVI was 100%, 97%, and 0%. With no dye: ΔT: 7.7 ± 4.4°C, 5.8 ± 5.0°C, and 3.4 ± 2.3°C; % recovery at 5 seconds: 15% ± 12%, 31% ± 23%, 45% ± 30%; thaw time to 0°C: 11.9 ± 4.8 seconds, 10.5 ± 5.2 seconds, 6.0 ± 2.8 seconds; success rate: 97%, 91%, and 10%. CONCLUSION PV occlusion profile determination using 4°C cold saline injection is an effective approach to define the occlusion grade. Quality occlusions correlate strongly with PVI success.
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19
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Dodd KW, Elm KD, Dodd EM, Smith SW. Among patients with left bundle branch block, T-wave peak to T-wave end time is prolonged in the presence of acute coronary occlusion. Int J Cardiol 2017; 236:1-4. [PMID: 28082087 DOI: 10.1016/j.ijcard.2017.01.064] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 12/20/2016] [Accepted: 01/06/2017] [Indexed: 11/17/2022]
Abstract
BACKGROUND Assessing the effect of myocardial ischemia on ventricular repolarization in the setting of left bundle branch block (LBBB) poses a challenge due to secondary prolongation of the QT interval inherent in LBBB. The T-wave peak to T-wave end (TpTe) interval has been noted to prolong during myocardial ischemia and correct after reperfusion in patients with normal conduction. Here we compare the TpTe intervals of patients with LBBB both with and without complete acute coronary occlusion (ACO). METHODS Retrospectively, emergency department patients with LBBB and symptoms of myocardial ischemia were identified both with angiographically-proven ACO and with No-ACO. The longest QT, JT, and TpTe intervals were analyzed. RESULTS The ACO and No-ACO groups consisted of 33 and 129 patients, respectively. The mean TpTe was longer in ACO (103.6ms [95%CI 98.5-108.7]) compared to No-ACO patients (88.6ms [95%CI 85.3-91.9]) (P<0.0001) and this held true after correction for heart rate. In ACO versus No-ACO, the TpTe also more frequently exceeded prolongation cutoffs of 85ms (30 [90%] versus 69 [54%]) and 100ms (25 [76%] versus 42 [33%]) (P<0.0001 for all). The mean QT, JT, QTc, and JTc intervals were not significantly different between the groups for either the Bazett's or Rautaharju's correction formulas. CONCLUSIONS In patients with LBBB on the ECG, the TpTe is longer and more frequently prolonged in patients with ACO compared to patients without ACO. Future studies of ventricular repolarization in patients with LBBB should include analyses of the TpTe interval.
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Affiliation(s)
- Kenneth W Dodd
- Department of Emergency Medicine, Hennepin County Medical Center, Division of Critical Care Medicine, Department of Medicine, Hennepin County Medical Center, United States.
| | - Kendra D Elm
- Department of Emergency Medicine, Hennepin County Medical Center, United States
| | - Erin M Dodd
- University of Minnesota Medical School, United States
| | - Stephen W Smith
- Department of Emergency Medicine, Hennepin County Medical Center, Department of Emergency Medicine, University of Minnesota Medical School, United States
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20
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Yalcinkaya E, Winnik S, Haegeli L, Brunckhorst C, Duru F. Successful Cryoablation of an Anteroseptal Accessory Pathway Guided by Electroanatomical Activation Mapping. J Invasive Cardiol 2016; 28:E227. [PMID: 27922815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The use of electroanatomical mapping can facilitate the identification of the ideal cryoablation site by providing a three-dimensional map of the earliest activation site. Combined use of the cryoablation technology with electroanatomical mapping can further increase the precision and safety of the procedure by applying test applications at a lower energy level.
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Affiliation(s)
- Emre Yalcinkaya
- Arrhythmia and Electrophysiology Division, University Heart Center, 8091, Zurich, Switzerland.
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21
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Yang F, Zhang L, Lu W, Liu L, Zhang Y, Zuo W, Wang K, Zhang H. Depth Attenuation Degree Based Visualization for Cardiac Ischemic Electrophysiological Feature Exploration. Biomed Res Int 2016; 2016:2979081. [PMID: 28004002 PMCID: PMC5150122 DOI: 10.1155/2016/2979081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 09/21/2016] [Accepted: 10/11/2016] [Indexed: 01/23/2023]
Abstract
Although heart researches and acquirement of clinical and experimental data are progressively open to public use, cardiac biophysical functions are still not well understood. Due to the complex and fine structures of the heart, cardiac electrophysiological features of interest may be occluded when there is a necessity to demonstrate cardiac electrophysiological behaviors. To investigate cardiac abnormal electrophysiological features under the pathological condition, in this paper, we implement a human cardiac ischemic model and acquire the electrophysiological data of excitation propagation. A visualization framework is then proposed which integrates a novel depth weighted optic attenuation model into the pathological electrophysiological model. The hidden feature of interest in pathological tissue can be revealed from sophisticated overlapping biophysical information. Experiment results verify the effectiveness of the proposed method for intuitively exploring and inspecting cardiac electrophysiological activities, which is fundamental in analyzing and explaining biophysical mechanisms of cardiac functions for doctors and medical staff.
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Affiliation(s)
- Fei Yang
- School of Mechanical, Electrical & Information Engineering, Shandong University, Weihai 264200, China
| | - Lei Zhang
- School of Art and Design, Harbin University, Harbin 150086, China
| | - Weigang Lu
- Department of Educational Technology, Ocean University of China, Qingdao 266100, China
| | - Lei Liu
- Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China
| | - Yue Zhang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Wangmeng Zuo
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Kuanquan Wang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin 150001, China
| | - Henggui Zhang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin 150001, China
- School of Physics and Astronomy, University of Manchester, Manchester M139PL, UK
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22
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Salas J, Castellanos E, Peinado R, Madero S, Barrio-López T, Ortiz M, Almendral J. Atrial mapping during pulmonary vein pacing: a novel maneuver to detect and close residual conduction gaps in an ablation line. J Interv Card Electrophysiol 2016; 47:299-307. [PMID: 27371411 PMCID: PMC5110596 DOI: 10.1007/s10840-016-0159-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 06/17/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Location of residual conduction gaps on ablation lines around pulmonary veins (PV) is challenging, and several maneuvers have been described. Atrial mapping during PV pacing-the "pace and map" maneuver-could localize gaps. METHODS AND RESULTS We prospectively studied 209 patients undergoing PV isolation at a single institution over a 25-month period. In 24 (11.4 %) patients, 26 PV remained connected after an ablation line and an initial conventional gap closure protocol. The atrial side of the ablation line was mapped with the ablation catheter during PV pacing, and the earliest site was considered a gap site. Ablation at these gap sites resulted in bidirectional PV conduction block in 22 PV (85 %) in 21 patients (88 %), after 2.2 ± 1.6 radiofrequency applications and 8.2 ± 4.8 min. Early PV reconnection (≥20 min) occurred in 0 PV (0 %). During a mean follow-up of 12 ± 6 months, eight patients (33 %) had arrhythmia recurrences. CONCLUSIONS The "pace and map" maneuver is a relatively simple and efficacious means to identify gaps in ablation lines around PV, focusing on the atrial rather than the PV side of the line. It could be considered among the ways to eliminate residual conduction gaps.
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Affiliation(s)
- Jefferson Salas
- Electrophysiology Laboratory and Arrhythmia Unit, Hospital Monteprincipe, Grupo HM Hospitales, University CEU-San Pablo, Madrid, Spain.
| | - Eduardo Castellanos
- Electrophysiology Laboratory and Arrhythmia Unit, Hospital Monteprincipe, Grupo HM Hospitales, University CEU-San Pablo, Madrid, Spain
| | - Rafael Peinado
- Electrophysiology Laboratory and Arrhythmia Unit, Hospital Monteprincipe, Grupo HM Hospitales, University CEU-San Pablo, Madrid, Spain
| | - Sergio Madero
- Electrophysiology Laboratory and Arrhythmia Unit, Hospital Monteprincipe, Grupo HM Hospitales, University CEU-San Pablo, Madrid, Spain
| | - Teresa Barrio-López
- Electrophysiology Laboratory and Arrhythmia Unit, Hospital Monteprincipe, Grupo HM Hospitales, University CEU-San Pablo, Madrid, Spain
| | - Mercedes Ortiz
- Electrophysiology Laboratory and Arrhythmia Unit, Hospital Monteprincipe, Grupo HM Hospitales, University CEU-San Pablo, Madrid, Spain
| | - Jesús Almendral
- Electrophysiology Laboratory and Arrhythmia Unit, Hospital Monteprincipe, Grupo HM Hospitales, University CEU-San Pablo, Madrid, Spain
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Zahid S, Whyte KN, Schwarz EL, Blake RC, Boyle PM, Chrispin J, Prakosa A, Ipek EG, Pashakhanloo F, Halperin HR, Calkins H, Berger RD, Nazarian S, Trayanova NA. Feasibility of using patient-specific models and the "minimum cut" algorithm to predict optimal ablation targets for left atrial flutter. Heart Rhythm 2016; 13:1687-98. [PMID: 27108938 DOI: 10.1016/j.hrthm.2016.04.009] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Indexed: 11/19/2022]
Abstract
BACKGROUND Left atrial flutter (LAFL) occurs in patients after atrial fibrillation ablation. Identification of optimal ablation targets to terminate LAFL remains challenging. OBJECTIVE The purpose of this study was to use patient-specific models to simulate LAFL and predict optimal ablation targets using a novel approach based on flow network theory. METHODS Late gadolinium-enhanced cardiac magnetic resonance scans from 10 patients with LAFL were used to construct atrial models incorporating fibrosis by investigators blinded to procedural findings. Rapid pacing was applied in silico to induce LAFL. In each LAFL, we represented reentrant wave propagation as an electric flow network and identified the "minimum cut" (MC), which was the smallest amount of tissue that separated the flow into 2 discontinuous components. In silico ablation was applied at MCs, and targets were compared to those that terminated LAFL during catheter ablation. RESULTS Patient-specific atrial models were successfully generated from patient scans. LAFL was induced in 7 of 10 models. Ablation of MCs terminated LAFL in 4 models and produced new, slower LAFL morphologies in the other 3. For the latter cases, flow analysis was repeated to identify MCs of emergent LAFLs. Ablation of these MCs terminated emergent LAFLs. The MC-based ablation lesions in simulations were similar in length and location to ablation targets that terminated LAFL during catheter ablation for these 7 patients. CONCLUSION Personalized atrial simulations can predict ablation targets for LAFL. These simulations provide a powerful tool for planning ablation procedures and may reduce procedural times and complications.
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Affiliation(s)
- Sohail Zahid
- Institute for Computational Medicine, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Kaitlyn N Whyte
- Institute for Computational Medicine, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Erica L Schwarz
- Institute for Computational Medicine, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Robert C Blake
- CardioSolv Ablation Technologies Inc, Baltimore, Maryland
| | - Patrick M Boyle
- Institute for Computational Medicine, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Jonathan Chrispin
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Adityo Prakosa
- Institute for Computational Medicine, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Esra G Ipek
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Farhad Pashakhanloo
- Institute for Computational Medicine, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Henry R Halperin
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hugh Calkins
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ronald D Berger
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Saman Nazarian
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Epidemiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Natalia A Trayanova
- Institute for Computational Medicine, Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland; Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.
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Chen CJ, Lin SJ, Lu YH, Lee KT. Accessory conduction pathway ablated by myocarditis in a patient with Wolff-Parkinson-White syndrome. Kaohsiung J Med Sci 2015; 31:550-1. [PMID: 26520696 DOI: 10.1016/j.kjms.2015.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Revised: 07/27/2015] [Accepted: 08/12/2015] [Indexed: 11/17/2022] Open
Affiliation(s)
- Chang-Jen Chen
- Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Shin-Jing Lin
- Cardiovascular Center, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Ye-Hsu Lu
- Cardiovascular Center, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Kun-Tai Lee
- Cardiovascular Center, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Internal Medicine, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
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Tsyganov A, Petru J, Skoda J, Sediva L, Hala P, Weichet J, Janotka M, Chovanec M, Neuzil P, Reddy VY. Anatomical predictors for successful pulmonary vein isolation using balloon-based technologies in atrial fibrillation. J Interv Card Electrophysiol 2015; 44:265-71. [PMID: 26475792 DOI: 10.1007/s10840-015-0068-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Accepted: 10/07/2015] [Indexed: 12/20/2022]
Abstract
PURPOSE We evaluated the correlation between pulmonary venous (PV) anatomy and acute and long-term success of PV isolation (PVI) with two balloon-based ablation catheter techniques. METHODS One hundred consecutive patients were analyzed in two equal groups treated with either the second-generation cryoballoon (CRYO) catheter or the visually guided laser ablation (VGLA) catheter. All patients underwent multi-detector computed tomography (CT) imaging. The primary and secondary efficacy endpoints were the procedural achievement of proven electrical isolation of all veins and freedom from atrial fibrillation (AF) within a 1-year follow-up period, respectively. RESULTS Variant PV anatomy was observed in 32% of patients in the CRYO group and in 40% of patients in the VGLA group. All PVs were targeted with either the CRYO catheter (n = 199) or the VGLA catheter (n = 206). One hundred ninety-three of 199 PVs (97%) were successfully isolated in the CRYO group and 194 of 206 PVs (94%) in the VGLA group (p = 0.83). Over a 12-month follow-up, AF recurrence was documented in 11/45 (24%) and 7/43 (16%) patients in the CRYO and the VGLA groups, respectively (p = 0.21). In the CRYO group, a larger left inferior PV size was associated with worse long-term outcome (p = 0.001). In the VGLA group, a larger left superior PV size (p = 0.003) and more oval right inferior PV were associated with worse acute success (p = 0.038). There was no absolute cutoff between PV anatomy and clinical success. CONCLUSIONS The variability of PV anatomy did not significantly compromise acute success of PVI or patient outcomes.
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Affiliation(s)
- Alexey Tsyganov
- Na Homolce Hospital, Prague, Czech Republic.
- Petrovsky National Research Centre of Surgery, Moscow, Russia.
| | - Jan Petru
- Na Homolce Hospital, Prague, Czech Republic
| | - Jan Skoda
- Na Homolce Hospital, Prague, Czech Republic
| | | | - Pavel Hala
- Na Homolce Hospital, Prague, Czech Republic
| | | | | | | | | | - Vivek Y Reddy
- The Helmsley Electrophysiology Centre, Mount Sinai School of Medicine, New York, NY, US
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Lau E, Kossidas K, Kim TY, Kunitomo Y, Ziv O, Zhen S, Taylor C, Schofield L, Yammine J, Liu G, Peng X, Qu Z, Koren G, Choi BR. Spatially Discordant Alternans and Arrhythmias in Tachypacing-Induced Cardiac Myopathy in Transgenic LQT1 Rabbits: The Importance of IKs and Ca2+ Cycling. PLoS One 2015; 10:e0122754. [PMID: 25970695 PMCID: PMC4430457 DOI: 10.1371/journal.pone.0122754] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 02/12/2015] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Remodeling of cardiac repolarizing currents, such as the downregulation of slowly activating K+ channels (IKs), could underlie ventricular fibrillation (VF) in heart failure (HF). We evaluated the role of Iks remodeling in VF susceptibility using a tachypacing HF model of transgenic rabbits with Long QT Type 1 (LQT1) syndrome. METHODS AND RESULTS LQT1 and littermate control (LMC) rabbits underwent three weeks of tachypacing to induce cardiac myopathy (TICM). In vivo telemetry demonstrated steepening of the QT/RR slope in LQT1 with TICM (LQT1-TICM; pre: 0.26±0.04, post: 0.52±0.01, P<0.05). In vivo electrophysiology showed that LQT1-TICM had higher incidence of VF than LMC-TICM (6 of 11 vs. 3 of 11, respectively). Optical mapping revealed larger APD dispersion (16±4 vs. 38±6 ms, p<0.05) and steep APD restitution in LQT1-TICM compared to LQT1-sham (0.53±0.12 vs. 1.17±0.13, p<0.05). LQT1-TICM developed spatially discordant alternans (DA), which caused conduction block and higher-frequency VF (15±1 Hz in LQT1-TICM vs. 13±1 Hz in LMC-TICM, p<0.05). Ca2+ DA was highly dynamic and preceded voltage DA in LQT1-TICM. Ryanodine abolished DA in 5 out of 8 LQT1-TICM rabbits, demonstrating the importance of Ca2+ in complex DA formation. Computer simulations suggested that HF remodeling caused Ca2+-driven alternans, which was further potentiated in LQT1-TICM due to the lack of IKs. CONCLUSIONS Compared with LMC-TICM, LQT1-TICM rabbits exhibit steepened APD restitution and complex DA modulated by Ca2+. Our results strongly support the contention that the downregulation of IKs in HF increases Ca2+ dependent alternans and thereby the risk of VF.
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Affiliation(s)
- Emily Lau
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Konstantinos Kossidas
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Tae Yun Kim
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Yukiko Kunitomo
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Ohad Ziv
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Song Zhen
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Chantel Taylor
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Lorraine Schofield
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Joe Yammine
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Gongxin Liu
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Xuwen Peng
- Department of Comparative Medicine, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, United States of America
| | - Zhilin Qu
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Gideon Koren
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
| | - Bum-Rak Choi
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America
- * E-mail:
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Ilter A, Kırış A, Kaplan Ş, Kutlu M, Şahin M, Erem C, Civan N, Kangül F. Atrial conduction times and left atrium mechanical functions in patients with active acromegaly. Endocrine 2015; 48:653-60. [PMID: 25022660 DOI: 10.1007/s12020-014-0348-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 06/25/2014] [Indexed: 11/26/2022]
Abstract
The aim of this study was to evaluate atrial electromechanical delay (EMD), P wave dispersion (Pwd), and left atrial (LA) mechanical functions in patients with active acromegaly. Twenty-three patients with active acromegaly and 27 age- and sex-matched controls were included in this study. All atrial electromechanical interval parameters (PA lateral, PA septum, PA tricuspid, interatrial EMD, intra-LA EMD, and intra-right atrial EMD) were measured from mitral lateral annulus, mitral septal annulus, and right ventricular tricuspid annulus by tissue Doppler imaging. LA volumes were measured by the disk method in the apical four-chamber view and were indexed to the body surface area. Mechanical function parameters of LA were calculated. Pwd was performed by 12-lead electrocardiograms. Atrial electromechanical intervals (PA lateral, PA septum, PA tricuspid, interatrial EMD, intra-LA EMD, and intra-right atrial EMD) and Pwd were similar between patients with acromegaly and control subjects (all p > 0.05). LA volumes (maximum, minimum, and presystolic) and LA mechanical functions were not significantly different between the groups (all p > 0.05). Additionally, serum levels of growth hormone and insulin-like growth factor-1 were not correlated with atrial electromechanical parameters and LA mechanical functions. Atrial electrical conduction times were not prolonged and LA mechanical functions were not impaired in patients with active acromegaly compared with controls. And the prevalence of supraventricular arrhythmia risk may not increase in this population.
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Affiliation(s)
- A Ilter
- Department of Cardiology, Kanuni Training and Research Hospital, Trabzon, Turkey,
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Bakirci EM, Demirtas L, Degirmenci H, Topcu S, Demirelli S, Hamur H, Buyuklu M, Akbas EM, Ozcicek A, Ozcicek F, Ceyhun G, Topal E. Relationship of the total atrial conduction time to subclinical atherosclerosis, inflammation and echocardiographic parameters in patients with type 2 diabetes mellitus. Clinics (Sao Paulo) 2015; 70:73-80. [PMID: 25789513 PMCID: PMC4351316 DOI: 10.6061/clinics/2015(02)01] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Revised: 10/13/2014] [Accepted: 11/12/2014] [Indexed: 01/20/2023] Open
Abstract
OBJECTIVES The aim of our study was to evaluate the total atrial conduction time and its relationship to subclinical atherosclerosis, inflammation and echocardiographic parameters in patients with type 2 diabetes mellitus. METHODS A total of 132 patients with type 2 diabetes mellitus (mean age 54.5 ± 9.6 years; 57.6% male) and 80 age- and gender-matched controls were evaluated. The total atrial conduction time was measured by tissue-Doppler imaging and the carotid intima-media thickness was measured by B-mode ultrasonography. RESULTS The total atrial conduction time was significantly longer in the patients with type 2 diabetes mellitus than in the control group (131.7 ± 23.6 vs. 113.1 ± 21.3, p<0.001). The patients with type 2 diabetes mellitus had significantly increased carotid intima-media thicknesses, neutrophil to lymphocyte ratios and high-sensitivity C-reactive protein levels than those of the controls. The total atrial conduction time was positively correlated with the high-sensitivity C-reactive protein level, neutrophil to lymphocyte ratio, carotid intima-media thickness and left atrial volume index and negatively correlated with the early diastolic velocity (Em), Em/late diastolic velocity (Am) ratio and global peak left atrial longitudinal strain. A multiple logistic regression analysis demonstrated that the neutrophil to lymphocyte ratio, carotid intima-media thickness and global peak left atrial longitudinal strain were independent predictors of the total atrial conduction time. CONCLUSIONS We suggest that subclinical atherosclerosis and inflammation may represent a mechanism related to prolonged total atrial conduction time and that prolonged total atrial conduction time and impaired left atrial myocardial deformation may be represent early subclinical cardiac involvement in patients with type 2 diabetes mellitus.
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Affiliation(s)
- Eftal Murat Bakirci
- Department of Cardiology, Faculty of Medicine, Erzincan University, Erzincan, Turkey
| | - Levent Demirtas
- Department of Internal Medicine, Faculty of Medicine, Erzincan University, Erzincan, Turkey
| | - Husnu Degirmenci
- Department of Cardiology, Faculty of Medicine, Erzincan University, Erzincan, Turkey
| | - Selim Topcu
- Department of Cardiology, Faculty of Medicine, Ataturk University, Erzurum, Turkey
| | - Selami Demirelli
- Department of Cardiology, Erzurum Education and Research Hospital, Erzurum, Turkey
| | - Hikmet Hamur
- Department of Cardiology, Faculty of Medicine, Erzincan University, Erzincan, Turkey
| | - Mutlu Buyuklu
- Department of Cardiology, Faculty of Medicine, Erzincan University, Erzincan, Turkey
| | - Emin Murat Akbas
- Department of Internal Medicine, Faculty of Medicine, Erzincan University, Erzincan, Turkey
| | - Adalet Ozcicek
- Department of Cardiology, Faculty of Medicine, Ataturk University, Erzurum, Turkey
| | - Fatih Ozcicek
- Department of Internal Medicine, Faculty of Medicine, Erzincan University, Erzincan, Turkey
| | - Gokhan Ceyhun
- Department of Cardiology, Faculty of Medicine, Erzincan University, Erzincan, Turkey
| | - Ergun Topal
- Department of Cardiology, Faculty of Medicine, Erzincan University, Erzincan, Turkey
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Nguyen BL, Capotosto L, Persi A, Placanica A, Rafique A, Piccirillo G, Gaudio C, Gang ES, Siegel RJ, Vitarelli A. Global and regional left ventricular strain indices in post-myocardial infarction patients with ventricular arrhythmias and moderately abnormal ejection fraction. Ultrasound Med Biol 2015; 41:407-417. [PMID: 25542492 DOI: 10.1016/j.ultrasmedbio.2014.09.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 09/15/2014] [Accepted: 09/19/2014] [Indexed: 06/04/2023]
Abstract
The aim of the study described here was to compare myocardial strains in ischemic heart patients with and without sustained ventricular tachycardia (VT) and moderately abnormal left ventricular ejection fraction (LVEF) to investigate which index could better predict VT on the basis of the analysis of global and regional left ventricular (LV) dysfunction. We studied 467 patients with previous myocardial infarction and LVEF >35%. Fifty-one patients had documented VT, and 416 patients presented with no VT. LV volumes and score index were obtained by 2-D echocardiography. Longitudinal, radial and circumferential strains were determined. Strains of the infarct, border and remote zones were also obtained. There were no differences in standard LV 2-D parameters between patients with and those without VT. Receiver operating characteristic values were -12.7% for global longitudinal strain (area under the curve [AUC] = 0.72), -4.8% for posterior-inferior wall circumferential strain (AUC = 0.80), 61 ms for LV mechanical dispersion (AUC = 0.84), -10.1% for longitudinal strain of the border zone (AUC = 0.86) and -9.2% for circumferential strain of the border zone (AUC = 0.89). In patients with previous myocardial infarction and moderately abnormal LVEF, peri-infarct circumferential strain was the strongest predictor of documented ventricular arrhythmias among all strain quantitative indices. Additionally, strain values from posterior-inferior wall infarctions had a higher association with arrhythmic events compared with global strain.
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Affiliation(s)
| | | | | | | | - Asim Rafique
- Cedars-Sinai Medical Center, Los Angeles, California, USA
| | | | | | - Eli S Gang
- Cedars-Sinai Medical Center, Los Angeles, California, USA
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Katsanos S, van Rosendael P, Kamperidis V, van der Kley F, Joyce E, Debonnaire P, Karalis I, Bax JJ, Marsan NA, Delgado V. Insights into new-onset rhythm conduction disorders detected by multi-detector row computed tomography after transcatheter aortic valve implantation. Am J Cardiol 2014; 114:1556-61. [PMID: 25245414 DOI: 10.1016/j.amjcard.2014.08.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 08/01/2014] [Accepted: 08/01/2014] [Indexed: 11/15/2022]
Abstract
New-onset rhythm conduction disorders are frequent after transcatheter aortic valve implantation (TAVI). Multidetector row computed tomography may shed light on the pathophysiology of rhythm conduction disorders in patients who undergo TAVI with the Edwards SAPIEN valve. A total of 94 patients (mean age 81 ± 7 years, 48% men) treated with TAVI with the Edwards SAPIEN valve who underwent pre- and post-TAVI multidetector row computed tomography were included. Patients with preexisting right bundle branch block or left bundle branch block (LBBB) and permanent pacemakers were excluded. Pacemaker implantation or new-onset LBBB at 1-month follow-up was the combined end point. Overall, 1 pacemaker was implanted, and 14 cases of new-onset LBBB were recorded. Among several clinical and multi-detector row computed tomographic variables, overexpansion of the transcatheter valve >15% of native annular area (odds ratio 5.277, 95% confidence interval 1.398 to 19.919, p = 0.014) and depth of frame into the left ventricular outflow tract (odds ratio 1.401, 95% confidence interval 1.066 to 1.770, p = 0.010) were independently related to the need for a pacemaker or new-onset LBBB. In conclusion, overexpansion of the transcatheter prosthesis by >15% of native aortic annular area and implantation depth of the frame into the left ventricular outflow tract were independently associated with the need for a pacemaker or new-onset LBBB in patients who underwent TAVI with the Edwards SAPIEN valve.
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Affiliation(s)
- Spyridon Katsanos
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands
| | | | - Vasileios Kamperidis
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Frank van der Kley
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Emer Joyce
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Philippe Debonnaire
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Ioannis Karalis
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Jeroen J Bax
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Nina Ajmone Marsan
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Victoria Delgado
- Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands.
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Takamine S, Fujiwara S, Shigeru M, Ito T, Kawai H, Shiotani H, Hirata KI. Relationship of decreased accumulation of (99m)Tc-tetrofosmin on myocardial single-photon emission computed tomography images between QRS duration in dilated cardiomyopathy patient with left bundle branch block. J Nucl Cardiol 2014; 21:1023-8. [PMID: 24942610 DOI: 10.1007/s12350-014-9923-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 05/09/2014] [Indexed: 11/26/2022]
Abstract
PURPOSE This study aimed to clarify the relationship between severity of conduction delay in the left ventricle and myocardial uptake of (99m)Tc-tetrofosmin (TF) in dilated cardiomyopathy (DCM) patients with left bundle branch block (LBBB). METHODS AND RESULTS Thirty-two DCM patients with LBBB underwent electrocardiography and (99m)Tc-TF myocardial single-photon emission computed tomography (SPECT). SPECT images were acquired at 30 min (early images) and 3 h (late images) after injection. We calculated the total defect score (TDS) using a 20-segment model with a 5-point scoring system. The TDS in early and late images was defined as the summed early score (SES) and summed late score (SLS), respectively. On early images, 29 of 32 patients (91%) had decreased tracer uptake in the septum. All patients showed a decreased tracer uptake in the septum on late images. A significant correlation was observed between TDS (both SES and SLS) and QRS duration, with SLS showing an excellent correlation (SES: r = 0.554, P < 0.001; SLS: r = 0.779, P < 0.0001). CONCLUSIONS These findings suggest that in DCM patients with LBBB, hypoperfusion and myocardial damage in the septum might occur in accordance with an increase in the QRS duration.
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Affiliation(s)
- Sachiko Takamine
- Division of Cardiovascular and Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan,
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Senol MG, Özmen N, Yasar H, Tekeli H, Özdağ F, Saraçoğlu M. P-wave dispersion doesn't increase in patients with epilepsy. Ideggyogy Sz 2014; 67:331-334. [PMID: 25518261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
AIM Epileptic seizures have occasionally been associated with cardiac conditions as atrioventricular blocks, long QT syndrome etc. P-wave dispersion (PWD), which is the difference between the longest (P max) and shortest P-wave duration (P min), is considered as a forerunner of atrial fibrillation. In this study, we investigated P-wave dispersion (PWD) in epileptic patients; based on the hypothesis that microthromboembolism may occur in atrial fibrillation. METHODS Seventy five patients with mixed types of epilepsy and 50 age and sex matched healthy individuals were included into the study. P max, P min and PWD values were calculated for each subject from an ECG. RESULTS The mean age of subjects in the epilepsy group and control group were similar (p>0.05). P max in patients with epilepsy was 125.1±0.7 ms, P min was 67.3±10.3 ms, and PWD was 57.6±8.3 ms while these values in the control group were 116.8±11.0 ms, 66.5±5.5 ms and 46.8±7.1 ms, respectively. There were no statistically significant difference between two groups (p>0.05). CONCLUSIONS PWD does not increase in patients with mixed types of epilepsy. Therefore we believe that microthromboembolism due to atrial fibrillation can't cause epileptic seizures in patients with no structural heart disease.
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Soltysinska E, Speerschneider T, Winther SV, Thomsen MB. Sinoatrial node dysfunction induces cardiac arrhythmias in diabetic mice. Cardiovasc Diabetol 2014; 13:122. [PMID: 25113792 PMCID: PMC4149194 DOI: 10.1186/s12933-014-0122-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 08/03/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The aim of this study was to probe cardiac complications, including heart-rate control, in a mouse model of type-2 diabetes. Heart-rate development in diabetic patients is not straight forward: In general, patients with diabetes have faster heart rates compared to non-diabetic individuals, yet diabetic patients are frequently found among patients treated for slow heart rates. Hence, we hypothesized that sinoatrial node (SAN) dysfunction could contribute to our understanding of the mechanism behind this conundrum and the consequences thereof. METHODS Cardiac hemodynamic and electrophysiological characteristics were investigated in diabetic db/db and control db/+ mice. RESULTS We found improved contractile function and impaired filling dynamics of the heart in db/db mice, relative to db/+ controls. Electrophysiologically, we observed comparable heart rates in the two mouse groups, but SAN recovery time was prolonged in diabetic mice. Adrenoreceptor stimulation increased heart rate in all mice and elicited cardiac arrhythmias in db/db mice only. The arrhythmias emanated from the SAN and were characterized by large RR fluctuations. Moreover, nerve density was reduced in the SAN region. CONCLUSIONS Enhanced systolic function and reduced diastolic function indicates early ventricular remodeling in obese and diabetic mice. They have SAN dysfunction, and adrenoreceptor stimulation triggers cardiac arrhythmia originating in the SAN. Thus, dysfunction of the intrinsic cardiac pacemaker and remodeling of the autonomic nervous system may conspire to increase cardiac mortality in diabetic patients.
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Qin Y, Li Q, Ingram P, Barber C, Liu Z, Witte RS. Ultrasound current source density imaging of the cardiac activation wave using a clinical cardiac catheter. IEEE Trans Biomed Eng 2014; 62:241-7. [PMID: 25122512 DOI: 10.1109/tbme.2014.2345771] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Ultrasound current source density imaging (UCSDI), based on the acoustoelectric (AE) effect, is a noninvasive method for mapping electrical current in 4-D (space + time). This technique potentially overcomes limitations with conventional electrical mapping procedures typically used during treatment of sustained arrhythmias. However, the weak AE signal associated with the electrocardiogram is a major challenge for advancing this technology. In this study, we examined the effects of the electrode configuration and ultrasound frequency on the magnitude of the AE signal and quality of UCSDI using a rabbit Langendorff heart preparation. The AE signal was much stronger at 0.5 MHz (2.99 μV/MPa) than 1.0 MHz (0.42 μV/MPa). Also, a clinical lasso catheter placed on the epicardium exhibited excellent sensitivity without penetrating the tissue. We also present, for the first time, 3-D cardiac activation maps of the live rabbit heart using only one pair of recording electrodes. Activation maps were used to calculate the cardiac conduction velocity for atrial (1.31 m/s) and apical (0.67 m/s) pacing. This study demonstrated that UCSDI is potentially capable of real-time 3-D cardiac activation wave mapping, which would greatly facilitate ablation procedures for treatment of arrhythmias.
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Affiliation(s)
- J S Carvalho
- Brompton Centre for Fetal Cardiology, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK; Fetal Medicine Unit, St George's Hospital, St George's University of London, London, SW17 0QT, UK.
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Xu ZX, Zhong JQ, Zhang W, Yue X, Rong B, Zhu Q, Zheng Z, Zhang Y. Atrial conduction delay predicts atrial fibrillation in paroxysmal supraventricular tachycardia patients after radiofrequency catheter ablation. Ultrasound Med Biol 2014; 40:1133-1137. [PMID: 24613637 DOI: 10.1016/j.ultrasmedbio.2014.01.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Revised: 12/23/2013] [Accepted: 01/06/2014] [Indexed: 06/03/2023]
Abstract
This study aimed to assess whether intra- and inter-atrial conduction delay could predict atrial fibrillation (AF) for paroxysmal supraventricular tachycardia (PSVT) patients after successful treatment by radiofrequency catheter ablation (RFCA). Echocardiography examination was performed on 524 consecutive PSVT patients (15 patients were excluded). Left atrial dimension, right atrial diameter and intra- and inter-atrial conduction delay were measured before ablation. Patients were divided into group A (n = 32): occurrence of AF after the ablation and group B (n = 477): remained in sinus rhythm during follow-up. Receiver operating characteristic (ROC) curve analysis was performed to estimate the predictive value of intra- and inter-atrial conduction delay. Both intra- and inter-atrial conduction delay were higher in group A than in group B (4.79 ± 0.30 msec vs. 4.56 ± 0.32 msec; 21.98 ± 1.32 msec vs. 20.01 ± 1.33; p < 0.05). Binary logistic regression analysis showed that intra- and inter-atrial conduction were significant influential factors for the occurrence of AF (odds ratio [OR] = 13.577, 95% confidence interval [CI], 3.469-48.914; OR = 2.569, 95% CI, 1.909-3.459, p < 0.05). The ROC cure analysis revealed that intra-atrial conduction delay ≥ 4.45 msec and inter-atrial conduction delay ≥ 20.65 were the most optimal cut-off value for predicting AF in PSVT patients after RFCA. In conclusion, this is the first study to show that the intra- and inter-atrial conduction delay could effectively predict AF in post-ablation PSVT patients.
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Affiliation(s)
- Zhen-Xing Xu
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, China
| | - Jing-Quan Zhong
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, China.
| | - Wei Zhang
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, China
| | - Xin Yue
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, China
| | - Bing Rong
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, China
| | - Qing Zhu
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, China
| | - Zhaotong Zheng
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, China
| | - Yun Zhang
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, China
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Plank G, Costa CM, Prassl AJ. Parametrization strategies for matching activation sequences in models of ventricular electrophysiology. Annu Int Conf IEEE Eng Med Biol Soc 2013; 2013:1534-1537. [PMID: 24109992 DOI: 10.1109/embc.2013.6609805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Driven by recent advances in medical imaging, image segmentation and numerical techniques computer models of ventricular electrophysiology account for increasingly finer levels of anatomical and biophysical detail. However, considering the large number of model parameters involved parametrization poses a major challenge. A minimum requirement in combined experimental and modeling studies which aim at making specific predictions on a case by case basis is to achieve good agreement in activation and repolarization sequences between model and experiment or patient data. In this study we propose basic techniques which aide in determining bidomain parameters to match ventricular activation sequences. Two specific aspects will be considered. First, conduction velocity in the ventricles is orthotropic and varies in space. An iterative parametrization algorithm is implemented which determines appropriate conductivities which yield prescribed velocities. Secondly, impulse propagation in the ventricles is initiated subendocardially at Purkinje-ventricular junctions, the terminal endings of Purkinje system (PS), and, thus, the PS plays a key role in determining the shape of activation wave fronts as reflected in the QRS complex of the electro-cardiogram (ECG). While ventricular models equipped with generic PS topologies match well with experimental observation in terms of epicardial breakthrough sites, predicted ECGs match poorly with known key ECG characteristics.
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Jensen B, Boukens BJD, Postma AV, Gunst QD, van den Hoff MJB, Moorman AFM, Wang T, Christoffels VM. Identifying the evolutionary building blocks of the cardiac conduction system. PLoS One 2012; 7:e44231. [PMID: 22984480 PMCID: PMC3439475 DOI: 10.1371/journal.pone.0044231] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 07/30/2012] [Indexed: 01/18/2023] Open
Abstract
The endothermic state of mammals and birds requires high heart rates to accommodate the high rates of oxygen consumption. These high heart rates are driven by very similar conduction systems consisting of an atrioventricular node that slows the electrical impulse and a His-Purkinje system that efficiently activates the ventricular chambers. While ectothermic vertebrates have similar contraction patterns, they do not possess anatomical evidence for a conduction system. This lack amongst extant ectotherms is surprising because mammals and birds evolved independently from reptile-like ancestors. Using conserved genetic markers, we found that the conduction system design of lizard (Anolis carolinensis and A. sagrei), frog (Xenopus laevis) and zebrafish (Danio rerio) adults is strikingly similar to that of embryos of mammals (mouse Mus musculus, and man) and chicken (Gallus gallus). Thus, in ectothermic adults, the slow conducting atrioventricular canal muscle is present, no fibrous insulating plane is formed, and the spongy ventricle serves the dual purpose of conduction and contraction. Optical mapping showed base-to-apex activation of the ventricles of the ectothermic animals, similar to the activation pattern of mammalian and avian embryonic ventricles and to the His-Purkinje systems of the formed hearts. Mammalian and avian ventricles uniquely develop thick compact walls and septum and, hence, form a discrete ventricular conduction system from the embryonic spongy ventricle. Our study uncovers the evolutionary building plan of heart and indicates that the building blocks of the conduction system of adult ectothermic vertebrates and embryos of endotherms are similar.
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Affiliation(s)
- Bjarke Jensen
- Department of Anatomy, Embryology & Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Department of Biological Sciences, Zoophysiology, Aarhus University, Aarhus, Denmark
| | - Bastiaan J. D. Boukens
- Department of Anatomy, Embryology & Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Alex V. Postma
- Department of Anatomy, Embryology & Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Quinn D. Gunst
- Department of Anatomy, Embryology & Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Maurice J. B. van den Hoff
- Department of Anatomy, Embryology & Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Antoon F. M. Moorman
- Department of Anatomy, Embryology & Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Tobias Wang
- Department of Biological Sciences, Zoophysiology, Aarhus University, Aarhus, Denmark
| | - Vincent M. Christoffels
- Department of Anatomy, Embryology & Physiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- * E-mail:
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van der Hulst AE, Roest AAW, Holman ER, Vliegen HW, Hazekamp MG, Bax JJ, Blom NA, Delgado V. Relation of prolonged tissue Doppler imaging-derived atrial conduction time to atrial arrhythmia in adult patients with congenital heart disease. Am J Cardiol 2012; 109:1792-6. [PMID: 22444731 DOI: 10.1016/j.amjcard.2012.01.401] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 01/30/2012] [Accepted: 01/30/2012] [Indexed: 11/17/2022]
Abstract
Atrial arrhythmia (AA) is common in adult patients with congenital heart disease (CHD). To enable the prevention of AA or its complications, timely identification of adult patients with CHD at risk of AA is crucial. Long total atrial activation times have been related to AA. Tissue Doppler imaging (TDI) permits noninvasive evaluation of the total atrial conduction time (PA-TDI duration). The present study evaluated the association between the PA-TDI duration and the development of AA in adult patients with CHD. A total of 223 adult patients with CHD were followed up for the occurrence of AA after PA-TDI duration assessment. The PA-TDI duration was defined as the interval from the onset of the P wave on the electrocardiogram to the peak of the A' wave at the lateral atrial wall on TDI tracings. Among the various clinical and echocardiographic parameters, the association between the PA-TDI duration and AA occurrence was investigated. The median follow-up was 39 months (interquartile range 21 to 57). A PA-TDI duration of ≥126 ms was associated with AA during follow-up (log-rank, p <0.001). On multivariate analysis, a PA-TDI duration >126 ms (hazard ratio 2.25, 95% confidence interval 1.21 to 4.19) and history of AA (hazard ratio 4.89, 95% confidence interval 2.75 to 8.71) were independently associated with the occurrence of AA. In conclusion, PA-TDI duration and a history of AA were independently associated with the occurrence of AA in adult patients with CHD. The PA-TDI duration is a useful tool to identify patients with CHD at risk of AA during follow-up.
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Stephenson RS, Boyett MR, Hart G, Nikolaidou T, Cai X, Corno AF, Alphonso N, Jeffery N, Jarvis JC. Contrast enhanced micro-computed tomography resolves the 3-dimensional morphology of the cardiac conduction system in mammalian hearts. PLoS One 2012; 7:e35299. [PMID: 22509404 PMCID: PMC3324466 DOI: 10.1371/journal.pone.0035299] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Accepted: 03/14/2012] [Indexed: 01/26/2023] Open
Abstract
The general anatomy of the cardiac conduction system (CCS) has been known for 100 years, but its complex and irregular three-dimensional (3D) geometry is not so well understood. This is largely because the conducting tissue is not distinct from the surrounding tissue by dissection. The best descriptions of its anatomy come from studies based on serial sectioning of samples taken from the appropriate areas of the heart. Low X-ray attenuation has formerly ruled out micro-computed tomography (micro-CT) as a modality to resolve internal structures of soft tissue, but incorporation of iodine, which has a high molecular weight, into those tissues enhances the differential attenuation of X-rays and allows visualisation of fine detail in embryos and skeletal muscle. Here, with the use of a iodine based contrast agent (I2KI), we present contrast enhanced micro-CT images of cardiac tissue from rat and rabbit in which the three major subdivisions of the CCS can be differentiated from the surrounding contractile myocardium and visualised in 3D. Structures identified include the sinoatrial node (SAN) and the atrioventricular conduction axis: the penetrating bundle, His bundle, the bundle branches and the Purkinje network. Although the current findings are consistent with existing anatomical representations, the representations shown here offer superior resolution and are the first 3D representations of the CCS within a single intact mammalian heart.
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Affiliation(s)
- Robert S. Stephenson
- Department of Musculoskeletal Biology, Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool, Merseyside, United Kingdom
| | - Mark R. Boyett
- Cardiovascular Research Group, School of Medicine, University of Manchester, Manchester, Greater Manchester, United Kingdom
| | - George Hart
- Department of Musculoskeletal Biology, Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool, Merseyside, United Kingdom
| | - Theodora Nikolaidou
- Cardiovascular Research Group, School of Medicine, University of Manchester, Manchester, Greater Manchester, United Kingdom
| | - Xue Cai
- Cardiovascular Research Group, School of Medicine, University of Manchester, Manchester, Greater Manchester, United Kingdom
| | - Antonio F. Corno
- Prince Salman Heart Center, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - Nelson Alphonso
- Alder Hey Children’s NHS Foundation Trust, Liverpool, Merseyside, United Kingdom
| | - Nathan Jeffery
- Department of Musculoskeletal Biology, Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool, Merseyside, United Kingdom
| | - Jonathan C. Jarvis
- Department of Musculoskeletal Biology, Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool, Merseyside, United Kingdom
- * E-mail:
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Abstract
BACKGROUND Arterial stiffness is strongly predictive for cardiovascular events in hypertensive individuals and it may increase the risk of stroke. This study was designed to evaluate the possible relationship between arterial stiffness and atrial electromechanical delay and P wave dispersion (PWD), as determinants of AF risk. MATERIALS AND METHODS The study included 75 hypertensive patients and 45 healthy control subjects. Atrial electromechanical coupling (time interval from the onset of P wave on ECG to the beginning of A wave with tissue Doppler echocardiography [PA]), intraatrial and interatrial electromechanical delay (EMD) and PWD were measured. Stiffness index β & PWV was measured to assess the arterial stiffness. RESULTS The interatrial EMD and PWD were prolonged in hypertensive patients compared to controls (p<0.01 for both), There was increased arterial stiffness (PWV and stiffness index β) in hypertensive patients compared to controls (6.43 ± 1.73 vs. 4.8 ± 1.6 m/sec & 4.9 ± 2.8 vs. 2.63 ± 1.2, p<0.01 for both). By multivariate analysis; PWV and Stiffness index β were independently correlated with interatrial EMD (B ± SE=0.42 ± 1.87, B ± SE=0.39 ± 0.21 p<0.01 for both) and PWD (B ± SE=0.37 ± 1.93, p<0.01, B ± SE=0.25 ± 0.18, p<0.05 respectively). CONCLUSION In hypertensive patients arterial stiffness indexes increased and showed a significant correlation with interatrial EMD and PWD independent of other variables. Further research is needed to determine whether interventions that reduce arterial stiffness will limit the growing incidence of AF.
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Scharf C, Krasniqi N, Hellermann J, Rahn M, Sütsch G, Brunckhorst C, Duru F. Electrical activation in the coronary sinus branches as a guide to cardiac resynchronisation therapy: rationale for a coordinate system. PLoS One 2011; 6:e19914. [PMID: 21857896 PMCID: PMC3152548 DOI: 10.1371/journal.pone.0019914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 04/20/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND For successful cardiac resynchronisation therapy (CRT) a spatial and electrical separation of right and left ventricular electrodes is essential. The spatial distribution of electrical delays within the coronary sinus (CS) tributaries has not yet been identified. OBJECTIVE Electrical delays within the CS are described during sinus rhythm (SR) and right ventricular pacing (RVP). A coordinate system grading the mitral ring from 0° to 360° and three vertical segments is proposed to define the lead positions irrespective of individual CS branch orientation. METHODS In 13 patients undergoing implantation of a CRT device 6±2.5, (median 5) lead positions within the CS were mapped during SR and RVP. The delay to the onset and the peak of the local signal was measured from the earliest QRS activation or the pacing spike. Fluoroscopic positions were compared to localizations on a nonfluoroscopic electrode imaging system. RESULTS During SR, electrical delays in the CS were inhomogenous in patients with or without left bundle branch block (LBBB). During RVP, the delays increased by 44±32 ms (signal onset from 36±33 ms to 95±30 ms; p<0.001, signal peak from 105±44 ms to 156±30 ms; p<0.001). The activation pattern during RVP was homogeneous and predictable by taking the grading on the CS ring into account: (% QRS) = 78-0.002 (grade-162)(2), p<0.0001. This indicates that 78% of the QRS duration can be expected as a maximum peak delay at 162° on the CS ring. CONCLUSION Electrical delays within the CS vary during SR, but prolong and become predictable during RVP. A coordinate system helps predicting the local delays and facilitates interindividual comparison of lead positions irrespective of CS branch anatomy.
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Affiliation(s)
- Christoph Scharf
- Division of Pacing and Electrophysiology, Clinic for Cardiology, Cardiovascular Center, University Hospital Zurich, Zurich, Switzerland.
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Bish LT, Yarchoan M, Sleeper MM, Gazzara JA, Morine KJ, Acosta P, Barton ER, Sweeney HL. Chronic losartan administration reduces mortality and preserves cardiac but not skeletal muscle function in dystrophic mice. PLoS One 2011; 6:e20856. [PMID: 21731628 PMCID: PMC3120761 DOI: 10.1371/journal.pone.0020856] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 05/10/2011] [Indexed: 11/19/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a degenerative disorder affecting skeletal and cardiac muscle for which there is no effective therapy. Angiotension receptor blockade (ARB) has excellent therapeutic potential in DMD based on recent data demonstrating attenuation of skeletal muscle disease progression during 6–9 months of therapy in the mdx mouse model of DMD. Since cardiac-related death is major cause of mortality in DMD, it is important to evaluate the effect of any novel treatment on the heart. Therefore, we evaluated the long-term impact of ARB on both the skeletal muscle and cardiac phenotype of the mdx mouse. Mdx mice received either losartan (0.6 g/L) (n = 8) or standard drinking water (n = 9) for two years, after which echocardiography was performed to assess cardiac function. Skeletal muscle weight, morphology, and function were assessed. Fibrosis was evaluated in the diaphragm and heart by Trichrome stain and by determination of tissue hydroxyproline content. By the study endpoint, 88% of treated mice were alive compared to only 44% of untreated (p = 0.05). No difference in skeletal muscle morphology, function, or fibrosis was noted in losartan-treated animals. Cardiac function was significantly preserved with losartan treatment, with a trend towards reduction in cardiac fibrosis. We saw no impact on the skeletal muscle disease progression, suggesting that other pathways that trigger fibrosis dominate over angiotensin II in skeletal muscle long term, unlike the situation in the heart. Our study suggests that ARB may be an important prophylactic treatment for DMD-associated cardiomyopathy, but will not impact skeletal muscle disease.
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Affiliation(s)
- Lawrence T Bish
- Department of Physiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America.
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45
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Lábrová R. [A modification of the spectrum of supraventricular tachycardias indicated for catheter ablation]. Vnitr Lek 2011; 57:523-528. [PMID: 21751535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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Abstract
Cardiac conduction abnormalities remain a major cause of death and disability worldwide. However, as of today, there is no standard clinical imaging modality that can noninvasively provide maps of the electrical activation. In this paper, electromechanical wave imaging (EWI), a novel ultrasound-based imaging method, is shown to be capable of mapping the electromechanics of all four cardiac chambers at high temporal and spatial resolutions and a precision previously unobtainable in a full cardiac view in both animals and humans. The transient deformations resulting from the electrical activation of the myocardium were mapped in 2D and combined in 3D biplane ventricular views. EWI maps were acquired during five distinct conduction configurations and were found to be closely correlated to the electrical activation sequences. EWI in humans was shown to be feasible and capable of depicting the normal electromechanical activation sequence of both atria and ventricles. This validation of EWI as a direct, noninvasive, and highly translational approach underlines its potential to serve as a unique imaging tool for the early detection, diagnosis, and treatment monitoring of arrhythmias through ultrasound-based mapping of the transmural electromechanical activation sequence reliably at the point of care, and in real time.
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Affiliation(s)
- Jean Provost
- Department of Biomedical Engineering, Columbia University, New York, NY 10027; and
| | - Wei-Ning Lee
- Department of Biomedical Engineering, Columbia University, New York, NY 10027; and
| | - Kana Fujikura
- Department of Radiology, Columbia University, New York, NY 10032
| | - Elisa E. Konofagou
- Department of Biomedical Engineering, Columbia University, New York, NY 10027; and
- Department of Radiology, Columbia University, New York, NY 10032
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Cameron BM, Rettmann ME, Holmes DR, Robb RA. Fast adaptation of pre-operative patient specific models to real-time intra-operative volumetric data streams. Stud Health Technol Inform 2011; 163:99-104. [PMID: 21335770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Image-guided catheter ablation therapy is becoming an increasingly popular treatment option for atrial fibrillation. Successful treatment relies on accurate guidance of the treatment catheter. Integration of high-resolution, pre-operative data with electrophysiology data and positional data from tracked catheters improves targeting, but lacks the means to monitor changes in the atrial wall. Intra-operative ultrasound provides a method for imaging the atrial wall, but the real-time, dynamic nature of the data makes it difficult to seamlessly integrate with the static pre-operative patient-specific model. In this work, we propose a technique which uses a self-organizing map (SOM) for dynamically adapting a pre-operative model to surface patch data. The surface patch would be derived from a segmentation of the anatomy in a real-time, intra-operative ultrasound data stream. The method is demonstrated on two regular geometric shapes as well as data simulated from a real, patient computed tomography dataset.
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Affiliation(s)
- Bruce M Cameron
- Mayo Clinic College of Medicine, Biomedical Imaging Resource, Rochester MN, USA
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Strehlow SL, Pathak B, Goodwin TM, Perez BM, Ebrahimi M, Lee RH. The mechanical PR interval in fetuses of women with intrahepatic cholestasis of pregnancy. Am J Obstet Gynecol 2010; 203:455.e1-5. [PMID: 20684945 DOI: 10.1016/j.ajog.2010.05.035] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 03/23/2010] [Accepted: 05/19/2010] [Indexed: 11/28/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate the fetal mechanical PR interval in intrahepatic cholestasis of pregnancy (ICP). STUDY DESIGN Fetal echocardiography was performed for women with ICP and control subjects. Clinical characteristics, total bile acids, and liver profile tests were compared between groups. RESULTS Fourteen women with ICP and 7 control subjects were enrolled. Total bile acids (28.3 vs 6.2 μmol/L; P < .001), aspartate aminotransferase (53 vs 23 IU/L; P = .002), alanine aminotransferase (63 vs 19 IU/L; P = .002), and the PR interval (124 vs 110 msec; P = .006) were significantly higher in fetuses with ICP than in control fetuses. On multivariable linear regression analysis, only the presence of ICP was associated significantly with an increase in the PR interval (95% confidence interval, 4-24 msec; P = .01). CONCLUSION The fetal cardiac conduction system is altered in ICP. Further investigation is needed to determine whether fetal echocardiography can help to predict which fetuses are at risk for death that is associated with ICP.
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Affiliation(s)
- Stacy L Strehlow
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, LAC+USC Medical Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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Mivelaz Y, Raboisson MJ, Abadir S, Sarquella-Brugada G, Fournier A, Fouron JC. Ultrasonographic diagnosis of delayed atrioventricular conduction during fetal life: a reliability study. Am J Obstet Gynecol 2010; 203:174.e1-7. [PMID: 20435283 DOI: 10.1016/j.ajog.2010.02.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 10/30/2009] [Accepted: 02/10/2010] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The objective of the study was to evaluate the reliability of the 2 most commonly used ultrasonographic approaches for monitoring fetal atrioventricular conduction time (AVCT): (1) superior vena cava/ascending aorta (SVC/AA), and (2) left ventricular inflow/outflow tract (LVI/O) Doppler recordings. STUDY DESIGN Echographic studies from fetuses followed up for first-degree atrioventricular block (AVB-1) between 1998 and 2008 were reviewed. The ability to identify atrial contractions in the same fetuses by the SVC/AA and LVI/O approaches was analyzed. RESULTS Sixty-six studies of 13 fetuses with AVB-1 were available. Atrial contractions were visible in all SVC/AA studies. With the LVI/O approach, atrial contractions could not be identified in 26 studies (39%). AVCT delay was significantly greater in the nonidentifiable compared with the identifiable atrial contraction group (P < .001). Differences in heart rate and gestational age were not significant. CONCLUSION The LVI/O is unsuitable for prenatal screening of conduction system anomalies.
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Affiliation(s)
- Yvan Mivelaz
- Cardiology Division, Fetal Cardiology Unit, Department of Pediatrics, Centre Hospitalier Universitaire Sainte-Justine, University of Montreal, Montreal, QC, Canada
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Abstract
OBJECTIVE The fetal mechanical PR interval obtained via pulsed Doppler has previously been demonstrated to correlate with electrocardiographic PR interval measured in the neonate. We sought to further analyze the influence of fetal heart rate and gestational age upon the fetal mechanical PR interval. METHODS We searched our database for mechanical PR intervals, which were obtained during fetal echocardiography performed in our antenatal diagnostic unit. We included fetuses with a normal cardiac structural survey. The mechanical PR interval is measured from the A wave of the mitral valve to the beginning of ventricular systole corresponding to the opening of the aortic valve. Linear regression curves were generated to examine the correlation of mechanical PR interval with gestational age and fetal heart rate. Analysis of variance was used to compare the mean variation across three gestational age groups: 17-21.9 weeks (n = 24), 22-25.9 weeks (n = 52) and 26-38 weeks (n = 20). RESULTS Mechanical PR intervals were measured in 96 fetuses with normal fetal echocardiography. The mechanical PR interval was 123.9 +/- 10.3 ms (mean +/- SD), with a range of 90-150 ms. Linear regression curves correlating mechanical PR interval with fetal heart rate and gestational age demonstrated a flat slope with R2 = 0.016, p = 0.22 and R2 = 0.0004, p = 0.85, respectively. The mechanical PR interval measured over the three gestational ages was as follows (mean +/- SD): 122.3 +/- 10.5 ms for 17-21.9 weeks; 125.0 +/- 9.6 ms for 22-25.9 weeks; and 123.1 +/- 11.9 ms for 26-38 weeks. Analysis of variance revealed no difference among the mechanical PR interval means measured over the three gestational age groups (p = 0.53). CONCLUSIONS Fetal mechanical PR interval ranges from 90 to 150 ms in fetuses with sonographically normal fetal cardiac structure and rate. The mechanical PR interval appears to be independent of gestational age and fetal heart rate.
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Affiliation(s)
- A D Bolnick
- Department of Obstetrics and Gynecology, University of Connecticut Health Center, Farmington, Connecticut, USA
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