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Bi ventricular pacing

Hiro Yamasaki, Daniel Lustgarten, Jeffrey Cerkvenik, David Birnie, Maurizio Gasparini, Kathy Lia-Fun Lee, Yukio Sekiguchi, Niraj Varma, Bernd Lemke, Randall C Starling, Kazutaka Aonuma
BACKGROUND: Adaptive cardiac resynchronization therapy (aCRT) is a dynamic optimization algorithm which paces only the left ventricle (LV) when atrio-ventricular (AV) conduction is normal, thus reducing right ventricular (RV) pacing. However, the impact of QRS duration on aCRT efficacy remains uncertain. We examined whether QRS duration impacts aCRT effectiveness in patients with left bundle branch block (LBBB) and preserved AV conduction. METHODS: Randomized patients in the Adaptive CRT trial, which enrolled NYHA III/IV patients, were used in this analysis...
April 12, 2017: International Journal of Cardiology
Qingzhi Luo, Qi Jin, Ning Zhang, Yanxin Han, Yilong Wang, Shangwei Huang, Changjian Lin, Tianyou Ling, Kang Chen, Wenqi Pan, Liqun Wu
BACKGROUND: The objective of this study was to detect differences in the distribution of the left and right ventricle (LV & RV) activation rate (AR) during short-duration ventricular fibrillation (SDVF, <1 min) and long-duration ventricular fibrillation VF (LDVF, >1 min) in normal and heart failure (HF) canine hearts. METHODS: Ventricular fibrillation (VF) was electrically induced in six healthy dogs (control group) and six dogs with right ventricular pacing-induced congestive HF (HF group)...
April 13, 2017: BMC Cardiovascular Disorders
Shinya Yamada, Li-Wei Lo, Yu-Hui Chou, Wei-Lun Lin, Shih-Lin Chang, Yenn-Jiang Lin, Shih-Ann Chen
BACKGROUND: Heart failure (HF) causes atrial remodeling and increases the incidence of atrial fibrillation (AF). Renal denervation (RDN) has been shown to decrease the development of AF. This study aimed to identify the effects of RDN on the atrial arrhythmogenic substrates in HF. METHODS: Rabbits were classified into four groups: control (n=9), RDN (n=10), HF (n=6) and HF-RDN (n=9). Surgical and chemical RDN was approached through bilateral retroperitoneal flank incisions in RDN and HF-RDN...
May 15, 2017: International Journal of Cardiology
Antonio Hernández-Madrid, Domenico Facchin, Ruth Nicholson Klepfer, Subham Ghosh, Roberto Matía, Javier Moreno, Alessandro Locatelli
BACKGROUND: A high percentage of biventricular (BiV) or left ventricular (LV) pacing in cardiac resynchronization therapy (CRT) devices has been associated with superior clinical outcomes. However, the percent ventricular (%V) pacing reported by CRT devices simply indicates the number of paces the device has delivered and not the proportion of pacing that has captured the LV effectively. OBJECTIVE: The purpose of this study was to determine whether a beat-by-beat evaluation of effective pacing would provide a more accurate evaluation of CRT delivery...
April 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Ammar M Killu, Jae-Yoon Park, Jaskanwal D Sara, David O Hodge, Bernard J Gersh, Rick A Nishimura, Samuel J Asirvatham, Christopher J McLeod
AIMS: A dilated/end-stage phase of hypertrophic cardiomyopathy (HCM) is rare but well-recognized. The role for cardiac resynchronization therapy (CRT) in this subset of patients remains unexplored. We aimed to clarify the impact of bi-ventricular pacing CRT in dilated/end-stage HCM. METHODS AND RESULTS: The Mayo Clinic HCM database was interrogated to identify patients with ejection fraction (EF) <50% and CRT. Control subjects were identified in 1:1 manner...
December 23, 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
Aamir Sofi, Pugazhendhi Vijayaraman, S Serge Barold, Bengt Herweg
Biventricular pacing has occasionally been associated with ventricular proarrhythmia, which at times can be refractory to conventional antiarrhythmic drug therapy and ablative intervention. Recently, permanent His-bundle pacing has emerged as a reasonable alternative to right ventricular and biventricular pacing. In addition, by maintaining the physiologic pattern of ventricular electrical activation, it is less likely to be arrhythmogenic. We report the use of permanent His-bundle pacing to manage ventricular proarrhythmia that developed after initiation of biventricular pacing and was unresponsive to antiarrhythmic and ablative therapy...
December 20, 2016: Pacing and Clinical Electrophysiology: PACE
Pedro Marques, Miguel Nobre Menezes, Gustavo Lima da Silva, Ana Bernardes, Andreia Magalhães, Nuno Cortez-Dias, Luís Carpinteiro, João de Sousa, Fausto J Pinto
INTRODUCTION AND AIM: Multi-site pacing is emerging as a new method for improving response to cardiac resynchronization therapy (CRT), but has been little studied, especially in patients with atrial fibrillation. We aimed to assess the effects of triple-site (Tri-V) vs. biventricular (Bi-V) pacing on hemodynamics and QRS duration. METHODS: This was a prospective observational study of patients with permanent atrial fibrillation and ejection fraction <40% undergoing CRT implantation (n=40)...
June 2016: Portuguese Journal of Cardiology: An Official Journal of the Portuguese Society of Cardiology
Adam Goldberg, Kenya Kusunose, Salima Qamruddin, L Leonardo Rodriguez, Todor N Mazgalev, Brian P Griffin, David R Van Wagoner, Youhua Zhang, Zoran B Popović
BACKGROUND: Our aim was to assess how atrial fibrillation (AF) induction, chronicity, and RR interval irregularity affect left atrial (LA) function and size in the setting of underlying heart failure (HF), and to determine whether AF effects can be mitigated by vagal nerve stimulation (VNS). METHODS: HF was induced by 4-weeks of rapid ventricular pacing in 24 dogs. Subsequently, AF was induced and maintained by atrial pacing at 600 bpm. Dogs were randomized into control (n = 9) and VNS (n = 15) groups...
2016: PloS One
Francisco Sahli Costabal, Daniel E Hurtado, Ellen Kuhl
The Purkinje network is an integral part of the excitation system in the human heart. Yet, to date, there is no in vivo imaging technique to accurately reconstruct its geometry and structure. Computational modeling of the Purkinje network is increasingly recognized as an alternative strategy to visualize, simulate, and understand the role of the Purkinje system. However, most computational models either have to be generated manually, or fail to smoothly cover the irregular surfaces inside the left and right ventricles...
August 16, 2016: Journal of Biomechanics
Sophie Bruge, Antoine Simon, Mathieu Lederlin, Julian Betancur, Alfredo Hernandez, Erwan Donal, Christophe Leclercq, Mireille Garreau
Cardiac Resynchronization Therapy (CRT) has been validated as an efficient treatment for selected patients suffering from heart failure with cardiac dyssynchrony. In case of bi-ventricular stimulation, the response to the therapy may be improved by an optimal choice of the left ventricle (LV) pacing sites. The characterization of LV properties to select the best candidate sites and to precise their access modes would be useful for the clinician in pre- and per-operative stages. For that purpose, we propose a new pre-operative analysis solution integrating previously developed multi-modal data registration methods and a new segmentation process of their coronary venous access...
2015: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Oleg E Osadchii
OBJECTIVES: Flecainide is class Ic antiarrhythmic agent that was found to increase the risk of sudden cardiac death. Arrhythmic responses to flecainide could be precipitated by exercise, suggesting a role played by inappropriate rate adaptation of ventricular repolarization. This study therefore examined flecainide effect on adaptation of the QT interval and ventricular action potential duration (APD) to abrupt reductions of the cardiac cycle length. DESIGN: ECG and ventricular epicardial and endocardial monophasic APD were recorded in isolated, perfused guinea-pig heart preparations upon a sustained cardiac acceleration (rapid pacing for 30 s), and following a single perturbation of the cycle length evoked by extrasystolic stimulation...
2016: Scandinavian Cardiovascular Journal: SCJ
Xuesi Chen, Xingxing Chen, Junhua Cheng, Jun Hong, Cheng Zheng, Jinglin Zhao, Jin Li, Jiafeng Lin
OBJECTIVE: This project is designed to explore the potential role of cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) in cardiac electrical remodeling induced by pacing at different ventricular positions in dogs. METHODS: An animal model by implanting the pacemakers in beagles was established. According to the different pacing positions, the animals were divided into 4 groups:conditional control group (n=6), left ventricle pacing group (n=6), right ventricle pacing group (n=6) and bi-ventricle pacing group (n=6)...
April 2015: Zhonghua Xin Xue Guan Bing za Zhi
Satsuki Yamada, D Kent Arrell, Almudena Martinez-Fernandez, Atta Behfar, Garvan C Kane, Carmen M Perez-Terzic, Ruben J Crespo-Diaz, Robert J McDonald, Saranya P Wyles, Jelena Zlatkovic-Lindor, Timothy J Nelson, Andre Terzic
BACKGROUND: Cardiac resynchronization therapy using bi-ventricular pacing is proven effective in the management of heart failure (HF) with a wide QRS-complex. In the absence of QRS prolongation, however, device-based resynchronization is reported unsuitable. As an alternative, the present study tests a regenerative cell-based approach in the setting of narrow QRS-complex HF. METHODS AND RESULTS: Progressive cardiac dyssynchrony was provoked in a chronic transgenic model of stress-triggered dilated cardiomyopathy...
May 11, 2015: Journal of the American Heart Association
Gianni Pedrizzetti, Alfonso R Martiniello, Valter Bianchi, Antonio D'Onofrio, Pio Caso, Giovanni Tonti
Hemodynamic forces represent an epigenetic factor during heart development and are supposed to influence the pathology of the grown heart. Cardiac blood motion is characterized by a vortical dynamics, and it is common belief that the cardiac vortex has a role in disease progressions or regression. Here we provide a preliminary demonstration about the relevance of maladaptive intra-cardiac vortex dynamics in the geometrical adaptation of the dysfunctional heart. We employed an in vivo model of patients who present a stable normal heart function in virtue of the cardiac resynchronization therapy (CRT, bi-ventricular pace-maker) and who are expected to develop left ventricle remodeling if pace-maker was switched off...
January 21, 2015: Journal of Biomechanics
Kelvin C Lau, J William Gaynor, Stephanie M Fuller, Karen A Smoots, Maully J Shah
BACKGROUND: Multiple cardiac operations and resultant myocardial scarring have been implicated in the overall reduced performance of epicardial pacing systems in patients with congenital heart disease (CHD). OBJECTIVE: The aim of the study is to evaluate long-term permanent epicardial pacing lead survival in patients with CHD who had epicardial lead placement in association with surgical repair or palliation. METHODS: A retrospective review of patients who had implantation of epicardial pacing systems between January 1984 and June 2010 was conducted...
March 2015: Heart Rhythm: the Official Journal of the Heart Rhythm Society
Yongle Chen, Leilei Cheng, Haohua Yao, Haiyan Chen, Yongshi Wang, Weipeng Zhao, Cuizhen Pan, Xianhong Shu
Evidence-based criteria for applying cardiac resynchronization therapy (CRT) in patients with ischemic cardiomyopathy are still scarce. The aim of the present study was to evaluate the predictive value of real-time myocardial contrast echocardiography (RT-MCE) in a preclinical canine model of ischemic cardiomyopathy who received CRT. Ischemic cardiomyopathy was produced by ligating the first diagonal branch in 20 beagles. Dogs were subsequently divided into two groups that were either treated with bi-ventricular pacing (CRT group) or left untreated (control group)...
2014: PloS One
Amit Livneh, Eitan Kimmel, Andrew R Kohut, Dan Adam
Ultrasound has been shown to produce Premature Ventricular Contractions (PVC's). Two clinical applications in which acute cardiac pacing by ultrasound may be valuable are: (1) preoperative patient screening in cardiac resynchronization therapy surgery; (2) Emergency life support, following an event of sudden death, caused by cardiac arrest. Yet, previously the demonstrated mean success rate of extra-systole induction by High Intensity Focused Ultrasound (HIFU) in rats is below 4.5% (Miller et al., 2011). This stands in contrast to previous work in rats using ultrasound (US) and ultrasound contrast agents (UCAs), where success rates of close to 100% were reported (Rota et al...
August 2014: Progress in Biophysics and Molecular Biology
Juan Manuel Lange, Hector Manzolillo, Jorge Parras, Domingo Pozzer, Ignacio Reyes, Rolando Pantich
OBJECTIVE: To determine in patients with normal ejection fraction, undergoing permanent VVI pacing, if medial septal stimulation has lower dyssynchrony than apical stimulation assessed by echocardiography. METHOD: A prospective trial, 19 patients>70 years old, scheduled for VVI pacemaker implantation for complete degenerative atrioventricular block, ventricular frequency<50beat per minute and ejection fraction≥45%. Patients with atrial fibrillation, heart failure, left bundle branch block and QRS durations longer than 120milliseconds in surface electrocardiogram with sinus rhythm were excluded...
July 2014: Archivos de Cardiología de México
Salah S Al-Zaiti, James A Fallavollita, John M Canty, Mary G Carey
OBJECTIVE: This study evaluated the prognostic value of electrocardiogram (ECG)-based predictors in the primary prevention of sudden cardiac arrest (SCA) among ischemic cardiomyopathy patients with depressed left ventricular ejection fraction (LVEF ≤35%). BACKGROUND: The prediction of cause-specific mortality in high-risk patients offers the potential for targeting specific therapies (i.e., implantable cardioverter-defibrillator [ICD]). METHODS: Subjects were recruited from the Prediction of Arrhythmic Events with Positron Emission Tomography (PAREPET) study...
November 2014: Heart & Lung: the Journal of Critical Care
Erik R Larson, John E Porterfield, Sandeep Sagar, Juan Marmol-Velez, Manoj Panday, Daniel Escobedo, Joel Michalek, Yongjian Ouyang, Jonathan W Valvano, John A Pearce, Marc D Feldman
BACKGROUND: Implantable cardioverter-defibrillators monitor intracardiac electrograms (EGMs) to discriminate between ventricular and supraventricular tachycardias. The incidence of inappropriate shocks remains high because of misclassification of the tachycardia in an otherwise hemodynamically stable individual. Coupling EGMs with an assessment of left ventricular (LV) stroke volume (SV) could help in gauging hemodynamics during an arrhythmia and reducing inappropriate shocks. OBJECTIVE: The purpose of this study was to use the admittance method to accurately derive LV SV...
November 2014: Heart Rhythm: the Official Journal of the Heart Rhythm Society
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