Biventricular Pacing (biventricular + pacing)

Distribution by Scientific Domains


Selected Abstracts


Feasibility of Biventricular Pacing in Patients With Recent Myocardial Infarction: Impact on Ventricular Remodeling

CONGESTIVE HEART FAILURE, Issue 1 2007
Eugene S. Chung MD
To test the hypothesis that biventricular pacing after a myocardial infarction with reduced ejection fraction can attenuate left ventricular (LV) remodeling, the authors studied 18 patients (myocardial infarction within 30,45 days, ejection fraction ,30%, narrow QRS) randomized to biventricular therapy (biventricular therapy + defibrillator) (biventricular group) or implantable cardioverter-defibrillator alone (control group). At 1, 6, and 12 months, there were no differences in functional or clinical parameters (New York Heart Association, quality of life, 6-minute walk). Twelve-month LV volume remained stable in the biventricular group, but increased in the control group (median LV end-diastolic volume increase, 6.5 mL in biventricular vs 35 mL in control; P=.03; median LV end-diastolic volume decrease, 5.5 mL in biventricular vs 30.5-mL increase in control; P=.11). Biventricular therapy also prevented an increase in sphericity index at 12 months (median, ,2% in biventricular vs 37% in control; P=.06). Delivery of biventricular therapy early after myocardial infarction appears safe and feasible and may attenuate subsequent LV dilation. [source]


Echocardiographic Features of Patients With Heart Failure Who May Benefit From Biventricular Pacing

ECHOCARDIOGRAPHY, Issue 3 2003
Amgad N. Makaryus
Background: Recent studies suggest that cardiac resynchronization therapy through biventricular pacing (BVP) may be a promising new treatment for patients with advanced congestive heart failure (CHF). This method involves implantation of pacer leads into the right atrium (RA), right ventricle (RV), and coronary sinus (CS) in patients with ventricular dyssynchrony as evidenced by a bundle branch block pattern on electrocardiogram (ECG). Clinical trials are enrolling stable patients with ejection fractions (EF) , 35%, left ventricular end-diastolic diameters (LVIDd) , 54 mm, and QRS duration ,140 msec. We compared echocardiography features of these patients (group 1) with other patients with EF , 35%, LVIDd , 54 mm, and QRS < 140 msec (group 2 = presumably no dyssynchrony). Methods: Nine hundred fifty-one patients with CHF, LVID 54 mm, EF 35% by echocardiography were retrospectively evaluated. One hundred forty-five patients remained after those with primary valvular disease, prior pacing systems, or chronic atrial arrhythmias were excluded. From this group of 145 patients, a subset of 50 randomly selected patients were further studied (25 patients [7 females, 18 males] from group 1, and 25 patients [7 females, 18 males] from group 2). Mean age group 1 = 75 years old, mean age group 2 = 67 years old. Mean QRS group 1 = 161 msec, mean QRS group 2 = 110 msec. Each group was compared for presence of paradoxical septal motion, atrial and ventricular chamber sizes, LV mass, LVEF, and RV systolic function. Results: Of the initial group of 951 patients, 145 (15%) met inclusion criteria. In the substudy, 20/25 (80%) of group l and 7/25 (28%) of group 2 subjects had paradoxical septal motion on echo (Fisher's exact test, P = 0.0005). The t-tests performed on the other echocardiography variables demonstrated no differences in chamber size, function, or LV mass. Conclusions: Cardiac resynchronization therapy with BVP appears to target a relatively small population of our advanced CHF patients (15% or less). Although increasing QRS duration on ECG is associated with more frequent paradoxical septal motion on echo, it is not entirely predictive. Paradoxical septal motion on echo may therefore be more sensitive at identifying patients who respond to BVP. Further prospective studies are needed. (ECHOCARDIOGRAPHY, Volume 20, April 2003) [source]


Biventricular Pacing and Left Ventricular Pacing in Heart Failure:

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2004
Similar Hemodynamic Improvement Despite Marked Electromechanical Differences
Introduction: We conducted an acute echocardiographic study comparing hemodynamic and ventricular dyssynchrony parameters during left ventricular pacing (LVP) and biventricular pacing (BVP). We sought to clarify the mechanisms responsible for similar hemodynamic improvement despite differences in electrical activation. Methods and Results: Thirty-three patients underwent echocardiography prior to implantation with a multisite pacing device (spontaneous rhythm [SR]) and 2 days after implantation (BVP and LVP). Interventricular dyssynchrony (pulsed-wave Doppler), extent of myocardium displaying delayed longitudinal contraction (%DLC; tissue tracking), and index of LV dyssynchrony (pulsed-wave tissue Doppler imaging) were assessed. Compared to SR, BVP and LVP caused similar significant improvement of cardiac output (LVP: 3.2 ± 0.5, BVP: 3.1 ± 0.7, SR: 2.3 ± 0.6 L/min; P < 0.01) and mitral regurgitation (LVP: 25.1 ± 10, BVP: 24.7 ± 11, baseline: 37.9 ± 14% jet area/left atria area; P < 0.01). LVP resulted in a smaller index of LV dyssynchrony than BVP (29 ± 10 vs 34 ± 14; P < 0.05). However, LVP exhibited a longer aortic preejection delay (220 ± 34 vs 186 ± 28 msec; P < 0.01), longer LV electromechanical delays (244.5 ± 39 vs 209.5 ± 47 msec; P < 0.05), greater interventricular dyssynchrony (56.6 ± 18 vs 31.4 ± 18; P < 0.01), and higher%DLC (40.1 ± 08 vs 30.3 ± 09; P < 0.05), leading to shorter LV filling time (387 ± 54 vs 348 ± 44 msec; P < 0.05) compared to BVP. Conclusion: Although LVP and BVP provide similar hemodynamic improvement, LVP results in more homogeneous but substantially delayed LV contraction, leading to shortened filling time and less reduction in postsystolic contraction. These data may influence the choice of individual optimal pacing configuration. [source]


Evaluation of Myocardial Performance with Conventional Single-Site Ventricular Pacing and Biventricular Pacing in a Canine Model of Atrioventricular Block

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2003
PATRICIO A. FRIAS M.D.
Introduction: The aim of this study was to evaluate epicardial biventricular pacing as a means of maintaining synchronous ventricular activation in an acute canine model of AV block with normal ventricular anatomy and function. Chronic single-site ventricular pacing results in dyssynchronous ventricular activation and may contribute to ventricular dysfunction. Biventricular pacing has been used successfully in adult patients with congestive heart failure. Methods and Results: This was an acute study of open chest mongrel dogs (n = 13). ECG, left ventricular (LV), aortic, and pulmonary arterial pressures were measured. LV impedance catheters were used to assess cardiodynamics using instantaneous LV pressure-volume relations (PVR). Following radiofrequency ablation of the AV node, a temporary pacemaker was programmed 10 beats/min above the intrinsic atrial rate, with an AV interval similar to the baseline intrinsic PR interval. The pacing protocol consisted of 5-minute intervals with the following lead configurations: right atrium-right ventricular apex (RA-RVA), RA-LV apex (LVA), and RA-biventricular using combinations of four ventricular sites (RVA, RV outflow tract [RVOT], LVA, LV base [LVB]). RA-RVA was used as the experimental control. LV systolic mechanics, as measured by the slope of the end-systolic (Ees) PVR (ESPVR, mmHg/cc), was statistically greater (P < 0.05) with all modes of biventricular pacing (RA-RVA/LVA 20.0 ± 2.9, RA-RVA/LVB 18.4 ± 2.9, RA-RVOT/LVA 15.1 ± 1.8, RA-RVOT/LVB 17.6 ± 2.9) compared to single-site ventricular pacing (RA-RVA 12.8 ± 1.6). Concurrent with this improvement in myocardial performance was a shortening of the QRS duration (RA-RVA 97.7 ± 2.9 vs RA-RVA/LVA 75.7 ± 4.9, RA-RVA/LVB 70.3 ± 4.9, RA-RVOT/LVA 65.3 ± 4.4, and RA-RVOT/LVB 76.7 ± 5.9, P < 0.05). Conclusion: In this acute canine model of AV block, QRS duration shortened and LV performance improved with epicardial biventricular pacing compared to standard single-site ventricular pacing. (J Cardiovasc Electrophysiol, Vol. 14, pp. 996-1000, September 2003) [source]


Long-Term Effects of Upgrading to Biventricular Pacing: Differences with Cardiac Resynchronization Therapy as Primary Indication

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 7 2010
GAETANO PAPARELLA M.D.
Background: Few studies have assessed the long-term effects of cardiac resynchronization therapy (CRT) in patients with advanced heart failure (HF) and previously right ventricular apical pacing (RVAP). Aims: To assess the clinical and hemodynamic impact of upgrading to biventricular pacing in patients with severe HF and permanent RVAP in comparison with patients who had CRT implantation as initial therapy. Methods and Results: Thirty-nine patients with RVAP, advanced HF (New York Heart Association [NYHA] III,IV), and severe depression of left ventricular ejection fraction (LVEF) were upgraded to biventricular pacing (group A). Mean duration of RVAP before upgrading was 41.8 ± 13.3 months. Clinical and echocardiographic results were compared to those obtained in a group of 43 patients with left bundle branch block and similar clinical characteristics undergoing "primary" CRT (group B). Mean follow-up was 35 ± 10 months in patients of group A and 38 ± 12 months in group B. NYHA class significantly improved in groups A and B. LVEF increased from 0.23 ± 0.07 to 0.36 ± 0.09 (P < 0.001) and from 0.26 ± 0.02 to 0.34 ± 0.10 (P < 0.001), respectively. Hospitalizations were reduced by 81% and 77% (P < 0.001). Similar improvements in echocardiographic signs of ventricular desynchronization were also observed. Conclusion: Patients upgraded to CRT exhibit long-term clinical and hemodynamic benefits that are similar to those observed in patients treated with CRT as initial strategy. (PACE 2010; 841,849) [source]


Collateral Approach for Biventricular Pacing of Coronary Sinus Ostium Obstruction

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2008
YOSHIMITSU SOGA M.D.
A 71-year-old man with dilated cardiomyopathy and complete atrioventricular block underwent cardiac resynchronization therapy (CRT) due to chronic heart failure that was not improved by conventional medical treatment. But we found the coronary vein ostium was completely obstructed by coronary venography. The contrast medium flowed out from the right atrium via a collateral pathway. Thus a left ventricular lead was placed via a collateral pathway and was successfully implanted without complications. The postoperative threshold was 2.7 V at 0.4 ms. The subjective symptom improved after CRT. The safety of this procedure was not clear. [source]


Feasibility Of Temporary Biventricular Pacing In Patients With Reduced Left Ventricular Function After Coronary Artery Bypass Grafting

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2007
FRANK EBERHARDT M.D.
Background and Methods: Biventricular pacing improves hemodynamics after weaning from cardiopulmonary bypass in patients with severely reduced left ventricular (LV) function undergoing coronary artery bypass grafting (CABG). We examined the feasibility of temporary biventricular pacing for 96 hours postoperatively. Unipolar epicardial wires were placed on the roof of the right atrium (RA), the right ventricular (RV) outflow tract, and the LV free lateral wall and connected to an external pacing device in 51 patients (mean LV ejection fraction 35 ± 4%). Pacing and sensing thresholds, lead survival and incidence of pacemaker dysfunction were determined. Results: Atrial and RV pacing thresholds increased significantly by the 4th postoperative day, from 1.6 ± 0.2 to 2.5 ± 0.3 V at 0.5 ms (P = 0.03) at the RA, 1.4 ± 0.3 V to 2.7 ± 0.4 mV (P = 0.01) at the RV, and 1.9 ± 0.6 V to 2.9 ± 0.7 mV (P = 0.3) at the LV, while sensing thresholds decreased from 2.0 ± 0.2 to 1.7 ± 0.2 mV (P = 0.18) at the RA, 7.2 ± 0.8 to 5.1 ± 0.7 mV (P = 0.05) at the RV, and 9.4 ± 1.3 to 5.5 ± 1.1 mV (P = 0.02) at the LV. The cumulative overall incidence of lead failure was 24% by the 4th postoperative day, and was similar at the RV and LV. We observed no ventricular proarrhythmia due to pacing or temporary pacemaker malfunction. Conclusions: Biventricular pacing after CABG using a standard external pacing system was feasible and safe. [source]


Upgrading Pacing Generators in the Era of Biventricular Pacing

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 7 2006
GERRY C. KAYE
No abstract is available for this article. [source]


Biventricular Pacing for Severe Mitral Reguritation Following Atrioventrgicular Nodal Ablation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2p1 2003
PATRICK J.S. DISNEY
DISNEY, P.J.S., et al.: Biventricular Pacing for Severe Mitral Regurgitation Following Atrioventricular Nodal Ablation. A 69-year-old woman developed acute pulmonary edema and severe mitral regurgitation (MR) 2 days following an uncomplicated AV nodal (AVN) ablation and insertion of VVI pacemaker for chronic atrial fibrillation. There was no history of significant mitral valve disease. Left ventricular function was normal and there was no evidence of an acute cardiac ischemic event. Transthoracic echo and right heart catheterization studies showed reduction in the severity of MR with biventricular pacing as opposed to RV pacing alone. A permanent pacemaker configured for biventricular pacing was implanted with complete resolution of symptoms and significant reduction in degree of MR. (PACE 2003; 26[Pt. I]:643,644) [source]


Which Patients with Congestive Heart Failure May Benefit from Biventricular Pacing?

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p2 2003
NESTOR O. GALIZIO
GALIZIO, N.O., et al.: Which Patients with Congestive Heart Failure May Benefit from Biventricular Pacing?Background: Biventricular pacing improves the clinical status and ventricular function in patients with congestive heart failure (CHF) and intraventricular conduction delay. However, patient selection criteria including NYHA functional class, rhythm, PR interval, QRS duration (QRSd), left ventricular ejection fraction (LVEF), left ventricular diastolic diameter (LVDD), and other variables are not clearly defined. Objective: To determine which and how many patients referred for an initial cardiac transplantation evaluation may be eligible for biventricular pacing (BP) according to the criteria of recently completed trials of cardiac resynchronization therapy (CRT). Methods: This was a retrospective review of 200 patients, whose mean age was51 ± 13years (173 men). Sinus rhythm was present in 88% of the patients, 107 had a QRSd >120 ms, and 38% had left bundle branch block. LVDD was72.5 ± 12 mmand LVEF21.7 ± 9.3%; 54% had mitral regurgitation. Results: When NYHA class, electrocardiographic, and ventricular function criteria were considered separately, a high proportion of patients appeared to be candidates for CRT: 70.5% were in NYHA functional class III/IV, 34% had QRSd ,150 ms, 60% had LVDD ,60 mm and 53.5% LVEF ,35%. However, the proportions of patients eligible for CRT were different according to the selection criteria of recently completed trials: 18% of the patients with InSync criteria, 13% of the patients with MUSTIC SR criteria, 0.5% with MUSTIC AF criteria, 27% of patients with MIRACLE criteria, and 35% of the patients with CONTAK CD criteria (without considering indications for implantable cardioverter defibrillator). Conclusion: In this population-based study, a wide range of patients (13% to 35%) would have been candidates for CRT, according to the selection criteria of different completed trials.(PACE 2003; 26[Pt. II]:158,161) [source]


Biventricular Pacing Using Two Pacemakers and the Triggered VVT Mode

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2001
BRENDAN O'COCHLAIN
O'COCHLAIN, B., et al.: Biventricular Pacing Using Two Pacemakers and the Triggered VVT Mode. Pacemaker dependent patients exhibit interventricular conduction delay due to right ventricular lead placement. The addition of a transvenous coronary sinus lead for biventricular pacing has been shown to be effective. Venous stenosis and thrombosis postpacemaker implantation can occur in up to 35% of patients. This report describes a patient with a preexisting left-sided dual chamber pacemaker and chronic left subclavian vein occlusion that was upgraded to a biventricular system by placing a coronary sinus lead and single chamber ventricular triggered pacemaker on the opposite side. [source]


Biventricular Pacing as Alternative Therapy for Dilated Cardiomyopathy Associated with Congenital Heart Disease

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2001
EDWIN RODRÍGUEZ-CRUZ
RODRÍGUEZ-CRUZ, E., et al.: Biventricular Pacing as Alternative Therapy for Dilated Cardiomyopathy Associated with Congenital Heart Disease. Biventricular, alternative, and multisite pacing are currently being explored to improve cardiac function among patients with medically refractory, end-stage dilated cardiomyopathies. Although, due to inherent myocardial abnormalities, patients with repaired congenital heart defects may be at a greater risk than others to develop heart failure, often requiring cardiac transplantation. The efficacy of biventricular pacing among these patients is unknown. This report presents a patient with successfully repaired congenital heart disease in infancy who developed a symptomatic dilated cardiomyopathy at 22 years of age. Following biventricular pacing, systemic ventricular function showed a 14% improvement in ventricular dP/dt. One month later, subjective symptoms improved and cardiac ultrasound illustrated a 125% increase in fractional area of change. Exercise stress testing showed a 17% improvement in aerobic work capacity. [source]


Optimization of Repolarization during Biventricular Pacing: A New Target in Patients with Biventricular Devices?

ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2010
Cengizhan Türko, lu M.D.
Background: Evaluation of repolarization during sequentional biventricular pacing. Methods: Patients with biventricular devices, and left ventricular leads placed to the basal part of lateral left ventricular wall were enrolled. QRS, QTc, JTc, and corrected Tpeak-Tend intervals were compared during sequentional biventricular, left ventricular, and right ventricular pacing. Results: Five patients with nonischemic and five with ischemic cardiomyopathy due to anterior myocardial infarction were enrolled. No correlation was observed between values of repolarization among patients. The optimal values of repolarization were significantly different from values of echocardiographically guided hemodynamic optimization. Two patients with biventricular pacing-induced ventricular fibrillation were successfully treated by reprogramming of V-V delay according to interventricular delay resulting in shorter Tpeak-Tend interval, although delayed effect of amiodarone in one of these patients cannot be ruled out. Conclusions: Patients with biventricular devices may be prone to development of ventricular arrhythmias depending on programmed V-V interval. We suggest that optimization of repolarization may be performed in patients with biventricular pacemakers in the absence of backup ICD and those with frequent episodes of ventricular tachyarrhythmias, although this finding deserves further study. Ann Noninvasive Electrocardiol 2010;15(1):36,42 [source]


Evaluation of Myocardial Performance with Conventional Single-Site Ventricular Pacing and Biventricular Pacing in a Canine Model of Atrioventricular Block

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2003
PATRICIO A. FRIAS M.D.
Introduction: The aim of this study was to evaluate epicardial biventricular pacing as a means of maintaining synchronous ventricular activation in an acute canine model of AV block with normal ventricular anatomy and function. Chronic single-site ventricular pacing results in dyssynchronous ventricular activation and may contribute to ventricular dysfunction. Biventricular pacing has been used successfully in adult patients with congestive heart failure. Methods and Results: This was an acute study of open chest mongrel dogs (n = 13). ECG, left ventricular (LV), aortic, and pulmonary arterial pressures were measured. LV impedance catheters were used to assess cardiodynamics using instantaneous LV pressure-volume relations (PVR). Following radiofrequency ablation of the AV node, a temporary pacemaker was programmed 10 beats/min above the intrinsic atrial rate, with an AV interval similar to the baseline intrinsic PR interval. The pacing protocol consisted of 5-minute intervals with the following lead configurations: right atrium-right ventricular apex (RA-RVA), RA-LV apex (LVA), and RA-biventricular using combinations of four ventricular sites (RVA, RV outflow tract [RVOT], LVA, LV base [LVB]). RA-RVA was used as the experimental control. LV systolic mechanics, as measured by the slope of the end-systolic (Ees) PVR (ESPVR, mmHg/cc), was statistically greater (P < 0.05) with all modes of biventricular pacing (RA-RVA/LVA 20.0 ± 2.9, RA-RVA/LVB 18.4 ± 2.9, RA-RVOT/LVA 15.1 ± 1.8, RA-RVOT/LVB 17.6 ± 2.9) compared to single-site ventricular pacing (RA-RVA 12.8 ± 1.6). Concurrent with this improvement in myocardial performance was a shortening of the QRS duration (RA-RVA 97.7 ± 2.9 vs RA-RVA/LVA 75.7 ± 4.9, RA-RVA/LVB 70.3 ± 4.9, RA-RVOT/LVA 65.3 ± 4.4, and RA-RVOT/LVB 76.7 ± 5.9, P < 0.05). Conclusion: In this acute canine model of AV block, QRS duration shortened and LV performance improved with epicardial biventricular pacing compared to standard single-site ventricular pacing. (J Cardiovasc Electrophysiol, Vol. 14, pp. 996-1000, September 2003) [source]


Electrocardiogram-Based Algorithm to Predict the Left Ventricular Lead Position in Recipients of Cardiac Resynchronization Systems

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2009
SYLVAIN PLOUX M.D.
Introduction: Biventricular pacing is associated with various electrocardiographic patterns depending on the position of the left ventricular (LV) lead. We aimed to develop an electrocardiogram-based algorithm to predict the position of the LV lead. Methods: The algorithm was developed in 100 consecutive recipients of cardiac resynchronization therapy (CRT) systems. QRS axis, morphology, and polarity were analyzed with a view to define the specific electrocardiographic characteristics associated with the various LV lead positions. The algorithm was prospectively validated in 50 consecutive CRT device recipients. Results: The first analysis of the algorithm was the QRS morphology in V1. A positive R wave in V1 suggested LV lateral or posterior wall stimulation. A QS pattern was specific of anterior LV leads. In the presence of an R wave in V1, V6 was analyzed to distinguish between an inferior and anterior LV lead. Inferior leads were never associated with a positive V6. To differentiate between lateral and posterior positions, we analyzed the pattern in V2. Lateral leads were associated with an R morphology in V1 and a negative V2. Posterior leads were associated with an R morphology in V1 and V2. The algorithm allowed a reliable distinction between an inferior or anterior and a lateral or posterior lead position in 90% of patients. Inferior, anterior, lateral, and posterior positions were reliably distinguished in 80% of patients. Conclusion: This algorithm predicted the position of the LV lead with a high sensitivity and predictive value. [source]


Feasibility Of Temporary Biventricular Pacing In Patients With Reduced Left Ventricular Function After Coronary Artery Bypass Grafting

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2007
FRANK EBERHARDT M.D.
Background and Methods: Biventricular pacing improves hemodynamics after weaning from cardiopulmonary bypass in patients with severely reduced left ventricular (LV) function undergoing coronary artery bypass grafting (CABG). We examined the feasibility of temporary biventricular pacing for 96 hours postoperatively. Unipolar epicardial wires were placed on the roof of the right atrium (RA), the right ventricular (RV) outflow tract, and the LV free lateral wall and connected to an external pacing device in 51 patients (mean LV ejection fraction 35 ± 4%). Pacing and sensing thresholds, lead survival and incidence of pacemaker dysfunction were determined. Results: Atrial and RV pacing thresholds increased significantly by the 4th postoperative day, from 1.6 ± 0.2 to 2.5 ± 0.3 V at 0.5 ms (P = 0.03) at the RA, 1.4 ± 0.3 V to 2.7 ± 0.4 mV (P = 0.01) at the RV, and 1.9 ± 0.6 V to 2.9 ± 0.7 mV (P = 0.3) at the LV, while sensing thresholds decreased from 2.0 ± 0.2 to 1.7 ± 0.2 mV (P = 0.18) at the RA, 7.2 ± 0.8 to 5.1 ± 0.7 mV (P = 0.05) at the RV, and 9.4 ± 1.3 to 5.5 ± 1.1 mV (P = 0.02) at the LV. The cumulative overall incidence of lead failure was 24% by the 4th postoperative day, and was similar at the RV and LV. We observed no ventricular proarrhythmia due to pacing or temporary pacemaker malfunction. Conclusions: Biventricular pacing after CABG using a standard external pacing system was feasible and safe. [source]


Which Patients with Congestive Heart Failure May Benefit from Biventricular Pacing?

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p2 2003
NESTOR O. GALIZIO
GALIZIO, N.O., et al.: Which Patients with Congestive Heart Failure May Benefit from Biventricular Pacing?Background: Biventricular pacing improves the clinical status and ventricular function in patients with congestive heart failure (CHF) and intraventricular conduction delay. However, patient selection criteria including NYHA functional class, rhythm, PR interval, QRS duration (QRSd), left ventricular ejection fraction (LVEF), left ventricular diastolic diameter (LVDD), and other variables are not clearly defined. Objective: To determine which and how many patients referred for an initial cardiac transplantation evaluation may be eligible for biventricular pacing (BP) according to the criteria of recently completed trials of cardiac resynchronization therapy (CRT). Methods: This was a retrospective review of 200 patients, whose mean age was51 ± 13years (173 men). Sinus rhythm was present in 88% of the patients, 107 had a QRSd >120 ms, and 38% had left bundle branch block. LVDD was72.5 ± 12 mmand LVEF21.7 ± 9.3%; 54% had mitral regurgitation. Results: When NYHA class, electrocardiographic, and ventricular function criteria were considered separately, a high proportion of patients appeared to be candidates for CRT: 70.5% were in NYHA functional class III/IV, 34% had QRSd ,150 ms, 60% had LVDD ,60 mm and 53.5% LVEF ,35%. However, the proportions of patients eligible for CRT were different according to the selection criteria of recently completed trials: 18% of the patients with InSync criteria, 13% of the patients with MUSTIC SR criteria, 0.5% with MUSTIC AF criteria, 27% of patients with MIRACLE criteria, and 35% of the patients with CONTAK CD criteria (without considering indications for implantable cardioverter defibrillator). Conclusion: In this population-based study, a wide range of patients (13% to 35%) would have been candidates for CRT, according to the selection criteria of different completed trials.(PACE 2003; 26[Pt. II]:158,161) [source]


Echocardiographic Features of Patients With Heart Failure Who May Benefit From Biventricular Pacing

ECHOCARDIOGRAPHY, Issue 3 2003
Amgad N. Makaryus
Background: Recent studies suggest that cardiac resynchronization therapy through biventricular pacing (BVP) may be a promising new treatment for patients with advanced congestive heart failure (CHF). This method involves implantation of pacer leads into the right atrium (RA), right ventricle (RV), and coronary sinus (CS) in patients with ventricular dyssynchrony as evidenced by a bundle branch block pattern on electrocardiogram (ECG). Clinical trials are enrolling stable patients with ejection fractions (EF) , 35%, left ventricular end-diastolic diameters (LVIDd) , 54 mm, and QRS duration ,140 msec. We compared echocardiography features of these patients (group 1) with other patients with EF , 35%, LVIDd , 54 mm, and QRS < 140 msec (group 2 = presumably no dyssynchrony). Methods: Nine hundred fifty-one patients with CHF, LVID 54 mm, EF 35% by echocardiography were retrospectively evaluated. One hundred forty-five patients remained after those with primary valvular disease, prior pacing systems, or chronic atrial arrhythmias were excluded. From this group of 145 patients, a subset of 50 randomly selected patients were further studied (25 patients [7 females, 18 males] from group 1, and 25 patients [7 females, 18 males] from group 2). Mean age group 1 = 75 years old, mean age group 2 = 67 years old. Mean QRS group 1 = 161 msec, mean QRS group 2 = 110 msec. Each group was compared for presence of paradoxical septal motion, atrial and ventricular chamber sizes, LV mass, LVEF, and RV systolic function. Results: Of the initial group of 951 patients, 145 (15%) met inclusion criteria. In the substudy, 20/25 (80%) of group l and 7/25 (28%) of group 2 subjects had paradoxical septal motion on echo (Fisher's exact test, P = 0.0005). The t-tests performed on the other echocardiography variables demonstrated no differences in chamber size, function, or LV mass. Conclusions: Cardiac resynchronization therapy with BVP appears to target a relatively small population of our advanced CHF patients (15% or less). Although increasing QRS duration on ECG is associated with more frequent paradoxical septal motion on echo, it is not entirely predictive. Paradoxical septal motion on echo may therefore be more sensitive at identifying patients who respond to BVP. Further prospective studies are needed. (ECHOCARDIOGRAPHY, Volume 20, April 2003) [source]


Validation of a New Noninvasive Device for the Monitoring of Peak Endocardial Acceleration in Pigs: Implications for Optimization of Pacing Site and Configuration

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2008
PIERRE BORDACHAR M.D.
Introduction: The peak of endocardial acceleration (PEA) is an index of myocardial contractility. We aimed to (1) demonstrate that the PEA measured by the noninvasive cutaneous precordial application of an accelerometer sensor is related to left ventricular (LV) dP/dt max and (2) assess the usefulness of PEA monitoring during graded ischemia and during different configurations of sequential biventricular pacing. Methods and Results: Measurements of invasive LV dP/dt max were compared with measurements of transcutaneous PEA in seven pigs at baseline and during acute drug infusions; increased heart rate; right, left, biventricular and sequential biventricular pacing before and after graded ischemia induced by the constriction of the left anterior descending coronary artery. A consistent PEA signal was obtained in all animals. PEA changes were highly related to LV dP/dt max changes (r= 0.93; P < 0.001). The changes of LV contractility induced by the different pacing configurations were detected by PEA analysis in the absence of ischemia (r= 0.94; P < 0.001) and in the presence of ischemic LV dysfunction (r= 0.91; P < 0.001). Conclusion: Noninvasive PEA measurement allows monitoring of left ventricular contractility and may be a useful tool to detect global effect of ventricular ischemia and to optimize the choice of both pacing site and pacing configuration. [source]


Successful Catheter Ablation of Two Types of Ventricular Tachycardias Triggered by Cardiac Resynchronization Therapy: A Case Report

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2007
PETR PEICHL M.D., Ph.D.
We report a case of a patient with nonischemic dilated cardiomyopathy and implantable cardioverter-defibrillator, in whom an upgrade to biventricular pacing triggered multiple episodes of ventricular tachycardias (VTs) of two morphologies. First VT presented as repetitive nonsustained arrhythmia of the same morphology as isolated ectopic beats, suggesting its focal origin. Second VT was reentrant and was triggered by the former ectopy, leading to a therapy from the device. Electroanatomical mapping of the left ventricle revealed relatively small low voltage area in the left ventricular outflow tract and identified both an arrhythmogenic focus as well as critical isthmus for reentrant VT. Radiofrequency catheter ablation successfully abolished both VTs. After the procedure, biventricular pacing was continued without any recurrences during a period of 24 months. The report emphasizes the role of catheter ablation in management of VTs triggered by cardiac resynchronization therapy. [source]


Biventricular Pacing and Left Ventricular Pacing in Heart Failure:

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2004
Similar Hemodynamic Improvement Despite Marked Electromechanical Differences
Introduction: We conducted an acute echocardiographic study comparing hemodynamic and ventricular dyssynchrony parameters during left ventricular pacing (LVP) and biventricular pacing (BVP). We sought to clarify the mechanisms responsible for similar hemodynamic improvement despite differences in electrical activation. Methods and Results: Thirty-three patients underwent echocardiography prior to implantation with a multisite pacing device (spontaneous rhythm [SR]) and 2 days after implantation (BVP and LVP). Interventricular dyssynchrony (pulsed-wave Doppler), extent of myocardium displaying delayed longitudinal contraction (%DLC; tissue tracking), and index of LV dyssynchrony (pulsed-wave tissue Doppler imaging) were assessed. Compared to SR, BVP and LVP caused similar significant improvement of cardiac output (LVP: 3.2 ± 0.5, BVP: 3.1 ± 0.7, SR: 2.3 ± 0.6 L/min; P < 0.01) and mitral regurgitation (LVP: 25.1 ± 10, BVP: 24.7 ± 11, baseline: 37.9 ± 14% jet area/left atria area; P < 0.01). LVP resulted in a smaller index of LV dyssynchrony than BVP (29 ± 10 vs 34 ± 14; P < 0.05). However, LVP exhibited a longer aortic preejection delay (220 ± 34 vs 186 ± 28 msec; P < 0.01), longer LV electromechanical delays (244.5 ± 39 vs 209.5 ± 47 msec; P < 0.05), greater interventricular dyssynchrony (56.6 ± 18 vs 31.4 ± 18; P < 0.01), and higher%DLC (40.1 ± 08 vs 30.3 ± 09; P < 0.05), leading to shorter LV filling time (387 ± 54 vs 348 ± 44 msec; P < 0.05) compared to BVP. Conclusion: Although LVP and BVP provide similar hemodynamic improvement, LVP results in more homogeneous but substantially delayed LV contraction, leading to shortened filling time and less reduction in postsystolic contraction. These data may influence the choice of individual optimal pacing configuration. [source]


Orthodromic Pacemaker-Mediated Tachycardia in a Biventricular System Without an Atrial Electrode

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2004
ANTONIO BERRUEZO M.D.
Pacemaker-mediated tachycardia is a well-known complication of dual-chamber devices. In this report, we describe for the first time a case of orthodromic pacemaker-mediated tachycardia in a patient in whom a biventricular system without an atrial electrode had been implanted. Retrograde atrial activation was directly produced by the dislodged coronary vein electrode in the AV groove, resulting in simultaneous capture of the left atrium and left ventricle. During tachycardia, AV nodal conduction was via the anterograde pathway of the circuit and limited the ventricular response. Subsequently, right ventricular activation was sensed by the right ventricular electrode that triggered biventricular pacing and left atrial capture, perpetuating the tachycardia. Because the left atrial threshold was higher than the left ventricular threshold, the problem could be resolved easily by lowering the output of the coronary vein electrode. [source]


Increase in Ventricular Tachycardia Frequency After Biventricular Implantable Cardioverter Defibrillator Upgrade

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2003
JOSE M. GUERRA M.D.
We report the case of a patient in whom transvenous left ventricular pacing lead placement at the time of a biventricular upgrade led to an exacerbation of clinical monomorphic ventricular tachycardia (MVT). At implant, slow left ventricular pacing repeatedly induced sustained MVT. However, testing of the biventricular pacing showed no MVT inducibility, and the system was implanted. The patient was readmitted due to multiple episodes of the MVT observed at implant. The MVT was controlled with pharmacotherapy, allowing the patient to continue with biventricular pacing. (J Cardiovasc Electrophysiol, Vol. 14, pp. 1245-1247, November 2003) [source]


Evaluation of Myocardial Performance with Conventional Single-Site Ventricular Pacing and Biventricular Pacing in a Canine Model of Atrioventricular Block

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2003
PATRICIO A. FRIAS M.D.
Introduction: The aim of this study was to evaluate epicardial biventricular pacing as a means of maintaining synchronous ventricular activation in an acute canine model of AV block with normal ventricular anatomy and function. Chronic single-site ventricular pacing results in dyssynchronous ventricular activation and may contribute to ventricular dysfunction. Biventricular pacing has been used successfully in adult patients with congestive heart failure. Methods and Results: This was an acute study of open chest mongrel dogs (n = 13). ECG, left ventricular (LV), aortic, and pulmonary arterial pressures were measured. LV impedance catheters were used to assess cardiodynamics using instantaneous LV pressure-volume relations (PVR). Following radiofrequency ablation of the AV node, a temporary pacemaker was programmed 10 beats/min above the intrinsic atrial rate, with an AV interval similar to the baseline intrinsic PR interval. The pacing protocol consisted of 5-minute intervals with the following lead configurations: right atrium-right ventricular apex (RA-RVA), RA-LV apex (LVA), and RA-biventricular using combinations of four ventricular sites (RVA, RV outflow tract [RVOT], LVA, LV base [LVB]). RA-RVA was used as the experimental control. LV systolic mechanics, as measured by the slope of the end-systolic (Ees) PVR (ESPVR, mmHg/cc), was statistically greater (P < 0.05) with all modes of biventricular pacing (RA-RVA/LVA 20.0 ± 2.9, RA-RVA/LVB 18.4 ± 2.9, RA-RVOT/LVA 15.1 ± 1.8, RA-RVOT/LVB 17.6 ± 2.9) compared to single-site ventricular pacing (RA-RVA 12.8 ± 1.6). Concurrent with this improvement in myocardial performance was a shortening of the QRS duration (RA-RVA 97.7 ± 2.9 vs RA-RVA/LVA 75.7 ± 4.9, RA-RVA/LVB 70.3 ± 4.9, RA-RVOT/LVA 65.3 ± 4.4, and RA-RVOT/LVB 76.7 ± 5.9, P < 0.05). Conclusion: In this acute canine model of AV block, QRS duration shortened and LV performance improved with epicardial biventricular pacing compared to standard single-site ventricular pacing. (J Cardiovasc Electrophysiol, Vol. 14, pp. 996-1000, September 2003) [source]


Noninvasive Assessment of Cardiac Resynchronization Therapy for Congestive Heart Failure Using Myocardial Strain and Left Ventricular Peak Power as Parameters of Myocardial Synchrony and Function

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2002
Ph.D., ZORAN B. POPOVI
Resynchronization Therapy for Heart Failure.Introduction: Although invasive studies have shown that cardiac resynchronization therapy by biventricular pacing improves left ventricular (LV) function in selected heart failure patients, it is impractical to apply such techniques in the clinical setting. The aim of this study was to assess the acute effects of cardiac resynchronization therapy by noninvasive techniques. Methods and Results: Twenty-two patients enrolled in the InSync trial (age 64 ± 9 years, 18 men and 4 women; all with ejection fraction <35% and QRS >130 msec) were studied 1 to 12 months after pacemaker implantation during pacing, and while ventricular pacing was inhibited. Regional myocardial strains of the interventricular septum, LV free wall, and right ventricular free wall were derived from color Doppler tissue echocardiography. Peak power index was calculated as a product of simultaneously recorded noninvasive blood pressure and pulse-wave (PW) Doppler velocity of the LV outflow tract. The Z ratio (sum of LV ejection and filling times divided by RR interval) and tei index were calculated from PW Doppler data. During pacing, overall regional strain improved (P = 0.01), while the LV strain coefficient of variation decreased from 2.7 ± 2.4 to 1.3 ± 0.7 (P = 0.009). Additionally, peak power index improved from 84 ± 24 to 94 ± 27 cm· mmHg/sec (P = 0.004). The Z ratio increased from 0.71 ± 0.08 to 0.78 ± 0.07 (P = 0.0005), while the tei index decreased from 0.86 ± 0.33 to 0.59 ± 0.16 (P = 0.0002). Conclusion: Using novel noninvasive indices, we demonstrated that cardiac resynchronization therapy improves LV performance. [source]


Long-Term Effects of Upgrading to Biventricular Pacing: Differences with Cardiac Resynchronization Therapy as Primary Indication

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 7 2010
GAETANO PAPARELLA M.D.
Background: Few studies have assessed the long-term effects of cardiac resynchronization therapy (CRT) in patients with advanced heart failure (HF) and previously right ventricular apical pacing (RVAP). Aims: To assess the clinical and hemodynamic impact of upgrading to biventricular pacing in patients with severe HF and permanent RVAP in comparison with patients who had CRT implantation as initial therapy. Methods and Results: Thirty-nine patients with RVAP, advanced HF (New York Heart Association [NYHA] III,IV), and severe depression of left ventricular ejection fraction (LVEF) were upgraded to biventricular pacing (group A). Mean duration of RVAP before upgrading was 41.8 ± 13.3 months. Clinical and echocardiographic results were compared to those obtained in a group of 43 patients with left bundle branch block and similar clinical characteristics undergoing "primary" CRT (group B). Mean follow-up was 35 ± 10 months in patients of group A and 38 ± 12 months in group B. NYHA class significantly improved in groups A and B. LVEF increased from 0.23 ± 0.07 to 0.36 ± 0.09 (P < 0.001) and from 0.26 ± 0.02 to 0.34 ± 0.10 (P < 0.001), respectively. Hospitalizations were reduced by 81% and 77% (P < 0.001). Similar improvements in echocardiographic signs of ventricular desynchronization were also observed. Conclusion: Patients upgraded to CRT exhibit long-term clinical and hemodynamic benefits that are similar to those observed in patients treated with CRT as initial strategy. (PACE 2010; 841,849) [source]


Use of Radiofrequency Perforation for Lead Placement in Biventricular or Conventional Endocardial Pacing after Mustard or Senning Operations for D-Transposition of the Great Arteries

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2009
SANTABHANU CHAKRABARTI M.D.
Background: Endocardial pacemaker lead placement can be challenging after Mustard and Senning operations for transposition of the great arteries (D-TGA), if there is atresia of the systemic venous pathways and because the coronary sinus cannot be used for cardiac resynchronization therapy. Radiofrequency (RF)-assisted perforation techniques have been used in congenital heart disease but have not been reported for use in pacemaker implantation. Methods and Results: We describe RF perforation of an atretic superior systemic venous pathway and systemic venous baffles in three patients after Senning and Mustard operations to implant endocardial pacing systems to achieve conventional or biventricular pacing. Conclusions: RF-energy-assisted perforation is feasible and effective tool to facilitate endocardial lead placement during dual-chamber and biventricular pacemaker implantation in patients with Mustard or Senning operations for D-TGA. [source]


Evidence for Electrical Remodeling of the Native Conduction System with Cardiac Resynchronization Therapy

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2007
CHARLES A. HENRIKSON M.D.
Background:Cardiac resynchronization therapy (CRT) improves hemodynamics and decreases heart failure symptoms. However, the potential of CRT to bring about electrical remodeling of the heart has not been investigated. Methods and Results:We studied 25 patients, of whom 17 had a nonischemic cardiomyopathy, and 8 had an ischemic cardiomyopathy; 16 had left bundle branch block (LBBB), 1 right bundle branch block (RBBB), and 8 nonspecific intraventricular conduction delay. During routine device clinic visits, patients with chronic biventricular pacing (>6 months) were reprogrammed to VVI 40 to allow for native conduction to resume. After 5 minutes of native rhythm, a surface electrocardiogram (ECG) was recorded, and then the previous device settings were restored. This ECG was compared to the preimplant ECG. Preimplant mean ejection fraction was 19% (range, 10%,35%), and follow-up mean ejection fraction was 35% (12.5%,65%). Mean time from implant to follow-up ECG was 14 months (range, 6,31). The QRS interval prior to CRT was 155 ± 29 ms, and shortened to 144 ± 31 ms (P = 0.0006), and the QRS axis shifted from ,1 ± 59 to ,26 ± 53 (P = 0.03). There was no significant change in PR or QTc interval, or in heart rate. Conclusion:CRT leads to a decrease in the surface QRS duration, without affecting other surface ECG parameters. The reduced electrical activation time may reflect changes in the specialized conduction system or in intramyocardial impulse transmission. [source]


Simple Access to the Coronary Venous System for Left Ventricular Pacing

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2003
DANY E. SAYAD
Implantation of the LV lead for biventricular pacing can be challenging, time consuming, and often requires extensive fluoroscopy time. A conventional diagnostic 5 Fr left Amplatz catheter was used to cannulate the coronary sinus in 15 consecutive patients undergoing implantation of a biventricular pacemaker. When the coronary sinus was cannulated, the proximal end of the Amplatz catheter was cut and the coronary sinus sheath was passed over the Amplatz catheter that was then removed. Coronary sinus cannulation was achieved in all 15 patients with a mean fluoroscopy time of3.34 ± 1.9 minutes. Subsequent implantation of a biventricular pacemaker was successful and free of complications in all the 15 patients. (PACE 2003; 26:1856,1858) [source]


Biventricular Pacing for Severe Mitral Reguritation Following Atrioventrgicular Nodal Ablation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2p1 2003
PATRICK J.S. DISNEY
DISNEY, P.J.S., et al.: Biventricular Pacing for Severe Mitral Regurgitation Following Atrioventricular Nodal Ablation. A 69-year-old woman developed acute pulmonary edema and severe mitral regurgitation (MR) 2 days following an uncomplicated AV nodal (AVN) ablation and insertion of VVI pacemaker for chronic atrial fibrillation. There was no history of significant mitral valve disease. Left ventricular function was normal and there was no evidence of an acute cardiac ischemic event. Transthoracic echo and right heart catheterization studies showed reduction in the severity of MR with biventricular pacing as opposed to RV pacing alone. A permanent pacemaker configured for biventricular pacing was implanted with complete resolution of symptoms and significant reduction in degree of MR. (PACE 2003; 26[Pt. I]:643,644) [source]