Acute Effects of Intraoperative Multisite Ventricular Pacing on Left Ventricular Function and Activation/Contraction Sequence in Patients with Depressed Ventricular Function

Department of Medicine, University of California, San Francisco, San Francisco, California, United States
Journal of Cardiovascular Electrophysiology (Impact Factor: 2.96). 01/1998; 9(1):13-21. DOI: 10.1111/j.1540-8167.1998.tb00862.x
Source: PubMed


We hypothesized that simultaneous right and left ventricular apical pacing would result in improvement in left ventricular function due to improved coordination of segmental ventricular contraction. Structural changes in ventricular muscle present in dilated cardiomyopathy compromise ventricular excitation and mechanical contraction. METHODS and
Eleven patients with depressed left ventricular function having cardiac surgery underwent epicardial multisite pacing with continuous transesophageal echocardiographic imaging. Quantitative measurement of percent fractional area change was performed, and segmental changes in contraction sequence resulting from simultaneous right and left ventricular pacing were assessed by application of phase analysis to recorded transesophageal images. There was no statistically significant difference between the paced QRS duration achieved with simultaneous right and left ventricular apical pacing and the native QRS duration (139+/-39 msec vs 106+/-18 msec, P = NS), but all other paced modes resulted in longer QRS durations. Percent fractional area change improved with simultaneous right and left ventricular apical pacing but not with other paced modes (41.5+/-11.9 vs 34.3+/-9.7, P < 0.01). Phase analysis demonstrated a resequencing of segmental left ventricular activation/contraction when compared to baseline ventricular activation.
Simultaneous right and left ventricular apical pacing results in acute improvements in global ventricular performance in patients with depressed ventricular function. Improvements may result from pacing-induced global coordination through recruitment of left and right ventricular apical and septal segments critical to effective ventricular contraction.

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    • "Recent studies revealed a reverse remodeling in left ventricle with cardiac resynchronization therapy (Saxon et al. 1998; Lau et al. 2000; Stellbrink et al. 2001; Sogaard et al. 2002; Pitzalis et al. 2002). However, changes in left atrial remodeling and effects on SEC have not been adequately evaluated. "
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    The Tohoku Journal of Experimental Medicine 03/2004; 202(2):143-53. DOI:10.1620/tjem.202.143 · 1.35 Impact Factor
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    • "The selection criteria used in this review were prespecified and were based on the applicability of right ventricular outflow-tract pacing to a wide range of patients selected for pacemaker implantation for symptomatic bradyarrhythmias. Therefore, studies that used epicardial stimula- tion [8] [9] [17] [21] [23] and studies in selected patients [10] [12] [13] were not included in the final analysis. There are several important limitations of this retrospective meta-analysis that need to be emphasized. "
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    ABSTRACT: The right ventricular apex has been used for cardiac stimulation because this position is easily accessible and is associated with a stable position of the electrode with a low dislodgement rate. This position, however, is associated with a dyssynchronous left ventricular contraction with subsequent deleterious haemodynamic effects. Alternative stimulation sites have been studied extensively because of a potentially better haemodynamic effect compared with right ventricular apex pacing. Using a Cochrane search strategy, nine studies were selected to analyze the haemodynamic effects of right ventricular outflow-tract pacing. The results of these studies (n=217) were pooled and indicated a significantly better haemodynamic effect (odds ratio 0.34, confidence interval 0.15-0.53) compared with right ventricular apex pacing. Therefore, these data suggest that right ventricular outflow-tract pacing may offer a modest but significant benefit over right ventricular apex pacing in patients selected for pacemaker implantation on the basis of symptomatic bradyarrhythmias.
    Europace 08/2003; 5(3):275-8. · 3.67 Impact Factor
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    • "Ventricular dysynchrony , due to interventricular and intraventricular conduction delays, is associated with paradoxical septal wall motion, pre-systolic mitral regurgitation, reduced diastolic filling times and delayed activation of free wall segments which may contract after aortic valve closure [6] [7] [8] [9] . Acute studies demonstrated that biventricular pacing, and maybe left ventricular pacing alone, may improve both systolic and diastolic function [10] [11] [12] [13] [14] [15] [16] [17] . "
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