Right Ventricular Outflow Tract Septal Pacing Is Superior to Right Ventricular Apical Pacing

Abstract

BackgroundThe effects of right ventricular apical pacing (RVAP) and right ventricular outflow tract (RVOT) septal pacing on atrial and ventricular electrophysiology have not been thoroughly compared.Methods and ResultsTo identify a more favorable pacing strategy with fewer adverse effects, 80 patients who had complete atrioventricular block with normal cardiac function and who were treated with either RVAP (n=42) or RVOT septal pacing (n=38) were recruited after an average of 2 years of follow‐up. The data from electrocardiography and echocardiography performed before pacemaker implantation and at the end of follow‐up were collected. The patients in the RVOT septal pacing and RVAP groups showed similar demographic and clinical characteristics before pacing treatments. After a mean follow‐up of 2 years, the final maximum P‐wave duration; P‐wave dispersion; Q‐, R‐, and S‐wave complex duration; left atrial volume index; left ventricular end‐systolic diameter; ratio of transmitral early diastolic filling velocity to mitral annular early diastolic velocity; and interventricular mechanical delay in the RVOT septal pacing group were significantly less than those in the RVAP group (P<0.05). The final left ventricular ejection fraction of the RVOT septal pacing group was significantly higher than that of the RVAP group (P<0.05).ConclusionsCompared with RVAP, RVOT septal pacing has fewer adverse effects regarding atrial electrical activity and structure in patients with normal cardiac function.

Analysis of Dyssynchrony and Ventricular Function in Right Univentricular Stimulation at Different Positions

“…One of such studies showed that septal pacing not only did not correlate with LVEF worsening, but also had fewer atrial arrhythmias during the follow-up period [ 11 ] . It should be noted, however, that those patients had a lower percentage of RV pacing when compared to subjects in our study (50-60% vs. > 80%).…”

“…The clinical consequence of such changes manifest through worsening of left ventricular ejection fraction (LVEF) and, in some cases, heart failure (HF) symptoms. Once LVEF starts to fall, it leads to deterioration in quality of life, to an increase in atrial fibrillation burden and to a tendency to a higher mortality [ 7 - 11 ] . The DAVID trial [ 12 ] showed that RV pacing is poorly tolerated by patients and may cause heart failure.…”

Right Ventricular Septal Pacing: A Paradigm Shift

“…22 Zou et al assessed RVOT septal pacing in their retrospective analysis of 80 patients with complete AV block and normal cardiac function. 2 Patients who received either RVA pacing (n = 42) or RVOT septal pacing (n = 38) were included. 2 During two years of follow-up, six patients developed incident AF in the RVA pacing group, while only one patient with new-onset AF was observed in the RVOT septal pacing group.…”

“…2 Patients who received either RVA pacing (n = 42) or RVOT septal pacing (n = 38) were included. 2 During two years of follow-up, six patients developed incident AF in the RVA pacing group, while only one patient with new-onset AF was observed in the RVOT septal pacing group. Additionally, RVOT septal pacing resulted in a shorter QRS duration, intraventricular mechanical delay, and less left atrial volume increase as compared with RVA pacing.…”

“…1,2 However, long-term RV apical (RVA) pacing has been shown to have negative effects on ventricular function and hemodynamics as a result of ventricular dyssynchrony. 3 In the last decade (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010), more data have emerged on the association of RVA pacing and left ventricular (LV) systolic dysfunction, heart failure (HF), ventricular remodeling, atrial fibrillation (AF), and increased mortality.…”