Norbert Klein, Dietrich Pfeiffer, Maika Klein
Background/Aims: It has previously been shown that permanent right ventricular (RV) apical pacing may lead to worsening of cardiac function due to associated electrical and mechanical dyssynchrony. Cardiac resynchronization therapy (CRT) or high septal RV pacing could be beneficial to prevent patients from these negative effects.
Methods/Results: In this single center clinical study 164 patients with permanent ventricular pacing indication, but without CRT indication, were assigned to three groups based on pacing location: RV apical pacing (RV apical; n=62), biventricular pacing (BiV; n=60) and RV high septal pacing (RV septal; n=42). Study objectives were procedural burden (procedure and fluoroscopy time) and electrical lead performance over two years follow up. The BiV-group had the longest implant duration (64.9 ± 0.3 min) and fluoroscopy time (13.8 ± 10.9 min; p<0.05 to RV apical and RV septal). The implant duration was similar (p=ns) in RV apical (36.0 ± 10.1min.) and RV septal group (40.1 ± 19.1 min.) as well as fluoroscopy time (4.3 ± 5.5 min vs 4.0 ± 3.6 min; p=ns). Acute RV septal sensing was lower [7.8 ± 3.4 mV vs 17.5 ± 20.8 mV (RV apical) and 14.2 ± 7.1 mV (BiV), p<0.05], RV-pacing thresholds were higher (0.7 ± 0.3V/0.5 ms vs 0.5 ± 0.2V/0.5 ms and 0.4 ± 0.1V/0.5 ms, p<0.05) and pacing impedance was lower (555 ± 73 Ω vs 774 ± 169 Ω and 821 ± 178 Ω, p<0.05). This difference maintains during long-term follow-up.
Conclusions: High septal placement of RV pacing leads creates no additional procedural burden for patients and despite slightly worse electrical performance overall, maintains acceptable performance over the long term. Considering the potential for adverse outcomes from RV apical pacing and the risks associated with CRT, we suggest that RV septal placement may be considered for patients with permanent ventricular pacing requirement.
