Introduction: Frequent right ventricular (RV) apical pacing was shown to have deleterious effects on left ventricular function and – therefore.- may negatively influence morbidity and mortality in patients implanted with permanent pacemakers (PM). The potential benefit of non-apical RV lead placement on mortality of patients implanted with permanent PM remains unclear. The purpose of our study was to compare mortality of patients implanted with PM and who had different RV lead positions.
Methods: Mortality was retrospectively analyzed in all patients implanted with permanent single and dual chamber PM at our department between Jan 2009 and Dec 2011. RV lead position (apical [position#1], septal/mid-septal [position#2], high septal [position#3], RVOT [position#4]) was assessed by reviewing either implantation reports and/or fluoroscopic lead documentation at implantation or thereafter. Fatal events were retrieved from the Statistical Department of the Austrian government (observational period until Dec 31, 2011). Categorial variables were compared using the chi-square, and Fisher`s exact test, where appropriate. Kaplan-Meier survival curves using the log rank test were calculated for survival for the different lead positions. Multivariate analyses were performed using Cox regression. A p-value < 0.05 for two-sided comparisons was considered statistically significant.
Results: Within the observational period 782 patients (female 353 [45%], mean age 77±10 years, AV block 2nd and 3rd degree 43%, sick sinus syndrome 24%, single chamber PM 195 [25%], RV lead position #1/#2/#3/#4 562 [72%]/65 [8%]/38 [5%]/117 [15%]) were implanted with PM. The mean follow-up duration was 445±302 days. Within the observational period 97 patients (12%) died. There was no difference in mortality with respect to RV lead position (all-cause mortality pos#1/#2/#3/#4: 75 [13%]/9 [14%]/3 [8%]/10 [9%], log-rank=ns; cardiovasc. mortality pos#1/#2/#3/#4: 42 [8%]/3 [5%]/2 [5%]/6 [5%], log-rank=ns). Cox regression analyses revealed an age > 80 years, a history of renal insufficiency and stroke, but not RV lead position to be predictive for death after permanent PM implantation.
Conclusions: In this standard PM patient cohort non-apical RV lead positions had no beneficial effect on all-cause and cardiovascular mortality when compared with apical lead position.