Clinical outcomes after implantation of quadripolar compared to bipolar left ventricular leads in patients undergoing cardiac resynchronization therapy: a systematic review and meta-analysis

Aims Some retrospective and prospective studies in heart failure patients with indication for cardiac resynchronization therapy (CRT) suggest better clinical outcomes for quadripolar (QP) left ventricular (LV) leads over bipolar (BP) leads. Although, lead failure remains an important safety concern, when using these more complex, novel electrodes. To evaluate safety and efficacy outcomes for QP vs. BP LV leads in patients receiving CRT. Methods and results We performed a comprehensive literature search through 2018 in PubMed, Cochrane Library, and Google Scholar databases to identify studies comparing patients with QP and BP LV CRT leads. A total of 12 studies were selected for analysis comprising 31 403 patients (QP lead: 22 429 patients; BP lead: 8974 patients). Eight studies examined the effects of CRT on survival. In these studies, use of QP electrodes was associated with significantly better survival compared to patients with BP LV leads (OR 0.61, 95% CI 0.50-0.76; P<0.01). Clinical improval measured in New York Heart Association functional class (OR 0.59, 95% CI 0.34-1.01; P=0.05) and hospitalization rates (OR 0.67, 95% CI 0.55-0.83; P<0.01) were also improved in patients receiving QP leads. Lead malfunctions defined as LV lead failure resulting in lead deactivation (OR 0.57, 95% CI 0.34-0.98; P=0.04) or LV lead dislodgement requiring LV lead replacement/repositioning (OR 0.48; 95% CI 0.31-0.75; P<0.01) were more often encountered among patients with BP leads compared to patients with QP leads. Conclusion Our meta-analysis suggests distinct benefits of QP over BP electrodes in patients undergoing CRT.