Outcomes of cardiac resynchronization therapy using left ventricular quadripolar leads

Background: Quadripolar left ventricular (LV) leads provide a more optimal pacing configuration for cardiac resynchronization therapy (CRT) than conventional bipolar leads. The objective of this study is to determine the clinical outcomes of CRT using quadripolar leads. Methods: This study included 516 CRT patients who received bipolar LV leads (n = 278) or quadripolar LV leads (n = 238) from January 2013 to June 2016. Data were retrospectively collected from a prospective CRT database and electronic health records. CRT response to CRT was defined as >5% improvement in the LV ejection fraction (LVEF) from baseline. Baseline characteristics and outcomes were compared between groups. Results: New York Heart Association Functional Classification and LVEF significantly improved in the quadripolar and bipolar groups after CRT. There was no difference in the all-cause mortality rate. The implant success rate was significantly higher in the quadripolar group (100% vs 97.8%; P = 0.02). Quadripolar lead placement was an independent predictor of CRT response at 12 months (hazard ratio, 0.76; 95% confidence interval, 0.58–0.98; P = 0.04). The rate of LV lead–related complications requiring invasive lead revision or abandonment was significantly higher in the bipolar group (11.2% vs 4.6%; P = 0.007). Conclusions: Quadripolar leads achieve similar CRT outcomes as bipolar LV leads but with a higher implant success rate and fewer procedure-related complications.