Left ventricular pacing with a new quadripolar transvenous lead for CRT: Early results of a prospective comparison with conventional implant outcomes

BACKGROUND: Flexible left ventricular (LV) pacing configurations are a useful component of cardiac resynchronization therapy (CRT) systems for preventing high LV pacing thresholds and phrenic nerve stimulation (PNS). A quadripolar LV lead has recently been designed with the purpose of allowing more choices in lead placement location and programming capability. OBJECTIVE: To verify the effectiveness of quadripolar LV leads compared to conventional bipolar LV leads implant outcomes. METHODS: Forty-five consecutive patients underwent implantation with either the quadripolar (n = 22; quadripolar group) or a conventional bipolar LV lead (n = 23; bipolar group). The primary outcome of the study was LV lead failure, defined as the need for lead revision or reprogramming during the first 3 months after implantation. Additionally, operative and follow-up data were prospectively noted and checked for significance between groups. RESULTS: The implantation success rate in both groups was 100%. Baseline characteristics, procedure duration, and fluoroscopy time did not differ significantly between groups. Two lead dislodgments (requiring reoperation) and 4 clinical PNS were reported in the bipolar group; reprogramming of the device was sufficient to prevent PNS in 3 patients, the fourth is pending solution. One PNS successfully managed noninvasively occurred in the quadripolar group. By Kaplan-Meier analysis, event-free survival for the combined primary outcome was significantly lower in patients with quadripolar leads (P = .037). CONCLUSION: This prospective, controlled study provides strong evidence that CRT with the quadripolar LV lead results in low rates of dislocations and phrenic nerve stimulation.