Improved implant and postoperative lead performance in CRT-D patients implanted with a quadripolar left ventricular lead. A 6-month follow-up analysis from a multicenter prospective comparative study.

Purpose: Small single-center comparative studies suggest improved outcomes in cardiac resynchronization therapy (CRT) patients implanted with a quadripolar left ventricular (LV) lead in comparison with non-quadripolar (bipolar) leads. This study represents the first large multicenter prospective registry comparing implant and 6-month postoperative lead performance following CRT-defibrillator (CRT-D) implantation with quadripolar vs. bipolar leads.

Methods: During a 39-month period, 418 consecutive patients having CRT-D implantation attempts with either a quadripolar (n = 230) or bipolar LV lead (n = 188) were enrolled in the registry. The primary outcome of the study was LV lead failure defined as any abnormality, excluding infection, resulting in surgical lead revision or CRT termination. Additionally, operative and follow-up data were analyzed for significant difference between groups.

Results: Baseline characteristics of both groups were similar. In 72.9 % of quadripolar leads versus 65.0 % of bipolar leads, the LV lead successfully engaged the predefined ideal target side branch (p = 0.47). Implant duration and fluoroscopy times were significantly shorter when a quadripolar lead was used (p = 0.007 and p = 0.001, respectively). The primary end point occurred in six patients (2.7 %) in the quadripolar group and in 14 patients (8.0 %) in the bipolar group (p = 0.02). Clinically significant phrenic nerve stimulation (PNS) occurred in 4.6 vs. 14.2 % of quadripolar vs. bipolar patients, respectively (p = 0.002); all PNS were resolved noninvasively through programming in the quadripolar group vs. 84 % in bipolar group (p = 0.75). The use of a bipolar lead was associated with a higher risk of surgical LV lead revision (6.3 vs. 2.3 %; p = 0.057) and a higher incidence of dislodgment (5.7 vs. 2.7 %; p = 0.16).

Conclusions: This multicenter study demonstrates that the use of a quadripolar LV lead results in significantly lower rates of lead-related problems and reduced procedural and fluoroscopic times for biventricular system implantation. This has important implications for LV pacing lead choice.