Single-center experience of a quadripolar pacing lead for cardiac resynchronization therapy

Recent studies have shown that a quadripolar left ventricular (LV) lead can result in low rates of dislocation and phrenic nerve stimulation (PNS) acutely and on medium-term follow-up in cardiac resynchronization therapy (CRT). We evaluated the outcomes of CRT patients in whom a quadripolar LV lead was implanted in our institution. We studied 45 consecutive heart failure patients (75 % men; age, 70.3 +/- 9.0 years) following successful implantation of a quadripolar LV lead. Demographic and clinical data were collected preoperatively, and patients were followed up for 18.9 months. The implantation success rate was 100 %. Mean overall duration was 100.1 +/- 34.6 min, and X-ray exposure time was 13.20 +/- 13.5 min. The most distal effective pacing site was used as the final pacing configuration in all patients. Acute dislodgment requiring reoperation occurred before discharge in three cases (6.6 %). Six patients (13 %) suffered PNS during follow-up; we solved this problem by changing the stimulation vector. Three months after implantation, a mean of six out of ten effective sites (threshold < 2.5 V at 1.5 ms, no PNS) per patient was recorded. Over the relatively long term, the quadripolar LV lead was associated with excellent pacing thresholds and low rates of dislocation and PNS.