Outcome of Patients Treated by Cardiac Resynchronization Therapy Using a Quadripolar Left Ventricular Lead

Background: Not all heart failure (HF) patients benefit from cardiac resynchronization therapy (CRT). We assessed whether choosing the site of left ventricular (LV) pacing by a quadripolar lead may improve response to CRT. Methods and Results: We prospectively randomized 23 patients with HF (67+/-11 years; 21 males) to CRT with a quadripolar LV lead (group 1, with the LV pacing site chosen on the basis of QRS shortening using simultaneous biventricular pacing), and 20 patients (71+/-6 years; 16 males) to a bipolar LV lead (group 2, with devices programmed with a conventional tip-to-ring configuration). New York Heart Association (NYHA) class and LV ejection fraction (EF) by 2D echocardiography were assessed at baseline and after 3 months. The baseline EF was not different between the 2 groups (25+/-6% group 1 vs. 27+/-3% group 2; P=0.22), but after 3 months EF was higher in group 1 (35+/-13% group 1 vs. 31+/-4% group 2; P<0.001). A reduction in at least 1 NYHA class at 3 months was observed in 22 (96%) and 12 (60%) of group 1 and group 2 patients, respectively (P<0.05). Conclusions: CRT with a quadripolar LV lead was associated with an improvement of EF greater than that observed in patients receiving a bipolar LV lead. In devices with a quadripolar lead, CRT programming based on the best QRS shortening is reliable and effective.