The Use of a Quadripolar Left Ventricular Lead Increases Successful Implantation Rates in Patients with Phrenic Nerve Stimulation and/or High Pacing Thresholds Undergoing Cardiac Resynchronisation Therapy with Conventional Bipolar Leads

• Main Authors: Marc-Alexander Ohlow, MD, Bernward Lauer, PhD, Michele Brunelli, PhD, Yunis Daralammouri, MD, J. Christoph Geller, PhD
• Format: Article
• Language: English
• Published: Elsevier 2013-03-01
• Series: Indian Pacing and Electrophysiology Journal
• Subjects: Threshold; phrenic nerve stimulation; quadripolar; lead; cardiac resynchronisation therapy
• Online Access: http://www.sciencedirect.com/science/article/pii/S0972629216306052

Background: Phrenic nerve stimulation (PNS) and high pacing thresholds (HPT) hinder biventricular stimulation in patients (pts) undergoing cardiac resynchronization therapy (CRT). A new quadripolar left ventricular (LV) lead (Quartet 1458Q, St. Jude Medical) with increased number of pacing configuration, might overcome this problem. Methods: All consecutive pts in whom a standard bipolar lead intraoperatively resulted in PNS and/or HPT (≥4.00 V/1 mV), received, during the same implant, a quadripolar LV lead. Aim of the study was to evaluate acute and short term outcome. Results: 26 pts [24 (92%) male, mean age 74±6 years)] with PNS (22 pts; 85%) and HPT (4 pts; 15%) were included. Permanent right ventricular pacing was the reason for broad QRS complex in 4 (15%) pts, whereas all other pts had a left bundle branch block. Severely symptomatic (NYHA Class ≥3) heart failure with reduced ejection fraction (EF 31±9%) was mostly caused by ischemic heart disease (14 pts; 54%). Idiopathic dilated cardiomyopathy and valvular heart disease were diagnosed in 6 (23%) pts each. In most (24/26, 92%) pts the use of the Quartet lead led to successful biventricular pacing due to a significant reduction in intraoperative pacing threshold (5.2 V/1.0 ms vs. 1.4 V/0.8 ms; p=0.03), which was maintained (1.2 V/0.7 ms) at follow-up. PNS never represented reason for failed LV pacing, neither acutely nor during follow-up. Conclusions: Excessively HPT and/or PNS are frequently encountered when conventional bipolar leads are used for CRT. A new quadripolar LV lead increases the rate of successful biventricular stimulation. Lower pacing threshold and freedom from PNS are maintained at follow-up.