Clinical impact of an additional left ventricular lead in cardiac resynchronization therapy nonresponders: The V3 trial

Abstract

Cardiac resynchronization therapy (CRT) is an effective treatment of heart failure (HF), but is limited by a substantial proportion of nonresponders. We hypothesized that adding a second left ventricular (LV) lead to deliver a triple-site CRT (V3 CRT) may improve clinical status of CRT nonresponders. We assessed the feasibility and safety of adding a second LV lead to CRT nonresponders and its clinical impact. Eighty-four recipients of a CRT system and considered as nonresponders as per clinical composite score (CCS) were enrolled in this multicenter study. They were randomized to the V3 arm (implantation of an additional LV lead; n = 43) or control arm (no change; n= 41). Implant success rate, incidence of severe adverse events, CCS, and secondary clinical and echocardiographic end points were evaluated at 12 and 24 months. Positioning of a second LV lead was successful at first (40of 44 - 90.9%) or second (4 of 44 - 9.09%) attempt. The perioperative complication rate (infection, system explant, pneumothorax, and hematoma) was high (procedures or system-related complications for 9 patients- 20.4%). After 24 months, 35 systems (79.5%) were working properly. The multinomial logistic regression model showed that V3 treatment had no significant influence (P = .27) on the CCS, number of HF hospitalizations, time to first HF hospitalization, New York Heart Association class, and LV ejection fraction at 12 and 24 months. Although addition of a second LV lead in CRT nonresponders is feasible with a high success rate, this approach is associated with a significant rate of severe adverse events and does not provide significant long-term clinical benefits (ClinicalTrials.gov Identifier No. NCT01059175).