Clinical impact of an additional left ventricular lead in cardiac resynchronization therapy nonresponders: The V 3 trial.

Background: 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 (V ³ CRT) may improve clinical status of CRT nonresponders.
Objective: We assessed the feasibility and safety of adding a second LV lead to CRT nonresponders and its clinical impact.
Methods: 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 V ³ 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.
Results: Positioning of a second LV lead was successful at first (40 of 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 V ³ 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.
Conclusion: 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).
(Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)