Safety, feasibility, and outcome results of cardiac resynchronization with triple-site ventricular stimulation compared to conventional cardiac resynchronization.

Background: The nonresponder rate to cardiac resynchronization therapy (CRT) may be due to incomplete resynchronization, with dyssynchrony persisting in approximately 30% of patients. We hypothesized that CRT with triple-site ventricular stimulation (TRIV) may improve resynchronization and its outcomes.

Objective: The purpose of this study was to assess the feasibility and safety of TRIV and collected data on clinical outcomes to dimension future studies.

Methods: Our pilot randomized trial was designed to assess the safety and feasibility of TRIV with 2 right ventricular leads and 1 left ventricular leads compared to conventional CRT. The primary end-point was the rate of severe adverse events at 6 months. Secondary end-points included functional improvement parameters, quality-of-life (QOL) score, and changes of echocardiographic indices at 6 and 12 months in a subset of patients.

Results: Seventy-six patients were enrolled at 11 centers and randomized to control or TRIV arm. All implant procedures but one were successful. At 6 months, there was no statistical difference between proportions of patients with at least 1 severe adverse event in both groups (34.1% vs 25.7%, P = .425). There also was no difference between functional improvement parameters, 6-minute walking distances (P = .40), QOL scores (P = .27), and echographic indices. At 12 months, the proportions of patients with a left ventricular ejection fraction gain of more than 5%, 10%, or 15% were significantly superior with TRIV.

Conclusion: TRIV pacing is an effective and safe technique and may provide a greater benefit in ventricular remodeling than conventional CRT. Further studies are needed to assess its long-term benefit.