Long-Term Results of Triventricular Versus Biventricular Pacing in Heart Failure: A Propensity-Matched Comparison.

Objectives: The goal of this study was to assess the impact of triventricular pacing (Tri-V) on long-term survival.

Background: Biventricular pacing (Bi-V) is an important adjunctive treatment in advanced heart failure, but almost one-third of patients experience no improvement with this therapy and are labeled as nonresponders. Adding a third ventricular lead (Tri-V) has been shown to be feasible and provides favorable acute results when assessed by using echocardiographic, hemodynamic, and clinical endpoints. However, the long-term effects of Tri-V pacing and how it affects long-term survival remains unknown.

Methods: This single-center, propensity score-matched cohort study compared 34 patients with advanced heart failure who underwent implantation with Tri-V devices versus 34 control subjects treated with Bi-V pacing. Clinical outcomes during a median of 2,478 days (IQR: 1,183 to 3,214 days) were compared.

Results: Tri-V-treated patients compared with Bi-V-treated patients presented with a trend for shorter battery longevity (time to box change, 1,758 ± 360 days vs. 1,993 ± 408 days; p = 0.072). Incidence of lead dislodgement (Tri-V vs. Bi-V, 0.86 vs. 1.10 per 100 patient-years; p = 0.742), device-related infection (Tri-V vs. Bi-V, 1.83 vs. 1.76 per 100 patient-years; p = 0.996), and refractory phrenic nerve capture (Tri-V vs. Bi-V, 0.48 vs. 1.84 per 100 patient-years; p = 0.341) was comparable in the 2 groups. Episodes of ventricular arrhythmia requiring implantable cardioverter-defibrillator intervention occurred more frequently in the Bi-V group versus the Tri-V group (6.55 vs. 16.88 per 100 patient-years; adjusted hazard ratio: 0.31; 95% confidence interval: 0.14 to 0.66; p = 0.002). Lower all-cause mortality and heart transplant was observed in the Tri-V group compared with the Bi-V group (6.99 vs. 11.92 per 100 patient-years; adjusted hazard ratio: 0.44; 95% confidence interval: 0.23 to 0.85; p = 0.015).

Conclusions: Tri-V displayed a similar safety profile compared with Bi-V and was associated with potential benefits regarding long-term survival and ventricular arrhythmia burden.