Effect of Rate-responsive Compared to VDD Pacing in Cardiac Resynchronization Therapy Recipients

This study aims to understand the best programming pacing mode for cardiac resynchronization therapy devices used to treat chronic heart failure.

Cardiac resynchronization therapy (CRT) efficacy trials to date used atrial-synchronous biventricular pacing wherein there is no or minimal atrial pacing. However, bradycardia and chronotropic incompetence are common in this patient population. Despite neutral results on hard clinical outcomes of the atrial support in CRT patients, it is not clear if a rate-responsive pacing may add incremental benefits on exercise capability. The aim of this study is to assess the impact of RR pacing compare to VVD pacing in patients implanted with CRT devices in term of functional capacity, measured by the six-minute walking test (6MWT). This simple test has shown to be an independent predictors of mortality in this cohort of patients.