Circulation, Ahead of Print. Background: The role of atrial pacing support is unclear in cardiac resynchronization therapy-defibrillator (CRT-D) patients without sinus node dysfunction.Methods: We conducted a randomized, parallel-group, non-inferiority trial to evaluate whether a two-lead CRT-DX system capable of atrial sensing (but no pacing) via a floating dipole on the right ventricular lead is not inferior to a three-lead CRT-D with conventional atrial lead.
Between October 17, 2018, and March 5, 2024, 636 patients (68 ± 10 years old, 28.6% females) with standard CRT-D indication, optimized medical therapy, and resting sinus rate ≥45 beats/min were randomized 1:1 to CRT-DX (VDD 35 beats/min) or CRT-D (DDD 50 beats/min) at 23 Italian sites. A centralized block randomization procedure stratified by site was used, with patients and primary outcome assessors blinded to treatment assignment.
The primary endpoint was a 1-year composite of all-cause mortality, cardiovascular hospitalization, and lead-related complications (loss of functionality not correctable by device reprogramming).
Circulation published a clinical update in Cardiology on 30 Mar 2026.
The item focuses on The Role of Atrial Pacing Support in Cardiac Resynchronization Therapy: A Non-Inferiority Randomized Trial.
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