Atrial fibrillation burden during the post-implant period after crt using device-based diagnostics.

Aims: Cardiac resynchronization therapy (CRT) is increasingly used in congestive heart failure (CHF) patients (with cardiac dyssynchrony). In addition to delivering therapy, CRT devices offer a variety of diagnostic tools for continuous long‐term monitoring of clinically relevant information (i.e., occurrence and duration of arrhythmia episodes).

Methods and Results: Eighty‐four patients with drug‐refractory CHF in NYHA‐class II–IV received a CRT device. The response to CRT was assessed by determining NYHA class at baseline and at 3 months follow‐up. Atrial fibrillation (AF) burden (defined as time of AF per day) was continuously measured by the device. A significant gradual reduction of AF burden (from 9.88 ± 12.61 to 4.20 ± 9.24 [hours/day]) and number of patients experiencing AF episodes (from 26 to 13) were observed during CRT.

Conclusions: (1) Diagnostic features for long‐term monitoring of physiological variables provide useful information on the state and course of AF and may improve disease management. (2) AF burden reduces over time during the first 3 months after CRT implantation.