Atrial fibrillation and cardiac resynchronization therapy: the MASCOT study

Atrial fibrillation (AF) and congestive heart failure (CHF) share several characteristics and often coexist in the same patient. Both are responsible for significant morbidity and mortality, are increasing in prevalence, and are major sources of health expenditure. The Management of Atrial fibrillation Suppression in AF-HF COmorbidity Therapy (MASCOT) study is a European, single-blind, prospective, controlled, multicentre, randomized clinical trial designed to examine whether adding the AF Suppression Algorithm to cardiac resynchronization therapy (CRT) improves the prognosis of patients with CHF. The patients will be randomly assigned to a CRT-only group, with the AF Suppression algorithm programmed OFF (control group), versus a CRT+AF Suppression group, with the algorithm programmed ON (treatment group). The primary study endpoint is development of permanent AF, and secondary endpoints are safety of the AF Suppression algorithm, and evolution of multiple clinical variables over 24 months of follow-up. CRT combined with a refined atrial tachyarrhythmia prevention pacing algorithm may represent a major advance in the management of AF and CHF by electrical stimulation.