Design and rationale of the atrial fibrillation occurring transiently with stress (AFOTS) follow-up cohort study.

Atrial fibrillation occurring transiently with stress (AFOTS) describes the first detection of AF in a patient who is hospitalized for a non-cardiac medical illness or following non-cardiac surgery. Uncertainty exists whether episodes of AFOTS are due to reversible precipitants and will not recur after recovery, or if they are paroxysmal atrial fibrillation (AF) that is detected during inpatient cardiac monitoring. Previous studies have used retrospective, non-systematic and ultimately low-sensitivity protocols to investigate the recurrence of AF in patients with AFOTS.