Atrial Fibrillation

The article by Halcox et al describes the REHEARSE-AF study (Assessment of Remote Heart Rhythm Sampling Using the AliveCor Heart Monitor to Screen for Atrial Fibrillation), a randomized trial of screening for atrial fibrillation (AF) with a smartphone-based single-lead electrocardiographic capture system in 1001 patients ≥65 years of age with a CHA2DS2-VASc score of ≥ 2 and without a history of AF. Patients were randomized either to biweekly electrocardiographic recordings with the iPhone device (iECG group; n=500) or to routine care (control group; n=501) over a 12-month period. Not surprisingly, more patients with AF were identified in the iECG group (n=19) than in the control group (n=5).The data from this study confirm results from studies with implanted pacemakers, cardioverter-defibrillators, and loop recorders and other AF screening studies that, in patients unknown to have AF, particularly those with cardiovascular comorbidities, the more we look for AF, the more we will find it. As Sophocles mused more generally, "Look and you will find-what is unsought will go undetected." But is there a need to know about asymptomatic episodes of so-called subclinical AF (SCAF)? What are the implications of such a finding?