As there is a paucity of clear data on the influence of atrial fibrillation (AF) on clinical course and outcome in hypertrophic cardiomyopathy (HCM), a study published in the Circulation journal was conducted to determine the same. It was suggested that transient symptomatic episodes of AF, often responsible for reduced quality of life, are unpredictable in frequency and timing. However, they are amenable to effective contemporary therapies, and infrequently progress to permanent AF. AF is not considered a major contributor to heart failure morbidity or a cause of arrhythmic sudden death. When treated, it is associated with low disease-related mortality, similar to that for patients without AF. AF is not a common primary cause of death in HCM.