Mutations in theOne-hundred and one consecutive patients with "lone AF" criteria were initially screened by genetic testing. Genetic variants were classified according to the American College of Genetic and Genomic criteria. All subjects were evaluated through clinical and familial history, ECG, 24-h Holter monitoring, echocardiogram, cardiac magnetic resonance, treatment response, and the present relatives ofThree missense variants inAlthough a rare occurrence, our findings emphasize the possibility of an initial presentation of apparently "lone AF" in