Study Subjects
Patients with early onset familial AF, including a multiplex Lebanese family with early onset familial AF, cardiomyopathy, and heart block requiring pacemaker placement were referred to the Yale Cardiovascular Genetics clinic for genetic screening. All other kindreds had isolated AF with no structural heart disease. The protocol was approved by the institutional review board at Yale University School of Medicine. Informed consent to participate in the study and to undergo genetic sequencing was obtained from all patients. Detailed clinical information, including laboratory data and clinical imaging were collected. Genomic DNA was extracted from peripheral blood leukocytes and sent for exome sequencing. Family history was obtained from the index cases, and pedigrees were constructed based on self-reported phenotypes.