Congenital Heart Defects, Multiple Types, 3, is also known as congenital heart defects, multiple types, with cardiac rhythm and conduction disturbances. An important gene associated with Congenital Heart Defects, Multiple Types, 3 is CHEK2 (Checkpoint Kinase 2). Affiliated tissues include heart, and related phenotypes are atrial septal defect and atrioventricular block