Idiopathic familial atrial cardiomyopathy with diffuse conduction block.

Isolated atrial cardiomyopathy is rare and familial idiopathic atrial cardiomyopathy has only been described once. We describe a case characterized by severely reduced atrial contractile function, intermittent atrial electrical standstill, diffuse interatrial, intraventricular and atrioventricular block, complicated by systemic embolism. Whilst this condition is undoubtedly rare, other cases may be being mistaken for simple sinoatrial disease.