[Localization of isolated atrial involvement of cardiac sarcoidosis]

The authors report the first case of cardiac sarcoidosis involving only the interatrial septum and the atrioventricular node in a 30 year old man with known lymph node sarcoidosis. The diagnosis was suspected after the finding of an apparently innocent 1st degree atrioventricular block and confirmed by transoesophageal echocardiography and by IMATRON computerised tomography. Isolated atrial involvement of sarcoidosis is rare in the absence of any left ventricular disease. This explains the negative findings at transthoracic echocardiography and radio-isotopic investigations usually recommended for diagnosing cardiac sarcoidosis.