Hydatid cyst of the cardiac interventricular septum with complete atrioventricular block: a case report from Pakistan.

Cardiac involvement in systemic echinococcosis is a rare phenomenon. Abnormalities of the cardiac conduction system are an exceptional feature of cardiac hydatidosis. We report, to the best of our knowledge, the first case of cardiac hydatidosis from Pakistan in a 30 year old male who presented with recurrent syncopal episodes due to complete atrioventricular conduction block and subsequently underwent implantation of dual chamber pacemaker. His transthoracic echocardiogram revealed a large, well circumscribed, interventricular septal mass which was avascular on subsequent perfusion imaging. Surgical resection of the mass three years later confirmed it to be a hydatid cyst.