Case report: third-degree atrioventricular block secondary to septic coronary artery embolism following infective endocarditis

Coronary artery emboli can occur from a number of rare causes such as arterial thrombo-embolus or septic embolus. This diagnosis generally requires multi-modal imaging including echocardiography, computed tomography, or invasive coronary angiography. Septic coronary emboli is an extremely rare consequence of infective endocarditis (IE), having been reported in <1% of all cases.

A 54-year-old previously healthy Tibetan monk presented feeling generally unwell and lethargic. Electrocardiogram demonstrated sinus rhythm, third-degree atrioventricular block with a left bundle branch escape. Initial transthoracic and transoesophageal echocardiography demonstrated vegetations on the aortic and tricuspid valve as well as intra-myocardial abscess. Coronary angiography revealed septic embolus involving the septal perforator coronary artery. He underwent surgical replacement of the infected valves and debridement and repair of a ventricular septal defect.

Infective endocarditis can predispose to a range of cardiac pathology. This case demonstrates that patients can present with cardiac conduction disease from a septic embolus involving a coronary artery as a complication of IE.