Transient complete heart block: a case report of a rare complication of tricuspid valve infective endocarditis

Background Right-sided tricuspid valve (TV) endocarditis can be difficult to identify and may be under-recognized in the absence of traditional risk factors. While generally identified with aortic valve pathology, infective endocarditis that extends beyond the leaflets of the TV have been reported to cause conduction disease. Case summary We present the case of a 63-year-old patient who presented with haemodynamically unstable complete heart block requiring temporary venous pacemaker support. Despite the absence of traditional risk factors or significant valvular disease on transthoracic echocardiogram, she was found to be persistently bacteraemic and subsequent transoesophageal echocardiogram identified large vegetation on the septal leaflet of the TV. Conduction disease was noted to reverse with antibiotic therapy and resolution of bacteraemia. Discussion Although rare, right-sided endocarditis involving the triangle of Koch may present with conduction disease due to local inflammation and mechanical compression. Conduction disease associated with right-sided disease appears to be readily reversible with medical therapy and temporary device support may be appropriate in the acute setting.