Occult etiologies of complete atrioventricular block: Report of two cases

In patients presenting with complete atrioventricular (AV) block, the common causes are degeneration of the conduction system, acute myocardial infarction, congenital and metabolic disorders (such as azotemia). However, at times, no cause can be ascribed and the label congenital or degenerative is applied depending on the patient's age and the QRS complex width. We present two cases of patients with complete AV block, who were subsequently found to have rare etiologies - sarcoidosis (with isolated feature of AV block) and non-Hodgkin's lymphoma.