A 44-year-old man presented to our emergency room with a history of chest tightness, vertigo, and nausea, along with episodes of syncope. Physical examination revealed severe bradycardia of 30 bpm and blood pressure of 98/60 mmHg, and the electrocardiographic monitor showed complete atrioventricular block (Figure, Panel A). There was no history of chest trauma, fever, or exposure to sexually transmitted diseases, and he did not have a marfanoid appearance. Complete hemogram and biochemical parameters were within normal limits.