An unexpected presentation of sick sinus syndrome: Isolated ventricular asystole.

Sick sinus syndrome is a disorder of sinus node function characterized by various dysrhythmias such as sinus bradycardia or pause, paroxysmal regular or irregular atrial tachycardia, tachycardiabradycardia attacks or atrial fibrillation with slow ventricular response. Ventricular asystole with preserved atrial electrical activity is a rarely seen presenting rhythm in the ED and an extremely rare cause of syncope. A 67-year-old male having a syncope attack was admitted to the emergency department.