Exercise-induced ventricular tachycardia associated with asymptomatic Brugada syndrome in a patient with urinary bladder stone.

It is well-known that autonomic nerve modulation has an important role in the occurrence of ventricular tachyarrhythmias in Brugada syndrome. A 59-year-old man underwent cardiac evaluation before surgery for urinary bladder stone. He had no cardiac complaints and the only coronary risk factor was heavy smoking. The electrocardiogram showed a saddleback type ST-segment elevation in leads V1-V2, and left axis deviation. During exercise stress test, ventricular tachycardia with a left bundle branch block pattern appeared, and the saddleback type ST-segment elevation in V2 changed into a coved-type ECG at the recovery phase. The ventricular tachycardia was hemodynamically stable and normalized without medication. An echocardiogram showed normal left and right ventricular functions, and subsequent coronary angiography revealed normal coronary arteries. Based on these findings, a diagnosis of asymptomatic Brugada syndrome was made. Considering this particular case, it can be speculated that bladder-cardiac reflex may stimulate the autonomic nervous system via the vagus nerve and unmask Brugada syndrome.