A case of prolonged asystole during head-up tilt testing.

Head-up tilt test is used for assessing patients with vasovagal syncope. A 45-year-old man was examined for two syncopal and three presyncopal episodes during the past three months, all of which preceded by nausea and sweating. Examinations including electrocardiography and echocardiography showed normal findings. A head-up tilt table testing was performed at an angle of 75 degrees. At about 12 minutes, syncope associated with bradycardia and asystole was observed. He became hypotensive, and there was a ventricular asystolic pause lasting 18 seconds, associated with loss of consciousness. He was placed in the supine position and cardiac massage was started. After 25 seconds, he slowly returned to sinus rhythm and regained consciousness. The patient was treated with dual-chamber pacemaker implantation. During one year of follow-up, no major events occurred.