患者,男,5 7岁。以反复心前区疼痛3年、加重1d入院。该患者3年来多于劳累时出现心前区闷痛,每次1 0min余,休息或含服硝酸甘油3～5min可缓解,此次因反复再发心前区疼痛,持续2h伴大汗,含服硝酸甘油不缓解入院。患者否认高血压史。入院体检除心率慢( 4 0～45次/min)外,余无阳性体 Patient, male, 57 years old. Repeated precordial pain for 3 years, increased 1d admission. The patient more than 3 years before exertional heart area before boring, every 10min, rest or sublingual nitroglycerin 3 ~ 5min can ease, the recurrence of precordial pain due to repeated, sustained 2h with sweating, Nitroglycerin does not relieve admission. Patients denied history of hypertension. In addition to physical examination admitted to the heart rate is slow (40 ~ 45 times / min), I no positive body