本文报告2例QT间期延长的病人,因低血钾症和应用乙胺碘呋酮引起室性快速心律失常而致晕厥。例1:女,49岁,二尖瓣狭窄作交界分离术,本次因晕厥住院。入院前3个月因室上性心律失常使用乙胺碘呋酮(600mg/d)治疗。入院前1个月,血钾正常,心电图示QTc间期延长(600ms)。进院前15天因有轻度高血压加用Clorthalidone每2天100mg,15天后发生“异常”的(类似双向性)室性快速心律失常而致晕厥。当即检查血清钾浓度为3.2mEq/L。停止乙胺碘呋酮治疗,静注慢心律转为窦性心律,QT/U间期显著延长(600ms),给静脉内补钾,迅速纠正低钾血症后,U波消失,但QTc间期在停用乙胺碘呋酮后10天才恢复正常(360ms), 例2:男性,53岁,曾有几次发作性心悸,但无 This article reports 2 patients with QT prolongation due to hypokalemia and amiodarone-induced ventricular tachyarrhythmia caused syncope. Example 1: Female, 49 years old, mitral stenosis for borderline isolation, the hospital for syncope. 3 months prior to admission due to supraventricular arrhythmias with amiodarone (600mg / d) treatment. One month before admission, serum potassium is normal, and QTc interval is prolonged (600ms). Fifteen days prior to admission, syncope resulted from “abnormal” (quasi-bidirectional) ventricular tachyarrhythmias with Clorthalidone given with mild hypertension plus 100 mg every 2 days after 15 days. Immediately check the serum potassium concentration of 3.2mEq / L. Stop amiodarone treatment, intravenous slow heartbeat into sinus rhythm, QT / U interval was significantly prolonged (600ms), to the intravenous potassium, potassium hypoxemia quickly corrected, the disappearance of U wave, but between the QTc The period returned to normal after 10 days of discontinuation of amiodarone (360 ms). Example 2: Male, 53 years old, had several episodes of palpitations but no