Tzivoni D, Keren A, Cohen A M, Loebel H, Zahavi I, Chenzbraun A, Stern S
Am J Cardiol. 1984 Feb 1;53(4):528-30. doi: 10.1016/0002-9149(84)90025-0.
This is the first report of the successful use of magnesium sulfate (MgSO4) in 3 consecutive patients with torsades de pointes (TdP). In 1 patient, TdP was induced by a combination of quinidine and amiodarone, in the second by procainamide, and in the third by an overdose of imipramine. The QT intervals before TdP were 0.70, 0.64 and 0.56 second, respectively. A bolus of 1.0 to 2.0 g MgSO4 25% abolished the TdP in all 3 patients; but in the third patient, because of recurrent TdP, a second bolus of 1.0 g and a continuous 24-hour infusion of 1.0 mg/min were administered, preventing TdP. There was no immediate shortening in the QT interval in any patient after MgSO4. Magnesium can be given safely even in patients with acute myocardial infarction, angina pectoris or systemic hypertension, conditions in which isoproterenol is contraindicated; it can be applied faster than temporary cardiac pacing; and its use for TdP appears worthy of additional trials.
这是首次关于连续3例尖端扭转型室速（TdP）患者成功使用硫酸镁（MgSO4）的报告。1例患者的TdP由奎尼丁和胺碘酮联用诱发，第2例由普鲁卡因胺诱发，第3例由过量服用丙咪嗪诱发。TdP发作前的QT间期分别为0.70秒、0.64秒和0.56秒。静脉推注25%硫酸镁1.0至2.0克使所有3例患者的TdP终止；但在第3例患者中，由于TdP复发，又推注了1.0克硫酸镁，并持续24小时以1.0毫克/分钟的速度静脉输注，从而预防了TdP发作。使用硫酸镁后，任何患者的QT间期均未立即缩短。即使是急性心肌梗死、心绞痛或系统性高血压患者（这些情况下禁忌使用异丙肾上腺素），也可安全使用硫酸镁；其应用速度比临时心脏起搏更快；并且其用于TdP似乎值得进一步试验。
