Ghani M F, Rabah M
Am Heart J. 1977 Nov;94(5):600-2. doi: 10.1016/s0002-8703(77)80129-4.
The effect of magnesium chloride on the ventricular fibrillation threshold (VFT) and the threshold for the ventricular premature contraction (VPCT) was studied in 20 dogs. Seven of the dogs were pre-treated with digitalis and four were in the form of heart-lung preparations. In the anesthetized, intact dogs, the VPCT was 0.19 +/- 0.01 mV. After treatment with magnesium chloride (100 mg. per kilogram intravenously), the VPCT increased by 53% (P less than 0.01). In the same group of animals, the VFT averaged 0.50 +/- 0.06 mV., which more than doubled after administration of magnesium. The threshold of VPC in the digitalis-treated dogs measured 0.18 +/- 0.01 mV; this value doubled after magnesium. The VFT in the digitalized dogs also increased after magnesium; however, resistance to electrical defibrillation was encountered in this group. In the heart-lung preparations, VPCT improved by 72% and a gain of 131% in the VFT followed magnesium administration. The results suggest that magnesium increases the ventricular threshold of arrhythmias in normal, denervated (heart-lung preparations) and also digitalis-treated hearts and, thus, indicate its usefulness in the treatment of ventricular arrhythmias.
在20只狗身上研究了氯化镁对心室颤动阈值（VFT）和室性早搏阈值（VPCT）的影响。其中7只狗预先用洋地黄治疗，4只制成心肺标本。在麻醉的完整狗中，VPCT为0.19±0.01mV。静脉注射氯化镁（每公斤100毫克）后，VPCT增加了53%（P<0.01）。在同一组动物中，VFT平均为0.50±0.06mV，给予镁后增加了一倍多。洋地黄治疗的狗的室性早搏阈值为0.18±0.01mV；给予镁后该值翻倍。洋地黄化的狗给予镁后VFT也增加；然而，该组出现了对电除颤的抵抗。在心肺标本中，给予镁后VPCT提高了72%，VFT增加了131%。结果表明，镁可提高正常、去神经（心肺标本）和洋地黄治疗的心脏的心律失常心室阈值，因此表明其在治疗室性心律失常方面的有用性。
