Abstract |
The effect of magnesium sulfate on ventricular refractoriness and its efficacy for torsade de pointes (TdP) were studied in nineteen dogs. After the administration of quinidine sulfate (30 mg/kg), TdP was induced by ventricular pacing in ten of 19 dogs (52.6%), polymorphic ventricular tachycardia in seven (36.8%), ventricular fibrillation in two (10.5%). Quinidine sulfate caused significant increases in QTc interval, ventricular effective refractory period (ERP) and dispersion of ERP(dERP), and decrease in ERP/QT. Magnesium sulfate significantly increased ERP (p less than 0.01), but it did not change QT interval, resulting in significant increasing of ERP/QT (0.41 +/- 0.05 to 0.61 +/- 0.05, p less than 0.01). It decreased dERP but not significantly. Magnesium sulfate prevented the induction of TdP in eight of 10 dogs (80.0%) (30 mg/kg in four and 60 mg/kg in four). In conclusion, magnesium sulfate has value as first aid therapy for drug-induced TdP. If patients have ischemic heart disease or hypertension, we recommend infusion of magnesium for the initial therapy of TdP.
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Authors | S Bando, H Yamamoto, A Nishikado, K Hamai, K Fujino, Y Nakaya, A Shinohara |
Journal | The Tokushima journal of experimental medicine
(Tokushima J Exp Med)
Vol. 37
Issue 3-4
Pg. 69-73
(Dec 1990)
ISSN: 0040-8875 [Print] Japan |
PMID | 2094063
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- Magnesium Sulfate
- Quinidine
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Topics |
- Animals
- Dogs
- Drug Evaluation, Preclinical
- Electric Stimulation
- Heart Ventricles
(drug effects)
- Magnesium Sulfate
(pharmacology)
- Quinidine
(administration & dosage)
- Torsades de Pointes
(drug therapy, prevention & control)
- Ventricular Function, Left
(drug effects)
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