Intracoronary and Intravenous Magnesium Does Not Reduce Myocardial Infarct Size in a Canine Model of Regional Ischaemia and Reperfusion

Journal of Clinical and Basic Cardiology

Schlack W¹  Grunert S¹  Thämer V¹  Ebel D¹ 

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关键词: Herz;    Hund;    Infarktgröße;    Ischämie;    magnesium;    Myokardinfarkt;    reperfusion;    dog;    heart;    infarct size;    ischaemia;    magnesium;    myocardial infarction;    reperfusion;   

DOI  :  

学科分类：心脏病和心血管学

来源: Krause & Pachernegg GmbH

【 摘 要 】

Clinical trials show controversial effects of magnesium infusion in patients with acute myocardial infarction. In LIMIT-2, intravenous magnesium lowered mortality, but in the much larger ISIS-4, intravenous magnesium had no effect. Because of these conflicting results, we tested two hypotheses in a dog model of ischaemia and reperfusion. A) Intracoronary magnesium infusion given in the early reperfusion period has a protective effect against myocardial reperfusion injury. B) Systemic magnesium-potassium infusion with doses comparable to those used in clinical studies, may reduce myocardial infarct size.Anaesthetized open chest dogs underwent 1 h of left anterior descending artery occlusion followed by 6 h of reperfusion. A) Animals received intracoronary magnesium aspartate (Mg i.c., n = 5) or vehicle infusion (Control i.c., n = 5) for the first hour of reperfusion to increase regional plasma concentration by 4 mmol l?1.B) Animals received intravenous magnesium-potassium-aspartate (Mg-K i.v., n = 6) or vehicle infusion (Control i.v., n = 8) beginning 1 h before occlusion until the end of the 6 h reperfusion period. Intracoronary magnesium had no influence on infarct size (Mg i.c. 20.6 ± 5.0 % of area at risk, Control i.c. 24.4 ± 8.7 % of area at risk, P = ns) or regional post-ischaemic wallfunction. Application of intravenous magnesium-potassium did not reduce myocardial infarct size (Mg-K i.v. 14.1 ± 14.8 %; Control i.v. 18.1 ± 12.2 % of area at risk; P = ns). The possible beneficial effect of magnesium infusion is probably not due to an early, direct protective effect on ischaemic-reperfused myocardium.

【 授权许可】

Unknown