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Mitochondrial function, oxygen extraction, epicardial S-T segment changes and tritiated digoxin distribution after reperfusion of ischemic myocardium.

J J Kane·M L Murphy·J K Bissett·N deSoyza·J E Doherty·K D Straub
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Abstract

This study examines the effect of 2 hours of reperfusion on transiently ischemic myocardium in pigs. Indexes of myocardial viability measured were mitochondrial function, oxygen extraction, epicardial S-T segment change and distribution of tritiated digoxin. Results were as follows: (1) Mitochondrial function was markedly impaired in the reperfused area after 60 minutes or more of coronary occlusion. The defect would seem to be a block in electron flow near site I, which can be partially bypassed with succinate. (2) An apparent inability of the reperfused myocardium to extract oxygen did not improve with 2 hours of reperfusion. (3) Epicardial S-T segment mapping suggested that necrosis occurred during reperfusion. (4) There was an altered distribution of tritiated digoxin in the reperfused area. The results show that reperfusion for 2 hours did not improve myocardial viability after 60 minutes or more of ischemia.

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Adenosine TriphosphateAnimalsCoronary CirculationCoronary DiseaseDigoxinDogsElectrocardiographyFemaleHeart Conduction SystemMaleMitochondria, MuscleMyocardial ContractionMyocardiumOxidative PhosphorylationOxygen ConsumptionSwineJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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J J Kane, M L Murphy, J K Bissett, N deSoyza, J E Doherty, K D Straub. 1975. Mitochondrial function, oxygen extraction, epicardial S-T segment changes and tritiated digoxin distribution after reperfusion of ischemic myocardium.. https://doi.org/10.1016/0002-9149(75)90530-5

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