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PubMed · 803058

Subendocardial S-T segment changes during acute coronary occlusion.

R A Guyton
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Abstract

Subendocardial ischemia during coronary occlusion in dogs was studied using S-T segment elevations in unipolar subendocardial electrodes. Alterations in heart rate or cardiac output caused quantitatively similar changes in subendocardial and epicardial S-T elevation. Increasing blood pressure from 75 to 100 or 75 to 125 mm Hg caused a smaller reduction in subendocardial than in epicardial S-T elevation (p less than 0.01). In this situation, therefore, subendocardial ischemia tends to be maintained while epicardial ischemia is reduced by higher arterial pressures. Hemodynamic manipulations can cause quantitatively different changes in subendocardial and epicardial S-T segment elevation.

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AnimalsDogsElectrocardiographyEndocardiumHeart Arrest, InducedHeart Conduction SystemIntraoperative ComplicationsMyocardial InfarctionMyocardiumOxygen ConsumptionJournal Article

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BibTeXRIS

R A Guyton. 1975. Subendocardial S-T segment changes during acute coronary occlusion.. https://doi.org/10.1016/s0003-4975(10)63852-0

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