Benefits of late coronary artery reperfusion on infarct expansion progressively diminish over time: Relation to viable islets of myocytes within the scar

doi:10.1016/S0002-8703(96)90522-0

American Heart Journal

Volume 131, Issue 3, March 1996, Pages 451-457

https://doi.org/10.1016/S0002-8703(96)90522-0 Get rights and content

Abstract

To define the time limit and mechanism of the effects of late coronary artery reperfusion on infarct expansion, rats were randomized into one of four groups: permanent left coronary artery occlusion; and 2, 8, and 16 hours of left coronary artery occlusion followed by reperfusion. Two weeks after coronary occlusion, morphometric and histologic analyses were performed. Benefits of late reperfusion on infarct expansion progressively diminished after increasingly long periods of coronary occlusion and were minimal but present after 16 hours of coronary occlusion. The extent of the benefits of late reperfusion on infarct expansion were related to preservation and hypertrophy of small islets of still viable myocytes located mainly in the subepicardium of the scar.

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On a passé en revue les publications comparant l’intervention de revascularisation rapide par rapport à l’intervention tardive chez des patients stables après un IAM.
On n’a trouvé aucun essai prospectif aléatoire, mais plusieurs études rétrospectives. La plupart des séries portant sur l’IAM à onde Q indiquaient une mortalité plus élevée dans les premières phases suivant l’IAM, laquelle diminuait progressivement avec le temps après l’IAM. Lorsque les études évaluaient les IAM incomplets séparément, la différence de mortalité après une revascularisation rapide et une revascularisation tardive semblait moins grande. On remarquait une importante disparité entre les définitions de chirurgie rapide après un IAM dans les études, certaines ayant lieu dès six heures après l’IAM et d’autres, jusqu’à huit jours plus tard. Les facteurs qui accroissaient la mortalité étaient une fonction ventriculaire gauche anormale et l’urgence de l’opération, et certaines études ont trouvé les modèles de risque utiles pour définir un risque accru après l’infarctus. L’accroissement possible du risque d’une opération rapide peut être soupesé d’après le potentiel de meilleur remodelage, de meilleure qualité de vie et de diminution des frais d’hospitalisation.
Des essais prospectifs aléatoires sont nécessaires pour examiner le moment idéal du pontage aortocoronarien chez les patients stables après un IAM.
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Clinical investigationBenefits of late coronary artery reperfusion on infarct expansion progressively diminish over time: Relation to viable islets of myocytes within the scar

Abstract

Am J Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

J Am Coll Cardiol

Am Heart J

J Am Coll Cardiol

Prog Cardiovasc Dis

Am Heart J

Am J Cardiol

The path to myocardial salvage by thrombolytic therapy

Circulation

Long-term effects of intravenous thrombolysis in acute myocardial infarction: final report of GISSI study

Lancet

The wavefront phenomenon of ischemic cell death: 1. Myocardial infarct size versus duration of coronary occlusion in dogs

Circulation

Randomized trial of intravenous streptokinase, oral aspirin, both, or neither among 17,187 cases of suspected acute myocardial infarction

Lancet

Limitation of myocardial infarct expansion by reperfusion independent of myocardial salvage

Circulation

Potential benefits of late reperfusion of infarcted myocardium

Experimental myocardial infarction in the rat: qualitative and quantitative changes during pathologic evaluation

Am J Pathol

Clinical investigation
Benefits of late coronary artery reperfusion on infarct expansion progressively diminish over time: Relation to viable islets of myocytes within the scar