[Accentuation of myocardial ischemia during coronary recanalization in the acute phase of myocardial infarction].

Coronary recanalisation during the acute phase of myocardial infarction, especially by in situ infusion of thrombolytic agents, is accompanied in most cases by rapid regression of chest pain and a reduction in the degree of ST elevation. However, a multicentre retrospective study of 104 attempts at recanalisation, including 78 successful procedures, showed in 10 cases (12.8 p. 100), an apparently paradoxical accentuation of the chest pain with or without increased ST elevation, at the time of angiographically demonstrable recanalisation. This phenomenon may be interpreted as being the result of aggravation of the ischaemia of the border zone, the objective of therapy. Several pathogenic hypotheses, all with experimental proof, may be suggested to explain these observations (haemorrhagic infarction, non reperfusion, ischaemic contraction due to massive intracellular flow of calcium, etc.). It is usually associated with arrhythmias and may be considered to be a reliable sign of recanalisation. It may also explain certain cases of persistence of chest pain and ECG changes despite the demonstration of a permeable epicardial artery on initial coronary angiography.