[Should inferior myocardial infarction be thrombolysed?]

Recent randomised studies have demonstrated the benefits of administration of intravenous thrombolytic agents in the acute phase of myocardial infarction. Though the benefits are generally acknowledged in cases of anterior wall necrosis, the results in inferior infarction have been discordant. The early patency rate at 90 minutes after thrombolysis is lower in the right coronary and left circumflex than in the left anterior descending artery. The secondary reocclusion rate is twice as high on the right coronary artery. The significant increase in ejection fraction after thrombolysis has only been demonstrated in 2 of the 8 studies in the literature. The benefits in terms of early mortality were not significant in the GISSI study. A significant decrease in early mortality (7.2% vs 8.8%) was observed only in the ISIS 2 study with streptokinase. The reinfarction rate at 1 year was twice as high when the initial infarct was on the inferior wall. Analysis of the results in the literature shows that the benefits of intravenous thrombolysis was clearcut in certain subgroups of inferior infarction: ST elevation in over 3 leads, mirror-image anterior lead changes, very early treatment (before the 3rd hour), complicated infarcts (atrioventricular block, right ventricular extension, hypotension) or in inferior infarcts occurring after previous anterior infarction.