[Advances in intracoronary thrombolysis treatment]

Based on the results of intracoronary thrombolysis in 30 patients with initial onset of anterior myocardial infarction, we concluded that: (1) left ventricular function and clinical features are markedly improved when reperfusion is accomplished within four hours after coronary artery occlusion; and (2) intracoronary thrombolysis therapy should be considered possible up to 10 hours after the onset of myocardial infarction to prevent expansion of infarct sizes and to preserve ventricular functions. Not infrequently, there is a significant stenosis at the site of initial occlusion after thrombolytic therapy, which results in an immediate reocclusion. Consequently, percutaneous transluminal coronary angioplasty (PTCA) is now widely performed after thrombolytic treatment to achieve more definite revascularization. Our early experiences showed that PTCA following thrombolytic treatment has an increased potential for reinfarction rather than added benefits for left ventricular functions. More recently, however, since our PTCA technique has been improved so as to achieve sufficient dilatation of the stenosed coronary artery, there has been less tendency to immediate reinfarction after the procedure for acute myocardial infarction. Whether PTCA should be added to thrombolytic therapy during the acute phase of myocardial infarction is controversial. The alternative is to wait until it can be performed on an elective basis. It is obvious that early revascularization is essential for preserving left ventricular functions after acute myocardial infarction. For this reason, thrombolytic agents such as tissue plasminogen activator and plasminogen proactivator, which can be administered intravenously, are being intensively sought using molecular biological techniques. The ideal thrombolytic agents should have more fibrin-specific properties with longer half-lives than currently-available substances. However, so far none of these novel agents, have been studied in patients.