[Intracoronary application of streptokinase in acute myocardial infarction and non-stable angina pectoris (author's transl)].

Streptokinase, 1000-2000 U/h, was administered into the coronary artery via catheter over 15-60 minutes to 12 patients. Six of them had an infarct in the early stage (A), two a fresh re-infarction (B) and four nonstable angina (C). Nitroglycerine had been injected at a dose of 0.1-0.45 mg into the coronary artery before infusion of streptokinase. Nitroglycerine induced angiographic demonstrably better filling of the infarcted vessel in two patients of group A. After intracoronary injection of streptokinase the occluded artery re-opened or, if there had been subtotal stenosis, significantly widened in all patients of group A. But there was no complete disappearance of the narrowing. In the patients of group B and C there was no angiographic evidence of change, neither after nitroglycerine nor after streptokinase. There was no marked change in systemic clotting function. The findings indicate that after acute, first-time infarction a fresh coronary thrombus forms on the basis of atheromatous narrowing. The thrombus can be quickly removed by selective lysis via coronary catheter. Fresh thrombotic deposition is less likely on re-infarction or in nonstable angina. These results must be confirmed by observation on a larger group of patients.