Biochemical Evaluation of Standard Treatment With Streptokinase in Acute Myocardial Infarction

The biochemical effect of standard dosage of streptokinase (SK) in acute myocardial infarction (AMI) suggested to be less than 24 hours old has been evaluated. The trial was carried out in a medical department of a city hospital having no coronary unit. The SK dose was: a loading dose of 0.25 times 106 units, followed by 0.1 × 106/hour for 20 hours. Phenindione was given from the very beginning in the SK group (67 pats.) and in the control group (68 pats.). Special protocols were used. All therapy of any complication was standardized. The biochemical effect was evaluated by measuring the euglobulin clot lysis time (ELT), plasma thrombin time, fibrinogen, plasminogen, fibrinogen‐fibrin breakdown products, α‐2 macroglobulin, and α‐1 antitrypsin, and the clinical effect by close ECG. recordings and estimations of SGOT, LDH and CPK. A persistent significant fibrinolytic effect was obtained in at least 85% of the patients for 20–24 hours. Plasminogen depletion was seen in around 15%, generally lasting 1–2 days. Fibrinogen‐fibrin breakdown products developed during the SK treatment. Increased amounts were seen in a few other patients with thromboembolic complications or malignancy. Normal values were found in incomplicated cases. The lethality was identical in the two groups, which were clinically comparable but not randomized. The frequency of bleeding complications was identical, but fewer thromboembolic cases were seen in the SK group, as illustrated by autopsy. The study showed that a standard treatment can be performed without difficulties or serious complications, producing significant fibrinolytic activity in around 80–90% of the patients. The final evaluation of the possible effect of fibrinolytic therapy in AMI should be carried out in coronary units. Many well randomized patients are necessary.