Selective intracoronary thrombolysis in acute myocardial infarction and unstable angina pectoris.

Streptokinase was infused into the ischemia-related coronary artery at a rate of 1000–2000 U/min for 15–95 minutes in 29 patients with acute myocardial infarction(AMI group) and in five patients with unstable angina pectoris (UAP group). Reopening of the completely obstructed vessel or increase of diameter at the site of subtotal lesions occurred in 22 AMI patients within 15–90 minutes of streptokinase infusion. In four of these patients, antegrade flow to the distal segments of the infarct vessel was seen after intracoronary nitroglycerin or sublingual nifedipine administration, which preceded streptoklinase infusion, and in two patients, streptokinase infusion was combined with recanalization by means of a guide wire. Chest pain was alleviated after reperfusion; ejection fraction was 50.5 ± 12% before and 54.6 ± 9% immediately after successful intracoronary lysis (p < 0.05). Repeat angiography, performed 25 ± 11 days after the acute intervention in 19 AMI patients, revealed reocclusion of the infarct vessel in one patient. Aortocoronary bypass surgery was performed electively in six AMI patients at varying intervals after successful lysis. Upon intraoperative inspection, the bulk of myocardium perfused by the recanalized vessel was found to be viable. Intracoronary streptokinase infusion did not result in opening the complete obstruction or improvement of lumen at the site of subtotal lesions in seven AMI patients and in all UAP patients. The total dose of 128,000 ± 36,000 U of streptokinase resulted in only minor decrease of fibrinogen, from 451 ± 93 mg% to 430 ± 91 mg%. Bleeding from the arterial puncture site in two patients, the only complications that could be attributed to the procedure, was due to heparinization. Intracoronary streptokinase application appears to be a safe and efficient method of achieving reperfusion and alleviating ischemia in the majority of patients with acute myocardial infarction. The method was not beneficial in treating unstable angina pectoris, and its potential for salvage of myocardium is yet to be assessed.