Intracoronary thrombolysis in syndromes of unstable ischemia: angiographic and clinical results.

For an assessment of association of intracoronary thrombus with prolonged unstable myocardial ischemia and of the possible efficacy of local thrombolysis, 12 patients with recent prolonged unstable angina underwent 13 intracoronary streptokinase infusions. All patients had prolonged rest angina within 5 days of coronary angiography. Abnormal resting ECGs were present in all patients, and 10 had ECG changes referable to the ischemic-related vessel. There were seven native coronary and six bypass graft infusions with a mean streptokinase dose of 187,00 +/- 22,000 IU (standard error of mean). Angiographic findings consistent with intracoronary thrombus were identified in 11 of 13 ischemia-related vessels. Evidence of partial or complete intracoronary thrombolysis was noted angiographically in 10 of 13 ischemia-related vessels (77%), although reestablishment of anterograde flow was seen in only two of six totally or subtotally occluded vessels. Nine patients experienced rest angina during the 48 hours prior to infusion, whereas only three experienced angina during the 48 hours following infusion. In conclusion, angiographic findings before and after thrombolysis in this preliminary study demonstrate a high frequency of intracoronary thrombus in preinfarction syndromes. Furthermore, these limited observations suggest a decrease in angina frequency following thrombolytic therapy.