Angiographic features of the coronary arteries during intracoronary thrombolysis.

The angiographic appearance of the coronary arteries during successful thrombolysis with urokinase was determined in 35 patients with acute myocardial infarction. The lysing process passed through several phases: (a) total coronary occlusion with a convex or irregular distal margin (phase 0); (b) increasing patency of the lumen (phase 1); (c) re-establishment of flow but with intraluminal filling defects and delayed distal flow possibly due to microemboli (phase 2); (d) partial or complete disappearance of the filling defects (phase 3); and (e) further widening of the lumen which eventually attains a smooth regular outline (phase 4). The angiographic features which indicate the presence of coronary thrombosis are occlusion with an irregular or scalloped margin, staining with contrast medium, and progressive patency of the occluded vessel showing intraluminal filling defects.