An animal model of coronary thrombosis and thrombolysis--comparisons of vascular damage and thrombus formation in the coronary and femoral arteries after balloon angioplasty.

The purpose of this study was to compare vascular damage and thrombus formation in the coronary and femoral arteries after balloon angioplasty, and to develop a physiological animal model of intracoronary occlusive thrombus using the balloon angioplasty technique. Angioplasty of the left anterior descending coronary arteries of 14 dogs was performed with an oversized balloon catheter at a high inflation pressure (150 PSI). This was followed angiographically (PTCA protocol). Dogs that showed arterial occlusion were divided into 2 groups. The dogs in 1 group were killed with an overdose of sodium pentobarbital, and those in the other group were infused with a tissue-type plasminogen activator (t-PA; 300,000 unit/kg). Angioplasty of the femoral and profunda femoris arteries (n = 5) was performed in 5 other dogs (PTA protocol). All of the animals were eventually sacrificed and tissue preparations were made from all 3 types of arteries. In the PTCA protocol, acute arterial occlusion was seen angiographically within 2 h in 10 of the 14 dogs. A histological study of the acutely occluded arteries (n = 5) showed thrombotic occlusion and severe arterial damage with medial tearing. T-PA was infused to 5 of the dogs with acute occlusion, and all showed reperfusion. A histological study of these animals showed severe arterial damage, but no macroscopic thrombus. In 4 dogs without acute occlusion, none of the 10 arteries examined were acutely occluded. In the PTA protocol, none of the 10 arteries were acutely occluded. A histological study showed fewer thrombi and less severe arterial damage.(ABSTRACT TRUNCATED AT 250 WORDS)