Effects of laser-generated tissue debris on aggregation of human platelets

This study examined the effects of laser-generated tissue debris from thrombus, atheroma, and normal aorta on platelet aggregation. Debris supernatant and suspension from lased thrombus induced dose-related aggregation, maximal at 48 +/- 12% and 65 +/- 2%, respectively. Debris suspension from normal aorta induced maximal aggregation of 35 +/- 12%, but the debris from atheromatous aorta surprisingly had no effect on platelet aggregation. The debris particle count was in the range of 10(10) to 10(12) per liter. Aspirin, 0.2 and 2.0 mmol/L, only weakly inhibited the debris-induced aggregation, and heparin up to 10 U/ml was ineffective. However, iloprost reduced aggregation to 40 +/- 11% of control at 0.3 ng/ml, and totally abolished it at 3 ng/ml. Soluble and particulate laser-generated debris from vascular tissue and thrombus may cause platelet aggregation in vitro. This may have implications for laser coronary angioplasty.