Reduced Arteriosclerotic Plaque Thrombus Formation

Sixty surgical patients with cerebrovascular accidents and angiographically diagnosed carotid plaques were divided into two groups: .1) pre-treatment with aspirin (650mg/day) and dipyridamol (25mg/tid) (42 patients); 2) no treatments (18 patients). The control group consisted of 10 autopsy of patients dying for unrelated cause.

SEM examination of the endarterectomy plaque revealed intact red blood cells in 12 of 42 pre-treated and 18 of 18 untreated specimens; degenerating red blood cells and cell fragments (24/42, 18/18); fibrin (24/42, 18/18) and white blood cells (15/42, 18/18). These were frequently enmeshed in large surface thrombi. Cholesterol crystals (6 μm) were matted on the plaque surface (12/42, 15/18), and spherical globules averaging 3 to 10 μm sporadically blanketed the surface (6/42, 6/18). Plaque from the asymptomatic controls was smaller and less thrombotic. Energy dispersive analysis x-rays (EDAX) of the inner surface of all 70 specimens (50 years old +) revealed surface calcium deposits and nodules in 18 of the surgical cases (12/42, 6/18), and diffuse calcium deposits in 6 controls.

Treatment with aspirin and dipyridamol significantly reduces plaque thrombosis.