In vivo platelet activity and lipoprotein patterns in coronary artery disease.

In order to determine the effect of hyperlipoproteinemia on the in vivo formation of circulating platelet aggregates (CPA) in patients with coronary artery disease, CPA ratios, lipoprotein pattern, serum cholesterol and triglycerides were determinated in 80 male patients with stable coronary artery disease and hyperlipoproteinemia. Similar studies were performed in 30 male age-matched patients with stable coronary artery disease without hyperlipoproteinemia and 60 male age-matched healthy volunteers; the latter group served as controls. CPA ratios were significantly lowered; i.e. an increase was observed in circulating platelet aggregates in 24 patients without hyperlipoproteinemia as compared with the values in the control group. All the cardiac patients with hyperlipoproteinemia had a significantly lower CPA ratio than the patients without hyperlipoproteinemia. Moreover, the lowering in CPA ratio was more marked among patients with type II a hyperlipoproteinemia than in those with type IV. We think that this in vivo test for platelet function may throw more light on the effect of hyperlipoproteinemia on the in vivo aggregation of circulating platelets in patients with coronary artery disease.