[Platelet-monocyte aggregate formation in patients with coronary heart disease and disorders of carbohydrate metabolism].

Circulating monocyte-platelet aggregates can release procoagulant, oxidative and mitogenic factors, thereby contributing to arterial thrombosis. The aim of our study was the estimation of heterophilic leukocyte-platelet aggregates in patients referred for coronary angiography, dependent on the degree of coronary stenosis and the disturbances of carbohydrate metabolism. Flow-cytometric analysis was performed in 50 consecutive patients with positive exercise test (age 54.2 +/- 6.4 years): 27 with normal glucose tolerance, 7 with impaired glucose tolerance and 16 with type 2 diabetes, and in 16 healthy subjects (age 44.8 +/- 14.1 years). We found that patients with coronary heart disease had increased leukocyte-platelet aggregate formation in comparison to the controls (the percentage of monocyte-platelet aggregates 47.5 +/- 23.0 vs 25.7 +/-12.8, p = 0.003, mean fluorescence intensity (MIF) 187.6 +/- 117.2 vs 79.3 +/- 42.8, p = 0.002, the percentage of granulocyte-platelet aggregates 20.7 +/- 10.4 vs 17.0 +/- 3.6, p = 0.009, MIF 64.2 +/- 41.3 vs 40.9 +/- 6.3, p = 0.008). The highest percentage of heterophilic aggregates was observed in patients with 1- and 2-vessel disease and those with "clean" vessels. In diabetic patients the percentage and MIF of granulocyte-platelet aggregates were decreased in comparison to the subjects with normal glucose tolerance (16.7 +/- 7.2 vs 22.8 +/- 9.8, p = 0.03 and 44.3 +/- 10.8 vs 74.4 +/- 48, p = 0.009, respectively). There was no increase in glycoprotein CD14 expression in any of the group studied. We found a positive correlation between the percentage of monocyte-platelet aggregates and fasting insulin level (r = 0.369, p = 0.04) and a negative correlation between MIF of monocyte-platelet aggregates and HDL level (r = -0.459, p = 0.012), between MIF CD14 and HDL level (r = -0.435, p = 0.02), and between the percentage of granulocyte-platelet aggregates and postprandial glycaemia (r = -0.4117, p = 0.03). We concluded that: 1. the patients with "clean" vessels represent a group of high atherothrombotic risk. 2. the patients with minimal coronary stenosis may benefit from anti-inflammatory and antiplatelet treatment.