Platelet adhesion in hyperlipidemic and hypertensive patients.

Platelet adhesion was studied in whole blood using a simple stagnation flow method in patients at high risk for the development of atherosclerosis. Fourteen patients with hypercholesterolemia, 26 with hypertriglyceridemia and 25 normolipidemic hypertensive subjects were compared with 75 normal (normotensive and normolipidemic) subjects. Increased platelet adhesion was found in hypercholesterolemic (but not hypertriglyceridemic) patients only when native blood with no anticoagulants was used. In hypertensive patients, platelet adhesion was significantly elevated, but remarkably reduced by beta-blocker drugs. Propranolol and atenolol significantly reduced platelet adhesion, but this effect was found to take a longer time than that required for significant blood pressure reduction.