fibrinopeptide-b and Coronary-Disease

Basal plasmin and thrombin activity in plasma were assessed by radioimmunoassay of the fibrinogen derivatives containing the sequence B beta 15-42 and of fibrinopeptide A respectively in a cross sectional controlled study of men with coronary artery disease. Compared with healthy controls (n = 33) men with angiographically defined coronary artery disease (n = 98) had a modest but significant increase in concentrations of fibrinopeptide A, indicating an activated coagulation system. Concentrations of B beta 15-42 were similar in those with coronary artery disease and in the controls. The enhanced thrombin activity in coronary artery disease is in keeping with current evidence suggesting an association between coronary artery disease and a hypercoagulable state.

Topics: Adult; Coronary Disease; Coronary Vessels; Cross-Sectional Studies; Fibrin Fibrinogen Degradation Products; Fibrinolysin; Fibrinopeptide A; Fibrinopeptide B; Humans; Male; Middle Aged; Peptide Fragments; Scotland; Thrombin

The hypothesis that exercise-induced myocardial ischemia is associated with abnormal platelet activation and fibrin formation or dissolution was tested in patients with coronary artery disease undergoing upright bicycle stress testing. In vivo platelet activation was assessed by radioimmunoassay of platelet factor 4, beta-thrombo-globulin and thromboxane B2. In vivo fibrin formation was assessed by radioimmunoassay of fibrinopeptide A, and fibrinolysis was assessed by radioimmunoassay of thrombin-increasable fibrinopeptide B which reflects plasmin cleavage of fibrin I. Peripheral venous concentrations of these substances were measured in 10 normal subjects and 13 patients with coronary artery disease at rest and during symptom-limited peak exercise. Platelet factor 4, beta-thromboglobulin and thromboxane B2 concentrations were correlated with rest and exercise catecholamine concentrations to determine if exercise-induced elevation of norepinephrine and epinephrine enhances platelet activation. Left ventricular end-diastolic and end-systolic volumes, ejection fraction and segmental wall motion were measured at rest and during peak exercise by first pass radionuclide angiography. All patients with coronary artery disease had documented exercise-induced myocardial ischemia manifested by angina pectoris, ischemic electrocardiographic changes, left ventricular segmental dyssynergy and a reduction in ejection fraction. Rest and peak exercise plasma concentrations were not significantly different for platelet factor 4, beta-thromboglobulin, thromboxane B2, fibrinopeptide A and thrombin-increasable fibrinopeptide B. Peripheral venous concentrations of norepinephrine and epinephrine increased significantly (p less than 0.001) in both groups of patients. The elevated catecholamine levels did not lead to detectable platelet activation. This study demonstrates that enhanced platelet activation, thromboxane release and fibrin formation or dissolution are not detectable in peripheral venous blood of patients with coronary disease during exercise-induced myocardial ischemia.

Topics: Adult; Aged; Blood Platelets; Blood Proteins; Catecholamines; Coronary Disease; Exercise Test; Fibrin; Fibrinopeptide A; Fibrinopeptide B; Humans; Male; Middle Aged; Physical Exertion; Renin; Thromboxane B2