Coronary artery deposition of factor VIII-related antigen in ischemic heart disease

von Willebrand factor and soluble E-selectin in the prediction of cardiovascular disease progression in hyperlipidaemia

Two specific endothelial cell products, von Willebrand factor and soluble E-selectin, were measured together with serum lipids, lipoprotein(a), systolic and diastolic blood pressure (SHP, DBP) in a follow up study of 162 patients attending a dedicated lipid clinic. Patients were further classified by the presence or absence of symptomatic vascular disease and smoking. After a mean of 49 months, 45 patients experienced a cardiovascular event (fatal or nonfatal myocardial infarction, stroke, or arterial surgery) and 11 developed non-cardiovascular diseases, including cancer. In univariate analysis, existing vascular disease (P < 0.01), increased levels of von Willebrand factor (P < 0.0001) and low density lipoprotein cholesterol (P < 0.02), greater age (P < 0.01), and lower levels of soluble E-selectin (P < 0.03) were all predictive of future vascular events. However, in multivariate analysis, only increased von Willebrand factor was predictive (P < 0.001). von Willebrand factor was also higher in patients who developed non-cardiovascular disease relative to those free of disease (P < 0.05). Our data support the hypothesis that increased levels of von Willebrand factor are an indicator of poor prognosis in patients with atherosclerosis or its risk factors.

Circadian variation of tissue plasminogen activator and its inhibitor, von Willebrand factor antigen, and prostacyclin stimulating factor in men with ischaemic heart disease

OBJECTIVES

To determine whether plasma concentrations of tissue plasminogen activator antigen, von Willebrand factor antigen, and prostacyclin stimulating factor and plasminogen activator inhibitor activity show circadian variation in men with ischaemic heart disease.

DESIGN

Blood samples were obtained every four hours for 24 hours from 10 men with ischaemic heart disease. The men were ambulant from 08:10 until 00:00 when they went to bed and they remained in bed until 08:00 the following morning.

PATIENTS

Ten men with positive diagnostic exercise tolerance tests with no significant past history, who were not regularly taking any medical treatment except for glyceryl trinitrate.

RESULTS

There was significant circadian variation in plasminogen activator inhibitor activity (p = 0.001) (peak value 04:00 and trough value 20:00), but not in plasma concentrations of tissue plasminogen activator antigen, von Willebrand factor, or prostacyclin stimulating factor.

CONCLUSION

Men with ischaemic heart disease showed a significant circadian variation in fibrinolysis. The combination of peak values of plasminogen activator inhibitor activity and failure of plasma concentrations of tissue plasminogen activator antigen to increase in the early morning must predispose to thrombosis at this time. The circadian variation in fibrinolysis may contribute to the increased incidence of myocardial infarction in the morning.

Immunocytochemical features of obstructed saphenous vein coronary artery bypass grafts

The peroxidase-immunoperoxidase immunocytochemical method was used on 27 saphenous vein coronary artery bypass grafts, which had been resected because of recurrent angina, to identify in situ cellular and humoral elements possibly associated with graft occlusion. Immunostaining was performed on paraffin wax embedded control saphenous vein and graft sections incubated directly with primary antibodies against von Willebrand antigen (vWFAg), fibronectin, fibrinogen, leucocyte common antigen (LCA), lysozyme, vimentin, desmin, platelet factor 4, and thrombospondin. Antigens were visualised by a chromogen providing an orange-red immunoprecipitate at the site of epitope localisation. The intraluminal, amorphous exudate present in most grafts was not composed simply of fibrin or fibrinogen, as previously thought, but was a multiprotein complex including wWFAg, fibronectin, thrombospondin and platelet factor 4. Along with macrophages, these components probably enter the graft after haemodynamic, physical, and chemical injury to, and disruption of, the endothelial cell. Progressive myointimal proliferation and fibrosis of these grafts may be local repetitive responses to macrophages and platelets, cells previously known to participate in vascular disease.