Type IIb von Willebrand disease: role of qualitative defects in atherosclerosis and endothelial dysfunction.

Objective: To verify whether a hereditary bleeding tendency, such as von Willebrand disease (vWD) type IIB, protects against the onset of atherosclerosis.

Methods: Twenty-four patients with vWD type IIB and 24 healthy controls, matched for common atherosclerotic risk factors. All patients were evaluated by color Doppler ultrasound of the common carotid, carotid bifurcation, common femoral artery, brachial artery, and abdominal aorta, investigating intima-media thickness (IMT) and presence of plaques in each arterial district. Flow mediated dilation (FMD) of the brachial artery was used to test endothelial function.

Results: vWD type IIB patients presented no significant difference in IMT in any arterial district. FMD showed no differences between the 2 groups.

Conclusions: The quantitative clotting defect characteristic of vWD type IIB does not seem to protect against atherosclerosis.