Background and Purpose— Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary arteriopathy, which mainly involves the brain causing stroke and dementia. Mice expressing the mutated protein display early dysfunction in vasoreactivity in resistance arteries, but studies of patients have been inconclusive so far.

Methods— We examined peripheral endothelium-dependent vasodilatation in 10 CADASIL-patients and 20 controls using 3 methods: venous occlusion plethysmography of forearm blood flow with intraarterial acetylcholine and sodium nitroprusside infusions for evaluation of resistance arteries, ultrasound with flow mediated vasodilatation (FMD) of the brachial artery for evaluation of a conduit artery, and the pulse wave method with measurements before and after terbutaline for evaluation of systemic endothelium-dependent vasodilation.

Results— The CADASIL patients displayed reductions in both basal (P=0.034) and stimulated blood flow (P=0.023 for the highest dose of acetylcholine) and an impaired endothelium-dependent vasodilation when investigated in forearm resistance arteries (P=0.019). The FMD and the pulse wave method did not show any reduction in endothelium-dependent vasodilation in the patients.

Conclusions— Endothelium-dependent vasodilation was impaired in resistance arteries, but not in a conduit artery, in the forearm of CADASIL patients.