Vascular Dysfunction in Stroke and CADASIL

Sammanfattning: Cerebrovascular disease (CVD) is strongly linked to hypertension and generally occurs later in life than coronary artery disease (CAD). Three quarters of the patients with symptomatic CVD are above 65 years of age. The risk factors are the same for CVD and CAD, but the relative importance of the vascular risk factors differs greatly.Genetic causes of stroke are relatively rare. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL) is a hereditary disease which causes CVD in young adults and middle-aged people, with migraine, stroke, psychiatric illness and dementia as clinical manifestations.The subject of this thesis is vascular function in stroke and CADASIL. Endothelium-dependent vasodilation (EDV) and arterial stiffness were investigated by different methods in stroke patients and CADASIL patients compared with healthy controls. Venous occlusion plethysmography with intra-arterial acetylcholine was used to evaluate EDV in the forearm resistance vessels. Flow-mediated vasodilation of the brachial artery was used to evaluate EDV in a conduit artery. Stroke patients displayed reduced EDV in resistance vessels compared with a healthy control group, but this reduction was not significant when, in a larger group of stroke patients, adjustments were made for blood pressure, antihypertensive treatment and other risk factors. Flow mediated vasodilation of the brachial artery was reduced in the stroke patients even after adjustment for risk factors. Compared with controls, the CADASIL patients showed similar EDV in the conduit artery, but reduced EDV in resistance vessels.Arterial compliance was evaluated by augmentation index from pulse wave analysis, by a ratio of cardiac stroke volume and pulse pressure, and by the distensibility of the carotid artery in relation to pulse pressure. Stroke patients and CADASIL patients did not display any significant increase in arterial stiffness when evaluated by these methods.