Cerebrovascular reactivity to l-arginine in the anterior and posterior cerebral circulation in migraine patients.

OBJECTIVE - Cerebral infarction preferentially affects the posterior cerebral artery distribution in migraine patients. The results obtained from the few known studies that have compared the anterior and posterior cerebral endothelial function are contradictory. To the best of our knowledge, cerebrovascular reactivity to L-arginine (CVR), measured by transcranial Doppler sonography (TCD), has not been previously used to determine the posterior cerebral endothelial function in migraine patients with (MwA) and without aura (MwoA). MATERIALS AND METHODS -  Forty migraine patients without comorbidities (20 MwA, 20 MwoA) and 20 healthy subjects were included. By employing strict inclusion criteria, we avoided the possible vascular risk factors. Mean arterial velocity in the middle cerebral artery (MCA) and the posterior cerebral artery (PCA) was measured by TCD before and after infusion of L-arginine, and CVR to L-arginine was then calculated. RESULTS - All migraine patients had lower CVR to L-arginine in PCA (P = 0.002) and similar in MCA (P = 0.29) compared to healthy subjects. This difference was also present in MwA and MwoA compared to healthy subjects (P = 0.003). CONCLUSIONS -  Lower CVR to L-arginine in PCA in migraine patients could associate migraine and cerebral infarcts that are more common in the posterior cerebral artery distribution.