Page 94 - Migraine, the heart and the brain

Chapter 5
atherosclerotic lesions (20). MFS is caused by mutations in the gene encoding for the extracellular matrix protein brillin-1. Contrary to diseases with vascular dilatation, recently it was found that the aortic rigidity measured by aortic pulse wave velocity in migraine is increased (21), whereas it has also been shown that compliance of brachial and femoral artery were decreased in migraineurs compared with controls (22).
A possible effect of these abnormalities found in the systemic blood vessels is a reaction from the endothelial cells, which secrete vasoactive mediators like vasodilator nitric oxide and vasoconstrictor endothelin-1. Several studies have found increased levels of these mediators to be present in migraineurs. These mediators are in turn thought to be able to produce cortical spreading depression. Another possibility is the presence of micro-emboli in the affected aortic root, which can act as a trigger for cortical spreading depression and was recently shown by Nozari et al. in mice (23). The use of speci c vasoactive drugs in MFS patients with a dilating aortic root should also be considered, but was not investigated in this study. However most commonly used medications in MFS probably have a prophylactic rather than a migraine enhancing effect.
In our subjects the AR operation itself was not associated with the presence of migraine, as in all but one subject, migraine started many years before the operation. Surgical repair of the dilated aortic root/ ascending aorta for MFS patients to prevent a dissection, is usually performed at a threshold of an external aortic diameter of 50 mm (24). It is feasible to think that thus the dilatation would be associated with the increased migraine prevalence, however in MFS patients without AR but with dilatation not yet requiring operation no increased prevalence of migraine with aura was found. Possibly this non-operated MFS group is more benign and displays a different vascular phenotype.
Previously, one of us hypothesised that the dural ectasias frequently found in MFS could be an explanation for the increased headache prevalence (10). However, in the 42 patients in whom results of spinal imaging were known, we failed to nd an association between migraine with aura and dural ectasias.
strengths and limitations
As Marfan prevalence is low, numbers of migraineurs in the study are small, especially after gender strati cation. The use of a telephone semi-structured interview aids diagnostic accuracy, whereas the study by Vis et al. (11) investigating partly the same
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