Page 59 - Migraine, the heart and the brain

introduCtion
epidemiologic and animal studies have suggested a complex relation between
migraine, ischemic brain lesions, and systemic right-to-left shunts (RLS).1–6
Participants with migraine had higher prevalence of subclinical deep white matter hyperintensities and brain infarcts,2,3,5 migraine with aura was associated with
increased prevalence of ischemic stroke 1,7 and RLS,4,6 and RLS were more prevalent 3 in patients with cryptogenic stroke.8,9 In uncontrolled and open-label studies,10–12
but not in a sham-controlled study,13 closing patent foramen ovale reduced migraine attack frequency and risk of stroke recurrence.14,15
In mice, carotid injection of small experimental emboli induced cortical spreading depression (CSD),16,17 the electrophysiologic correlate of migraine aura and a putative trigger for migraine attacks.18 Altogether, microemboli through RLS might cause cerebral ischemia and might trigger attacks of migraine with aura. Thus while in most migraineurs attacks cease, recurring spontaneously at older age,19 in migraineurs with RLS, attacks might continue recurring. Most of these data, however, were obtained in patients from headache clinics who likely were more severely affected than the average migraineur. It thus is uncertain whether and to what extent these conclusions can be extrapolated to the migraineur at large.
In the present study, we assessed whether RLS are (1) more prevalent in migraineurs from the general population, (2) associated with a higher prevalence of ischemic brain lesions on MRI, and (3) associated with ongoing migraine activity. To this end, we assessed and correlated (1) presence, type, and size of RLS; (2) presence and type of ischemic brain lesions; and (3) migraine activity, de ned as number of attacks in the preceding year in a cohort of unselected but well- de ned migraineurs (n = 203) and controls (n = 83) from the general population- based Cerebral Abnormalities in Migraine: An Epidemiological Risk Analysis Study Part 2 (CAMERA-2).3 As CAMERA-2 is a 9-year follow-up of the CAMERA-1 study,2 in which all migraineurs were initially diagnosed and characterized, we could reliably analyze both still active migraineurs in whom attacks were still recurring and inactive migraineurs in whom attacks had meanwhile ceased recurring.
Right-to-left shunts and migraine
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