Page 78 - Migraine, the heart and the brain

Chapter 4
Manhattan study (NOMAS) was questioned about migraine and – as part of extensive cardiovascular evaluation – transthoracic echocardiography (TTE) was performed [16]. In this study evaluating 288 persons, the reported prevalence of PFO was similar in migraine with aura patients (16%), without aura (11%) and controls (15%). It was striking that as many as 79% of migraineurs were diagnosed with migraine with aura, whereas generally migraine with aura only makes up maximally 30% of migraineurs [17]. A great number of the migraine with aura patients perhaps were misdiagnosed and probably were migraine without aura patients in which the prevalence of RLS is known to be comparable with controls. Garg et al. [18] also found no differences in PFO prevalence among migraine with aura patients (27%), migraine without aura (26%) and age-matched and sex-matched controls (26%). The study used both TTE and TCD-c in 288 persons recruited from a headache center. Due to a very short evaluation time, pulmonary RLSs and small PFOs could have been missed. Finally, preliminary data from a large population-based Dutch study using TCD-c presented recently at a conference seems to con rm the increased prevalence of RLS among migraine with aura patients, and its publication is eagerly awaited.
A PAVM allows right-to-left shunting at the pulmonary level. Post et al. [19] studied 196 consecutive persons referred for screening of hereditary hemorrhagic telangiectasia (HHT) and showed that migraine with aura was present in 24% of these patients with a PAVM and only in 6% in patients without PAVM (P = 0.001). The prevalence of migraine without aura was not increased in individuals with a PAVM. A limitation of this study was that the migraine diagnosis was made only by reviewing returned questionnaires. Marziniak et al. [20] investigated 106 HHT patients and also showed that prevalence of migraine with aura in patients with PAVM (39%) was higher than that in patients without PAVM (10%); numbers of HHT patients with migraine with aura, however, were small (n = 18).
Only recently it was shown that, similar to PFO, the occurrence of PAVM is also relatively common in the general population. Woods et al. [12] described 104 healthy individuals (63% women) who were recruited to undergo TTE for RLS screening: 71% were found to have a RLS (38% had a PFO, 28% had a PAVM, 5% had evidence of both). In this study, any appearance of left-sided heart microcavitations was considered positive for a RLS, which is the lowest threshold possible and explains this very high prevalence of RLS. Before TTE, a 15-question migraine questionnaire was completed by participants, which was graded by a neurologist blinded for TTE results. Migraine with aura was diagnosed in 12% and migraine without aura in 29%. The prevalence of RLS in migraine with aura was 67%, which was not higher than that in migraine
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