In general practice, triptan overuse does not increase the risk of ischemic complications. Overuse of ergotamine may increase the risk of these complications, especially in those simultaneously using cardiovascular drugs.

Objective.-To investigate the presence of thromboembolic risk factors and the effect of low-dose acenocoumarol therapy on migraine in patients who spontaneously reported a reduction of their migraine attacks during previous therapeutic use of anticoagulants.Background.-The positive effect of anticoagulants on migraine has been described in case reports and observational studies. It remains unclear whether this concerns only a select group of migraineurs with certain common characteristics.Methods. Results.-All patients had one or more thromboembolic risk factors. Two patients, both with factor V Leiden heterozygosity, experienced a clear improvement of migraine during low-dose acenocoumarol therapy.Conclusions.-Our findings support the hypothesis that migraine, as a phenotype, has different underlying mechanisms, amongst which a thromboembolic tendency. In this group of patients, oral anticoagulants may be a suitable form of migraine prophylaxis, but this needs further clinical investigation. Key words: migraine, migraine prophylaxis, anticoagulants, acenocoumarol, thromboembolic predisposition, hemostasisAbbreviations: INR international normalization ratio (Headache 2004;44:399-402) During the last decade, attention has been given to the increased risk for ischemic events in patients with migraine. Crassard et al reviewed the contribution of hemostasis to the ischemic risk in patients with migraine, particularly with regard to platelet hyperaggregability, antiphospholipid antibodies, and

Several studies have shown that the prevalence of a cardial right-to-left shunt (RLS) in patients with migraine with aura is significantly higher than in patients without migraine. To assess the strength of the possible relationship between RLS and migraine, the literature concerning this subject was systematically reviewed. We identified seven relevant studies. Among patients with RLS migraine with aura was 3.5 times more prevalent than among subjects without RLS [Mantel-Haenszel odds ratio (ORMH) 3.5; 95% confidence interval (CI) 2.1, 5.8]. In patients with ischaemic stroke migraine was more than two times more prevalent in patients with RLS than in patients without RLS (ORMH 2.1; 95% CI 1.6, 2.9). Our review shows that there is a clear association between RLS and migraine, especially migraine with aura. The relationship between RLS and migraine is further substantiated by the observations of disappearance and improvement of migraine symptoms after closure of the foramen ovale. However, the mechanism as well as the question about causality of this association has to be further elucidated.

Treatment patterns in migraine patients with cardiovascular risk factors are largely unknown. A retrospective observational study was conducted to characterize the baseline cardiovascular risk profile of new users of specific abortive migraine drugs, and to investigate treatment choices and patterns in patients with and without a known cardiovascular risk profile. New users of a triptan, ergotamine or Migrafin (n = 36,839) from 1 January 1990 to 31 December 2006 were included. Approximately 90% of all new users did not have a clinically recognized cardiovascular risk profile. The percentage of new users with a cardiovascular risk profile did not differ between new users of a triptan, ergotamine or Migrafin and also did not change during the study period of 17 years. Differences in treatment choices and patterns between migraine patients with and without a known cardiovascular risk profile reveal a certain reticence in prescribing vasoconstrictive antimigraine drugs to patients at cardiovascular risk.