The Multicenter Study Of The Relationship Between Right-to-left Shunt And Migraine

The first part: Right-to-left shunt detected using contrast-enhanced transcranial Doppler: A comparison of provocation manoeuvres between cough and a modified Valsalva manoeuvreObjective: To compare the two ways of provocation maneuver(cough and modified Valsalva maneuver)in detecting right to left shunt(RLS)by contrast-enhanced transcranial Doppler(c-TCD).Methods: For each participant,c-TCD was performed for three different ways:(i)at rest state(RS),(ii)at cough and(iii)at modified Valsalva maneuver(m-VM)which blew into a tube connected with a sphygmomanometer at 40 mm Hg for 10 s.The severity of RLS were assessed with a five level grade according to the number of microbubbles(MBs): Grade 0=Negative;Grade?=1-10 MBs;Grade?=11-25 MBs;Grade?>25 MBs,and no curtain;Grade?=curtain.Results: The positive rate RLS of were 56.2%,82.1% and 89.5% for RS,cough and m-VM,respectively(p<0.001).The positive rate of RLS detected at VM was higher than at cough by c-TCD(P=0.017)and there was a significant difference between cough and VM in terms of the severity of RLS(p<0.005).Conclusion: m-VM is a relatively effective provocation maneuver rather than cough maneuver in RLS detection by c-TCD.The m-VM should be used as an effective provocation maneuver in clinical practice.The second part: Prevalence and extent of right-to-left shunt on contrast-enhanced transcranial Doppler in Chinese patients with migraine in a multicenter case-control studyObjective: The association between right-to-left shunt(RLS)and migraine is still debated.The aim of this study is to investigate the prevalence and grade of RLS in Chinese patients with migraine and to evaluate the relationship between RLS and migraine.Methods: A multi-center case-control study of contrast-enhanced transcranial Doppler was conducted in 931 consecutive patients with migraine(240 of 931 were migraine with aura and 691 of 931 were migraine without aura group)and 282 healthy adults.Clinical trial no.NCT02425696.Results: The prevalence of RLS was 46.1%,63.8% and 39.9% in the migraine group,migraine with aura group(MA+)and migraine without aura group(MA-),respectively,significantly higher than that of healthy group(29.4%,p <0.001;p <0.001;p <0.001).The positive rate of large RLS in the migraine group,MA+ group and MA-group was 20.6%,32.1% and 16.5%,respectively,significantly higher than healthy group(6.4%,p <0.001;p <0.001;p <0.001).There was no difference among groups in terms of positive rate of permanent RLS(p =0.704).Conclusion: This multi-centre case-control study suggested that there is an association between RLS and migraine with and without aura,especially when the shunt is large.