Patent foramen ovale (PFO) may be associated with migraine, especially migraine with aura (MA), when the PFO is permanent right-left shunt (RLS), large RLS, and large-size PFO, a recent study found.
Patent foramen ovale (PFO) may be associated with migraine, especially migraine with aura (MA), when the PFO is permanent right-left shunt (RLS), large RLS, and large-size PFO, a recent study published in Medicine found. Still, the potential connection between PFO and migraine requires more research to determine whether the relationship is causal or symbiotic, the authors noted.
The foramen ovale is a hole between the right and left upper chambers of the heart that typically closes immediately after birth. But in approximately 25% of healthy individuals, the hole fails to close and remains as a PFO. It is the most common type of RLS, accounting for about 95% of all cases.
Past research has suggested that the rate of PFO occurrence is significantly higher in migraineurs than in the general population. The new paper aimed to assess the rates of PFO and RLS grades in migraine cases with and without aura to evaluate the relationship between migraine and PFO.
Researchers enrolled 251 patients diagnosed with migraine, then conducted in-person interviews to collect patient information and capture the clinical characteristics of diagnostic criteria for migraine without aura (MO) and MA. Of the overall patient population, 62 cases were classified as MA and 189 cases were classified as MO. Ultrasound technicians then performed contrast transthoracic echocardiography (c-TTE) and contrast transcranial Doppler ultrasonography (c-TCD) to screen for and evaluate the rates of PFO and RLS grades. A control group comprised 275 healthy individuals.
In migraine patients overall, the rates of permanent RLS, total RLS, and large RLS were 11.16%, 39.04%, and 17.13%, respectively. In the control group, the respective rates were 6.18%, 23.64%, and 7.27%—significantly lower than those in the migraine cohort.
The findings also showed that patients with MA had higher rates of permanent RLS, total RLS, and large RLS versus those with MO. Permanent RLS was seen in 20.96% of patients with MA versus 7.93% of those with MO; total RLS was present in 48.38% of patients with MA versus 35.98% in patient with MO; and 27.41% of patients with MA showed large RLS versus 13.76% in the MO cohort.
In the group overall, 25 migraine cases and 14 controls were assessed with transesophageal echocardiography (TEE) to characterize the PFOs by large-size (≥ 2.0 mm), length in mm, and long-tunnel PFO (≥ 10 mm). Although the sample size was small, a much higher percentage of the migraine group showed large-size PFO compared with the control group (36% vs 7.14%).
The authors noted that the study had limitations, including some of the participants were outpatients and the fact that only some patients were assessed with TEE. They also stated that further research will be necessary to determine whether PFO and migraine have a causal or symbiotic relationship.
Zhao Q, Liu R, Zhou J, Dong Z, Chen Y. Prevalence and grade of RLS in migraine. Medicine (Baltimore). Published online January 29, 2021. doi:10.1097/MD.0000000000024175