Patent Foramen Ovale

Patent Foramen Ovale and Migraine

Patent foramen ovale is a form of heart defect—sometimes called a "hole in the heart." The foramen ovale permits fetal circulation to bypass the lungs in yet-to-be-born babies, and closes at the time of birth to permit blood flow to the lungs. Occasionally, the foramen ovale does not close all the way after birth, and is thus patent, or open. The size of the opening varies in a PFO (patent foramen ovale), and those that are more open can cause more difficulty.

A patent foramen ovale can predispose you to stroke. Patent foramen ovale is also more common in people who have migraine with aura, about twice as common as in the general population. People with PFO also have a higher rate of migraine with aura.

Why are PFO and migraine with aura connected? One theory is that if there is shunting of blood from the right side of the heart to the left because of a PFO, less blood goes through the lungs to be filtered. This results in a higher level of migraine triggers in venous blood, although it is not clear if those are activated platelets (which contain serotonin) or other chemical triggers. It is not clear, however, if this is the cause, or if the association is non-causative, such as coexistence of the two conditions because both were inherited. In larger PFOs, and a related condition called ASD (anteroseptal defect), there is autosomal dominant inheritance.

About 25-27% of the general population has a patent foramen ovale. The rate is higher in migraine with aura.

Should PFO Be Treated?

Whether PFO in migraine should be treated with closure is not clear. There are several devices that can be inserted via cardiac catheter to close the hole. Several studies have suggested that closure might result in a reduction of migraine attacks. However, there have been flaws in the way these studies were done. Until further studies determine that the benefits of closure outweigh the risks, closure of patent foramen ovale is not recommended.

references:

1. Wilmshurst P, Nightingale S. Relationship between migraine and cardiac and pulmonary right- to-left shunts. Clinical Science 2001;100:215-220.     
2. Wilmshurst P, Pearson M, Nightingale S. Re-evaluation of the relationship between migraine and persistent foramen ovale and other right-to-left shunts. Clinical Science 2005;108:365-367.
3. Post MC, Thijs V, Herroelen L, Budts WIHL. Closure of a patent foramen ovale is associated with a decrease in prevalence of migraine. Neurology 2004;62:1439-1440.                                                                                                                                                                                          
4. Schwerzmann W, Wiher S, Nedeltchev K, et. al. Percutaneous closure of patent foramen ovale reduces the frequency of migraine attacks. Neurology 2004;62:1399-1401.                                                                                                                                                                                               
5. Wammes‐van der Heijden EA, Tijssen CC, Egberts ACG. Right‐to‐left shunt and migraine: the strength of the relationship. Cephalalgia. 2006;26(2):208-213.

                                                                                                                                                                                         6. Tobis J. Management of patients with refractory migraine and PFO: Is MIST I Relevant? Catheterization and Cardiovascular Interventions. 2008;72(1):60-64.                                                                                                                                                                                             7. Taylor FR, Tepper SJ, Stillman MJ. Recent Studies on PFO and Migraine: Is There a Future for Closure? Headache: The Journal of Head and Face Pain. 2008;48(7):1083-1086.

by Christina Peterson, M.D.

updated June 11, 2011