Patients with PFO, who meet all the inclusion and none of the exclusion criteria, will be enrolled in the study. Patients will undergo percutaneous correction of PFO and the following evaluations as clinical practice:
* thrombophilic screening (factor V and II and MTHFR gene mutation); sampling for homocysteine, Protein C (Prot C), Protein S (Prot S) and antithrombin III assay;
* anatomic evaluation of the SIA (Saccular intracranial aneurysm) by color-doppler TT echocardiogram and intracardiac ultrasound for definition of the anatomy of the fossa ovalis: tunneled appearance; absence of SIA aneurysm; bulging of the SIA; convex right/left SIA aneurysm;
* quantification of right-left intracardiac shunt by CT doppler;
* classification of migraine according to Anzola scale at baseline visit, post PFO correction, at follow-up at 6 and 12 months.
For the purpose of the study, blood sampling will be performed for evaluation of platelet reactivity; oxidative stress, aggregability, and deformability of red blood cells; and isolation of Endothelial Colony Forming Cells (ECFCs) for analysis of endothelial function. The latter in particular will be evaluated in comparison with the endothelial function of 30 subjects without known disease with age \> 18 years, enrolled as a control group.
All analyses will be performed before PFO correction and 180 days after surgery.
