Background: Residual shunting is thought to be a risk factor of recurrent stroke after percutaneous device closure (PDC) of patent foramen ovale (PFO) in patients with cryptogenic stroke. The aim of our study was to assess the relationship between PFO characteristics and the presence of a residual shunt at 6 months follow-up.

Methods: We retrospectively reviewed the transoesophageal echocardiographic (TEE) atrial septum characteristics obtained in 99 consecutive patients (mean age 47 ± 12 yrs) with cryptogenic stroke and PFO who underwent PDC at our institution over a 2 year period. Morphologic parameters before PFO closure (diameter of the base and maximal phasic excursion of atrial septal aneurysm (ASA), PFO diameter, tunnel length, and septum secundum thickness) were evaluated. The presence of a residual shunt was assessed by saline contrast study during transthoracic echocardiography (TTE) and TEE 6 months after PDC.

Results: Significant differences in several PFO anatomic parameters were observed in the 25 patients (25%) presenting with a residual shunt as compared with those without residual shunt (table) No patient experienced recurrent neurologic symptoms.

Conclusion: Large PFO and ASA, and/or highly mobile ASA, are associated with the presence of a residual shunt at follow-up. Whether these findings impact on the risk of recurrent stroke deserve further study.