Residual Shunt after Patent Foramen Ovale Closure: Preliminary Results from Italian Patent Foramen Ovale Survey

Background: Percutaneous patent foramen ovale (PFO) closure is accepted as treatment for cryptogenic ischemic stroke/transient ischemic attack in young subjects. However, a thorough evaluation of residual right-to-left shunt (rRLS) after PFO closure is needed. Our aims were to analyze the characteristics related to PFO diagnosis and closure, focusing on rRLS and clinical recurrences until 24-month follow-up. Data were extrapolated from the 12-month Italian PFO Survey. Methods: In all, 1035 patients were included. PFO diagnosis and right-to-left shunt (RLS) were assessed by contrast-enhanced transesophageal and/or transthoracic echocardiography and/or transcranial Doppler. Results: PFO diagnosis with RLS data were available in 894 of 1035 (86.4%) patients. rRLS was investigated in 49.6% (6 months), 27.1% (12 months), and 3.5% (24 months), and observed in 19.5% (6 months) and 18.2% (12 months) of subjects. Large permanent rRLS was observed in less than 3% of RLS-positive patients after 1 year. Eleven of 14 and 3 of 14 neurological recurrences were observed in 10 of 444 (2.25%) and 2 of 243 (0.8%) patients within the 6- and 12-month follow-up, respectively. Among these, no large rRLS was reported. There were no neurological events at 2-year follow-up. Forty of 444 subjects had non-neurological complications, mostly cardiac arrhythmias within the sixth month. Conclusions: PFO closure is a safe procedure. rRLS is not uncommon but large rRLS is rare. Clinical complications, mostly related to cardiac arrhythmias, are not unusual. Evaluation of the data of the whole survey is underway.