Recurrent and residual shunts after patent foramen ovale closure: Results from a long-term transcranial doppler study

Objectives Assess the evolution of right-to-left shunt (RLS) after transcatheter patent foramen ovale (PFO) closure. Background Despite the high number of interventional procedures performed worldwide, limited systematic data on the long-term abolition of RLS after percutaneous closure are available. Methods All patients treated at our Institution between February 2001 and July 2009 were included in this single center, prospective study, and were asked to repeat late contrast transcranial Doppler (cTCD). Rate of complete closure, residual RLS (i.e., a shunt that persists after closure), and recurrent RLS (i.e., a shunt that reappears after a previous negative cTCD) was assessed. Results Long-term follow-up was completed in 120 patients (56% male). RLS was still detectable 4.9 ± 2.3 years (range 1.3-10.3) after the procedure in 55 patients; 20 (17%) had residual RLS and 35 (29%) had recurrent RLS. Multivariate analysis revealed that significant predictors of residual RLS included post-procedural shunt at transesophageal echocardiography (OR 3.07, 95%CI 0.97-9.7), use of a bigger device (35 vs 25 mm, OR 3.85, 95%CI 1.22-12.2) and length of follow-up (OR 0.75, 95%CI 0.57-0.98), while only length of follow-up (OR 0.77, 95%CI 0.62-0.95) was associated with recurrent RLS. Neurological recurrences (1 stroke, 6 transient ischemic attacks) were equally distributed between the groups. Conclusion A significant number of recurrent and residual shunts may be observed by cTCD up to 5 years after PFO closure. Management of late RLSs includes periodic re-evaluation, exclusion of device-induced complications or secondary sources of RLS, and optimization of antithrombotic treatment with or without a second intervention.