Second transcatheter closure for residual shunt following percutaneous closure of patent foramen ovale

Aims: Residual shunt following percutaneous patent foramen ovale (PFO) closure has been described in up to 49% of patients and is associated with recurrent cerebrovascular events. Our aim was to evaluate the safety, feasibility, and midterm outcomes of transcatheter residual shunt closure. Methods and results: From 1994 to July 2016, 2,679 patients underwent transcatheter PFO closure for treatment of presumed paradoxical embolism at our institution. Among them, 100 patients (3.7%) were referred for residual shunt closure. They constituted the study population for which a retrospective analysis of the prospectively gathered procedural data was performed along with prospective acquisition of follow-up data. The indication for initial PFO closure was an ischaemic cerebrovascular event in 85% of the patients. Patients underwent transoesophageal echocardiography (TOE) for PFO diagnosis and again for residual shunt assessment at about six months. All procedures were performed under fluoroscopic guidance only. At the first procedure, 10 different devices had been used. The AMPLATZER PFO Occluder accounted for 54% and the AMPLATZER Cribriform Occluder for 28%. Compared to the whole population (n=2,679), a significantly higher rate of atrial septal aneurysm (58% versus 36%; p=0.024), a larger implanted device (47% versus 13%; p<0.001) were observed in the patients with residual shunt. Six patients (6%) experienced a recurrent TIA or ischaemic stroke before the second intervention. Residual shunt closure was successful in all but two patients. A second AMPLATZER PFO Occluder was used in the majority of the repeat interventions (76%). There were no complications. TOE, obtained again after 7 +/- 5 months in 88 of the 98 patients with a device in place (90%), showed complete closure in 81%. In eight patients (0.3% of the whole cohort), a third device was implanted, resulting in complete closure in all. Conclusions: Transcatheter residual shunt closure after initial percutaneous PFO closure can be safely performed under fluoroscopic guidance only and achieves complete closure in most patients. The use of larger devices, typically prompted by intricate anatomy, represents a risk factor for shunt persistence and the need for reintervention.