Abstract The superiority of device closure over medical therapy for the prevention of recurrent stroke in patients with cryptogenic stroke and patent foramen ovale (PFO) was reported in several meta –analyses of randomized controlled trials. The growing number of PFO procedures requires to find alternatives to conventional guidance by transoesophageal echocardiography (TOE) needing general anesthesia. The aim of our study was to assess prospectively the efficacy and safety of a simplified procedure based on trans thoracic echocardiography (TTE) and local anesthesia rather than TOE during PFO closure. Methods Design and study oversight. The IDFFOP study was a French prospective, multicenter cohort study performed in four centers expert in TTE-guided device deployment. All patients had a stroke history, a PFO and a large or moderate right to left shunt defined by the number of microbubbles in the left atrium ( large shunt > 30, moderate : 10 to 30 microbubbles). A(Risk of Paradoxical Embolism) score>5 was required to confirm PFO imputability in stroke history. The primary end point was efficacy of TTE during the transcatheter PFO closure defined as the successful implantation of the device without malposition, without need of TOE, and absence of significant residual shunt at 3-month TTE control. Safety was defined as the absence of any periprocedural complications. Results 280 patients were enrolled from January 2018 to October 2020 ( male sex : 59.5%; Average age 57 years old ). Average ROPE score was 7; Cumulative immediate procedural success with the TTE-guided method was 99%, without any device embolization. However, in 2 patients, TOE was needed to guide device deployment. There was no severe vascular complication, or any ischaemic event during or after the procedure. 6 post-procedure groin hematomas occurred but none needed anyblood transfusion .One patient experienced a transient periprocedural atrial fibrillation. At 3 months there were only 8 (2,8%) residual right to left shunts (3 large, 5 moderate). Conclusion A simplified procedure for percutaneous PFO closure based on TTE and local anesthesia is safe and effective. Randomized controlled trials should be performed to confirm these results.