Left Atrial Appendage (LAA) is the main source of left atrial thrombi causing embolic strokes in patients with Non Valvular Atrial Fibrillation (NVAF). Since many patients carry contraindications to Oral Anticoagulation (OAC), percutaneous devices for closure of LAA have been introduced, to avoid peripheral thromboembolism in absence of OAC.From March 2012 to March 2014 we enrolled patients which had permanent and persistent NVAF and high thromboembolic risk with absolute contraindication to OAC. They were subjected to insertion of Boston Scientific Watchman device in LAA under transesophageal and fluoroscopic guide, with continuous heparin administration to maintain constant activated clotting time (ACT) of 300-350 sec and under general anesthesia. Patients were discharged with indication to double antiplatelet therapy with Aspirin and Clopidogrel for 6 months and Aspirin thereafter, avoiding Warfarin at all. Follow-up Transesophageal Echocardiography (TEE) was performed 2 months, six months and 12 months after implantation.