Ultrasound guided patent foramen ovale (PFO) closure has traditionally utilized transoesophageal echocardiography (TOE) under general anaesthesia. Some centres use fluoroscopic guidance alone to facilitate day case PFO closure. Intracardiac echocardiography (ICE) is performed via femoral vein access using an 11 Fr sheath providing accurate guidance without the necessity for general anaesthesia. The safety and feasibility of PFO closure using ICE guidance as a day case procedure have not been documented. We present a consecutive series of patients undergoing planned day case PFO closure under ICE guidance with transthoracic echocardiogram (TTE) follow up. Patients excluded from day case PFO closure were those with early pregnancy or unfavourable social circumstances. 53 consecutive adult patients (44.2+/-11.0 years; 24 males) were planned for day case PFO closure facilitated by ICE. Referral indications were stroke or TIA (n=39), peripheral embolism (n=6), decompression sickness (n=7) and severe migraine (n=1). All 53 patients underwent ICE, with 9/53 (17%) having an atrial septal aneurysm. In 5 patients no PFO was found. In the remaining 48 patients, PFO closure was achieved using the HELEX occluder (n=47) or the Amplatzer device (n=1). Mean procedure and fluoroscopy times were 31.0+/-12.4 and 5.3+/-3.9 min respectively. One patient failed same day discharge due to groin haematoma. There were no other complications. At 3 month follow up, 45/48 (94%) had no residual shunt, with 3 patients having small residual shunts on colour flow Doppler. In conclusion, percutaneous PFO closure as a day case procedure is safe and feasible when facilitated by ICE.