Transcatheter closure of atrial septal defect and patent foramen ovale with the ASDOS device (A Multi-Institutional European Trial)

A clinical trial was conducted to assess the feasibility, safety, and effic acy of the atrial septal defect (ASD) occlusion system for transcatheter cl osure of secundum ASD and patent foramen ovate (PFO) after episodes of cere bral embolism. Occlusion was attempted in 200 patients aged 1 to 74 years ( mean 32). The procedure failed in 26 patients (13%); the device was retriev ed through a catheter in 20 and through surgery in 6 patients. procedure-re lated complications necessitating surgical removal of the device included d evice embolization in 2, device entrapment within the Chiari network in 1,f rame fracture in 1,and perforation of atrial wall in 2. All 6 patients expe rienced an uneventful postoperative course. An additional 11: patients (6%) underwent surgical removal of the device during follow-up. There were 163 patients (81%) with an implanted ASD occlusion system at follow-vp of from 6 to 36 months (mean 17). Thrombus formation around the device was detected by transesophageal echocardiography in 9 patients 1 to 4 weeks after impla ntation. One of these patients (who had a coagulation factor XII deficiency ) suffered a cerebral thromboembolism. Late atrial wall perforation (5, 6, and 8 months after implantation) occurred in 3 adult patients. Infectious e ndocarditis developed in 2 adult patients (1%). No late device embolization and no atrioventricular valve injury occurred. An asymptomatic device fram e fracture was found in 14% and frame deformity in 4% of all patients durin g the follow-up period of >230 patient-years. Immediately after closure, a moderate/large residual shunt remained in 8% and a small shunt in 29% of pa tients. After 1 year, a moderate/large shunt was present in 2% and a small one in 26% of patients. During a total follow-up of 49 patient-years, only 1 of 46 patients with PFO had a transient neurologic event after the closur e. The study indicates that patients with centrally situated secundum ASD a nd those with PFO after cerebral embolism can be treated with this system w ith a high success rate and an acceptable morbidity. (C) 1998 by Excerpta M edica, Inc.