INITIAL CLINICAL-RESULTS WITH THE AMPLATZ ER SEPTAL OCCLUDER - A SELF-CENTERING DOUBLE-DISC DEVICE FOR THE OCCLUSION OF ATRIAL SEPTAL-DEFECTS

In recent years many different systems for transcatheter closure of an atrial septal defect (ASD) have been developed and tested. However, a ll systems presently available have some special disadvantages. The re cently introduced Amplatzer Septal Occluder (ASO), though, appears pro mising. It is a self-expanding and self-centering double disc made fro m a Nitinol mesh, which is tightly woven to give mechanical strength. Both discs are separated by a connecting cylindrical portion. Its diam eter may be chosen, so that it corresponds to that of the ASD. Discs o f polyester patches are sewn into the retention discs as well as into the cylindrical portion of the device in order to augment thrombogenic ity. After measuring the diameter of the ASD with a balloon, an approp riate ASO is selected and advanced into the left atrium through a 7 or 8 French sheath. Then the distal disc and part of the connecting cyli ndrical portion is developed in the left atrium and pulled against the atrial septum, so that the cylindrical portion is occluding the ASD. Thereafter, proximal disc is deployed and the delivery cable disconnec ted. As long as the cable is connected to the device repositioning is easily achieved by pulling the device back into the sheath. Within a t ime period of 4 months in 29 out of 31 patients (median age: 12.1 year s, median weight: 45.0 kg) complete closure of the ASD with a mean dia meter of 11.0 mm (6-20 mm) was achieved without complications, the ave rage fluoroscopy time being 8.3 min (2.9-21.5 min). Mean Qp:Qs was 1.5 (0.9-2.2). During a mean follow-up period of 2.1 months post implanta tion fixed seating of the ASO without residual shunt, arrhythmias, thr ombembolic events and impairment of A-V valves was observed in all pat ients. Conclusion: The Amplatzer septal occluder allows quick, safe, a nd complete closure of atrial septal defects without complications if one adheres to strict implantation criteria. For a final judgement, ho wever, long-term follow-up studies are necessary.