Safety and efficacy of transcatheter closure of atrial septal defects guided by transthoracic echocardiography: a prospective study from two Chinese Medical Centers.

The purpose of this study was to evaluate the safety and efficacy of transcatheter atrial septal defect (ASD) closure guided by transthoracic echocardiography (TTE). A total of 191 patients with ASD were recruited from two Chinese medical centers and TTE was carefully performed in multiple views to observe ASD number, position, diameter and relation with adjacent cardiac structures. All patients were divided into three groups based on their largest ASD diameters: 66 subjects with ASD diameter 5-14 mm (group A); 60 subjects with ASD diameter 15-20 mm (group B); and 65 subjects with ASD diameter 21-38 mm (group C). Atrial septal occluders (ASOs) were successfully deployed in 188 patients (98.4%) and ASD was successfully closed at 6-mo follow-up in 185 patients (96.9%). The difference between diameters of ASO and ASD (ASO-ASD) in groups A, B and C were 3.9 +/- 2.4 (0-7) mm, 5.0 +/- 2.6 (3-8) mm and 6.2 +/- 3.8 (5-11) mm, respectively. In group A, no complications occurred. In group B, only four patients had mild complications such as sinus bradycardia, transient hematuria and migraine, all of which disappeared after treatment. In group C, one patient developed ASO migration into the right atrium and two patients had their ASO migrated into the right ventricular outflow tract. Immediately after the closure, 60 (90.9%), 53 (88.3%) and 53 (82.8%) patients had complete ASD closure; 2, 4 and 6 patients had trivial residual shunts; 4, 3 and 2 patients had small residual shunts; and 0, 0 and 2 patients had moderate residual shunts in groups A, B and C, respectively. Most of the residual shunts were persistent at 6-mo follow-up. No embolism or death at procedure and 6-mo follow-up occurred. In conclusion, TTE is a reliable technique for measurement of ASD diameter, guidance of transcatheter ASD closure and evaluation of residual shunts. Transcatheter ASD closure guided by TTE is safe and effective, especially in patients with ASD <or=20 mm.