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

Reliability of transthoracic echocardiography in estimating the size of Amplatzer septal occluder and guiding percutaneous closure of atrial septal defects.

BACKGROUND: In China, transthoracic echocardiography (TTE) is popularly used for pre-intervention examination for atrial septal defect (ASD) and for guiding ASD closure. However, the ability to determine ASD size and the safety and efficacy of TTE for guiding ASD closure still has not been widely accepted. This study aimed to evaluate the efficacy and safety of TTE used before, during and after transcatheter ASD closure with Amplatzer septal occluders (ASO). METHODS: Sixty-eight subjects (15 men and 53 women; mean age (33.7 +/- 17.3) years) were enrolled. TTE was used to measure the diameters and guide transcatheter closure of ASD. The ASD was examined by long-axis view, basal short-axis view, apical four-chamber view and the subcostal view to observe position, diameter and relation with neighbouring structures. The largest diameter was selected as the reference diameter. Patients were divided into 3 groups according to the ASD reference diameter: 22 subjects with ASD diameter 4 - 14 mm (group A); 21 subjects with ASD diameter 15 - 20 mm (group B); and 25 subjects with ASD diameter 21 - 33 mm (group C). RESULTS: ASD was occluded successfully in groups A and B. In group C, occlusion failed in 2 cases; 1 case remained with a 3-mm residual shunt sustained until 6-month follow-up. However, at 6-month follow-up, no case of thromboembolism, ASO dislocation or death occurred in the three groups. The diameter of ASD measured by TTE could accurately predict the ASO size that could successfully occlude the ASD, especially in patients with ASD < 20 mm. The ASD diameter measured by TTE correlated well with ASO size (r = 0.925, P < 0.001; r = 0.976, P < 0.001; r = 0.929, P < 0.001 respectively). CONCLUSIONS: ASD diameter measured by TTE can accurately estimate the size of the ASO needed for successful closure of ASD. The larger the ASD, the much larger the ASO needed. TTE is a satisfactory guiding imaging tool for ASD closure.