Aims: Using balloon sizing to determine device size may cause complications and increase procedure time in performing transcatheter closure of atrial septal defect (ASD). We aimed to validate the clinical utility of a formula using measurements from 3D transoesophageal echocardiography (TOE) images in performing the procedure without balloon sizing.
Methods and results: We enrolled 248 consecutive patients with ASD in a prospective registry. In the first tier (n = 53), we determined the device size before the procedure using our formula and performed balloon sizing during the procedure to verify our decision. In the second tier (n = 195), the procedure was performed without balloon sizing. In the first tier, the estimated device size correlated well with the device size finally implanted (R = 0.961, P < 0.001; bias, 0.38 ± 1.5 mm, P < 0.001) and with the stretched balloon diameter (R = 0.929, P < 0.001; bias, 0.13 ± 2.0 mm, P < 0.001). In the second tier, the device size derived from the formula was used in all patients, with the exception of one patient who showed a deficient rim on the aorta and superior sides and ASD that was not on a single plane. Two patients with unfavourable morphologies for device implantation experienced embolization of the device. Of the 193 patients with procedural success (99.0%), 2 suffered from haemopericardium caused by atrial wall erosion by the device. There were no procedure-related deaths.
Conclusion: The transcatheter closure of ASD using the 3D TOE-derived formula without balloon sizing is clinically feasible and safe. However, caution should be taken to exclude unfavourable features of ASD (ClinicalTrials.gov number NCT 02097758).
Trial registration: ClinicalTrials.gov NCT02097758.