Measurement of Atrial Septal Defect Size: A Comparative Study between Transesophageal Echocardiography and Balloon Occlusive Diameter Method

BACKGROUND Transcatheter closure of atrial septal defect secundum (ASD-II) has become an alternative method for surgery. We sought to compare the two-dimensional transesophageal echocardiography (TEE) method for measuring atrial septal defect with balloon occlusive diameter (BOD) in transcatheter ASD-II closure. METHODS A total of 39 patients (71.1% female, mean age: 35.31 ± 15.37 years) who underwent successful transcatheter closure of ASD-II between November 2005 and July 2008 were enrolled in this study. Transthoracic echocardiography (TTE) and TEE were performed to select suitable cases for device closure and measure the defect size before the procedure, and BOD measurement was performed during catheterization via TEE. The final size of the selected device was usually either equal to or 1 - 2 mm larger than the BOD of the defect. RESULTS The mean defect size obtained by TEE and BOD was 18.50 ± 5.08 mm and 22.86 ± 4.76 mm, respectively. The mean difference between the values of ASD size obtained by TEE and BOD was 4.36 ± 2.93 mm. In comparison with BOD, TEE underestimated the defect size in 94.9%, but TEE value being equal to BOD was observed in 5.1%. There was a good linear correlation between the two measurements: BOD = 0.773 × ASD size by TEE+8.562; r2 = 67.9.1%. A negative correlation was found between TEE sizing and the difference between BOD and TEE values (r = -0.394, p value = 0.013). CONCLUSION In this study, BOD was larger than ASD size obtained by two-dimensional TEE. However, TEE maximal defect sizing correlates with BOD and may provide credible information in device size selection for transcatheter ASD closure.