Intracardiac Echocardiography Evaluation in Secundum Atrial Septal Defect Transcatheter Closure

Purpose: This study was designed to assess the balloon sizing maneuvers and deployment of an Amplatzer Septal Occluder (ASO). In addition, intraprocedural balloon sizing was compared with off-line intracardiac echocardiographic measurements. Methods: The intracardiac echocardiography (ICE) measurements were: maximum transverse and longitudinal atrial septal defect (ASD) diameters in the aortic valve and four-chamber planes; area of the ASD and its equivalent circle diameter. Thirteen consecutive patients underwent transcatheter implantation of an ASO device using ICE guidance under local anesthesia. The device matching the balloon sizing diameter of the defect was implanted. Qualitative ICE assessment of the ASO devices implanted was performed off line. Results: The mean equivalent circle diameter predicted by ICE was 24.40 ± 5.61 mm and was significantly higher (p = 0.027) than the ASD measured by balloon sizing (21.38 ± 5.28 mm). Unlike previous studies we did not find any correlation between the two measurements (correlation coefficient = 0.47). Only four of the 13 patients had optimal device positioning as shown by the qualitative ICE evaluation, whereas the remaining nine patients had inadequate device placement. This resulted in a waist diameter that was an average 26.1% undersized in seven patients and 12.7% oversized in two patients. Five of the seven patients with an undersized device had ASO-atrial septum misalignment with leftward device deviation. Conclusion: The ICE images allowed careful measurement of the dimensions of the ASD and accurately displayed the spatial relations of the ASO astride the ASD. Moreover, use of the ICE measurement led to selection of a different size of device in comparison with those of balloon sizing. The clinical benefit of this new approach needs to be rigorously tested.