{'fraction_non_alphanumeric': 0.015755329008341055, 'fraction_numerical': 0.0018535681186283596, 'mean_word_length': 4.996296296296296, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
“How deficient can the IVC rim be?”

The review of device ASD closure with deficient IVC rims by Remadevi et al in this issue proposes two themes for consideration. One being that Secundum ASD with deficient posterior–inferior atrial septal rim may be an acceptable candidate for device closure using the Amplatz ASO occluder, and the other that specialized TEE views using a partial transgastric location and probe retroflexion may improve TEE imaging of the posterior–inferior atrial septum. Indeed others and our own observations [1] have confirmed the rapid and clear demonstration of the presence, absence, or adequacy of the IVC rim using ICE imaging. The TEE approach is indeed commendable for those limited in their practice to TEE imaging and, it indeed seems to provide a very suitable method to demonstrate this segment of the atrial septum. The authors are obviously very experienced and competent in their ASD device closure practice describing 195 device ASD closures in slightly over a one year period. In their review, they describe 12 ‘‘selected’’ cases of secundum ASD with deficient IVC atrial septal rim. They point out that the cases were selected and excluded some patients with deficient rim who had surgical correction. However, in this series it seems likely that few had complete absence of the IVC rim. One deficiency of the review is that the exact details of amount of IVC rim present was not defined in each case and the exact selection criteria are not clearly defined. It also seems possible that the instance of absent IVC rim pointed out in the TTE images may represent simply a sufficiently tangential parasagittal image that the lower septum was out of the image plane. Thus, it is not clear if any patients included had significant absence of IVC rim or otherwise very thin and floppy rim tissue present. It is in this patient population, if associated with a very large defect in a small child, device closure may not be possible. At least it is not clear that this was accomplished in this patient series. However, clearly the review points out the thoroughness of patient echocardiographic evaluation and the expertise in careful device placement as described by the authors. Yet, it also reports the often encountered complications of device closure in deficient IVC rim patients such as device embolization, device oversizing, residual shunts, and difficulty with proper device placement. Clearly, one can only conclude that such defects should only be attempted by those with significant previous experience to allow proper patient selection. Two patients likely should be excluded from this group of IVC deficient rim patients. One with an additional defect closed with a single large device, and the patient who had previous attempted surgical ASD closure. In our experience, such patients with absent IVC rim and previous surgery are very reasonable candidates for device closure because of the previous surgical scarring that tends to stabilize the area for easy device closure. Finally, because the authors also describe device oversizing, with concerns for wall erosions with the Amplatz ASO, interventionalists must recognize the potential increased risk for wall erosions in such cases.