Identifying a Favorable Morphological Profile for Transcatheter Atrial Septal Defect Closure in Patients With...

Transcatheter closure of secundum atrial septal defects (ASDs) with a deficient posteroinferior (PI) rim is challenging owing to an increased risk of technical failure.

This study aimed to explore morphological characteristics associated with a low-risk profile for procedural success in borderline candidates with PI rim deficiency.

In this retrospective study, we analyzed 34 patients with PI rim deficiency who underwent transcatheter closure attempts, excluding those initially triaged to surgery. Cut-off values for echocardiographic indices, including the defect-to-septal ratio (DSR) and the defect-to-left atrial volume ratio (DLAR), were determined using receiver operating characteristic (ROC) analysis. The diagnostic performance of single versus combined indices was evaluated.

Procedural success was achieved in 29 patients (85%), and technical failure occurred in 5 (15%). Combining DSR and DLAR significantly improved risk stratification compared to DSR alone. Exploratory cut-offs for predicting technical failure were DSR ≥ 61.9% and DLAR ≥ 1.3 mm/mL. Fulfilling at least one low-risk criterion (DSR < 61.9% or DLAR < 1.3 mm/mL) effectively identified a highly favorable cohort, yielding a 100% (23/23) procedural success rate and improving overall diagnostic accuracy to 82%.

Assessing spatial mismatch between the defect and left atrium provides a practical framework for risk stratification in PI rim deficiency. While combined DSR and DLAR criteria identify a potential low-risk profile, these exploratory cut-offs remain hypothesis-generating. This demanding procedure requires extreme caution and meticulous patient selection.