Distinct remodeling patterns after ASD and PFO closure: a comparative atrial strain and myocardial work analysis - initial results

Background Atrial septal defect (ASD) and patent foramen ovale (PFO) are prevalent forms of interatrial communications associated with paradoxical embolism and right heart volume overload. Transcatheter closure is a guideline-recommended treatment strategy for selected patients. Advances in echocardiographic imaging, such as myocardial work (MW) and atrial strain analysis, offer enhanced insight into cardiac performance beyond conventional volumetric measures. Purpose This study aimed to assess longitudinal changes in left ventricular (LV) MW and atrial function in patients undergoing percutaneous closure of ASD or PFO, and to compare these parameters between the groups at baseline, 1 month, and 6 months post-procedure. Methods This observational study included 34 patients (27 with PFO and 7 with ASD) undergoing transcatheter closure of an interatrial shunt. Transthoracic echocardiography was performed before the procedure, and at 1 and 6 months of follow-up. Left atrial (LA) strain was assessed using speckle-tracking echocardiography, including reservoir (LASr), conduit (LAScd), and contractile (LASct) strain, with additional biatrial (LA+RA) analysis. LV MW indices, including global longitudinal strain (GLS) and global work index (GWI), were calculated using non-invasive pressure–strain loop methodology. To ensure measurement accuracy, the interatrial septum, containing occluder material post-implantation in all patients, was excluded from the region of interest during atrial strain analysis. Results In the ASD group, a significant reduction in right ventricular (RV) diameter was observed at 1 month (49.4 ± 5.2mm to 42.3 ± 5.9mm; p<0.001) and at 6 months (39.8 ± 2.4mm; p=0.04). A significant reduction in combined biatrial reservoir strain (LA+RA Sr) was noted at 1 month (p=0.026), with a trend toward normalization at 6 months. In the PFO group, GLS improved at 1 month from -19.2 ± 2.4% to -20.1 ± 2.4% (p=0.038). No significant changes were observed in LA strain or MW indices. Baseline comparison revealed significantly larger RV diameters (49.4 ± 5.2mm vs. 37.2 ± 5.9mm; p<0.001) and lower LVESV (39.6 ± 5.3mL vs. 49 ± 16mL; p=0.011) in ASD versus PFO patients. These differences persisted at 1-month follow-up. Additionally, patients with ASD demonstrated significantly reduced LASr (22.2 ± 4.2% vs. 34.1 ± 7.5%; p<0.001), LASct (-9.2 ± 6.5% vs. 14.3 ± 4.3%; p=0.02), and combined biatrial strain indices (LA+RA reservoir: 23.5 ± 5% vs. 33.3 ± 7.4%; p=0.005; conduit: –12.5 ± 5.7% vs. –20.6 ± 7.2%; p=0.012). By 6 months, intergroup differences diminished, except for persistently larger RV size in the ASD group (39.8 ± 2.4mm vs. 35.2 ± 3.7mm; p=0.02). Conclusions Transcatheter closure of interatrial communications results in distinct patterns of cardiac remodelling. ASD closure was associated with RV reverse remodeling and transient biatrial dysfunction. In contrast, no significant atrial strain changes were observed in PFO patients.