Time-course of cardiac remodeling following transcatheter closure of atrial septal defect

Background: Right chamber dilatation and right-to-left volumetric unbalance are well-known cardiac consequences of atrial septal defect (ASD) shunt, accounting for most of its long-term complications. Thus, cardiac volumetric unloading is a major aim of ASD closure. Different from surgery, transcatheter option might be considered as an "unbiased" tool to evaluate the cardiac geometric remodeling following ASD closure. Methods: Extent and time-course of cardiac geometric changes were assessed by echocardiography 24 h, I and 6 months after percutaneous closure of large ASD (mean diameter 17 +/- 6 mm, QP/QS 2.2 +/- 0.9) in 42 asymptomatic patients (age 22 +/- 18 years). Results: Transcatheter closure was accomplished using the Amplatzer Septal Occluder device (mean 23 7 mm, median 24 mm), achieving a complete occlusion in all patients at the 6-month follow-up control. After ASD closure, right atrial (RA) volume reduced from 45 24 to 28 +/- 12 ml (-37.8%, p < 0.001), while left atrial (LA) volume did not significantly change. Inlet and infundibulum right ventricular (RV) end-diastolic diameters reduced by 23 +/- 2% and 23 +/- 3%, respectively (p < 0.001 for both measurements), although with a different time-course of changes. Finally, transverse left ventricular (LV) end-diastolic diameter increased from 39 +/- 7 to 44 +/- 5 mm (+11.4%, p < 0.01). These geometric changes resulted in an RV/LV diameter ratio decrease by 34 +/- 3% (p < 0.001). Nearly 90% of cardiac remodeling ensued within I month from shunt disappearance (50% within 24 h). Conclusions: Percutaneous ASD closure results in early and striking cardiac geometric changes that almost completely revert the right-to-left volumetric unbalance. Most of this geometric remodeling ensues within a few weeks from ASD closure. (c) 2005 Elsevier Ireland Ltd. All rights reserved.