Right Ventricular Remodeling after Transcatheter Closure of Atrial Septal Defect

Background: Right ventricular (RV) volume overload is a well-known cardiac consequence of atrial septal defect (ASD) shunt, accounting for most of its long-term complications. Thus cardiac volumetric unloading is a major aim of transcatheter ASD closure. We set to study the right ventricular remodeling after transcatheter ASD closure in patients with secundum ASD. Methods: We enrolled 46 patients who underwent successful transcatheter closure of ASD. We performed routine transthoracic echocardiographic studies, including three-dimensional echocardiography and right ventricular myocardial performance index (RVMPI), before transcatheter ASD closure, and 3 days, 1 month after transcatheter ASD closure. Results: We found that: (1) the right ventricular end-diastolic volume (RVEDV) and right ventricular end-systolic volume (RVESV) (respectively 106.54 +/- 25.97 vs 69.78 +/- 10.46 mL, P < 0.05; 59.73 +/- 17.59 vs 33.84 +/- 7.18 mL, P < 0.05) were enlarged in patients with ASD compared with those in control subjects, resulting in a marked decrease of the right ventricular ejection fraction (RVEF) (44.82% +/- 4.51% vs 54.11% +/- 5.89%, P < 0.05) from normal values; (2) the isovolumic relaxation and isovolumic contraction times (respectively [77.61 +/- 16.49] ms vs (64.09 +/- 11.82) ms, P < 0.05; [28.04 +/- 9.57] ms vs [20.45 +/- 6.53] ms, P < 0.05) were prolonged and ejection time ([250.02 +/- 24.21] ms vs [272.73 +/- 20.51] ms, P < 0.05) was shortened in patients with ASD compared with that in control subjects, resulting in a marked increase of the MPI (0.41 +/- 0.07 vs 0.31 +/- 0.05, P < 0.05) from normal values; and (3) after transcatheter closure, the RVEDV and RVESV decreased and the RVEF increased markedly and RVMPI decreased markedly. Conclusions: Transcatheter closure of ASD results in rapid normalization of RV volume overload and improvement of RV function. (ECHOCARDIOGRAPHY, Volume 26, November 2009)