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.