Atrial septal defect (ASD) is the most common adult congenital heart disease. The left-to-right shunt causes a right ventricular (RV) volume overload. Only little is known about RV remodeling after ASD closure.

We aimed to assess RV function using 2D, 3D echocardiography and 3D RV strain before and 1 month after ASD closure.

We prospectively included in this monocentric study 9 patients with secundum ASD who underwent percutaneous closure between September 2019 and January 2020. 2D and 3D Echocardiography were performed in all patients before and 1-month after closure. While we initially planned to collect echocardiographic data 3- and 6-months after ASD closure, the COVID-19 pandemic made this impossible. All patients gave their informed consent to the study. Clinical and ultrasound data were collected and anonymized. 3D RV echocardiographic sequences were analyzed by semi-automatic software (Tomtec 4D RV Function, Unterschleissheim, Germany) and output meshes were post-processed to extract regional deformation.

Patients’ mean age was 31.0±12.3 years, 44.4% were female. Mean ASD diameter was 16.6±7.4mm. RV end diastolic diameter and right atrial (RA) area were significantly larger than normal values and decreased significantly after ASD closure (45.8±4.9 vs. 37.8±5.7mm; P=0.0009 and 21.4±4.2 vs. 16.3±2.7cm²; P=0.01, respectively). 3D RV volumes were significantly lower after ASD closure; respectively 156.3±61.7 vs. 82.9±17.40mL, P=0.02 for end diastolic volume and 59.4±19.3 vs. 32.6±9.2mL, P=0.01 for end systolic volume. RV function decreases after ASD closure as illustrated by TAPSE (23.3±6.0 vs. 29.1±4.2mm, P=0.03) as well as 3D RV strain with a significantly decreased in area strain, longitudinal strain as well as circumferential strain (respectively P=0.006, P=0.009 and P=0.02) (Fig. 1).

After percutaneous ASD closure, we demonstrate a decrease in RV function in all strain components using 3D strain. This decrease in RV strain probably illustrates the decrease in RV parietal stretch related to the normalization of RV loading conditions. 3D strain can be useful to assess the RV function evolution in response to different loading conditions.