Abstract Background Although most patients with early repair of an isolated atrial septal defect (ASD) have resolution of right ventricular (RV) dilatation, some studies show persistent RV dysfunction and reduced maximal exercise capacity in long-term follow-up in a considerable subgroup of patients. Purpose Right ventricular myocardial work (RVMW) is a novel method for non-invasive assessment of right ventricular (RV) function using RV pressure-strain loops. We sought to evaluate RV function by RVMW indexes in adult patients with atrial septal defect (ASD) before and six months after transcatheter closure in order to assess their value compared to RV three-dimensional(3D) volumetric indexes and two-dimensional(2D)-Doppler parameters. Methods Fifteen ASD patients before and after percutaneous closure were studied using a commercially available cardiovascular ultrasound system (Vivid E95, GE Vingmed Ultrasound, Norway). 15 healthy age- and sex-matched subjects were selected as controls. RV volumes and ejection fraction (3D-RVEF) were obtained using a software package (4D Auto RVQ). 2D-Doppler parameters of RV function (fractional area change -FAC-, tricuspid annular plane systolic excursion -TAPSE-, myocardial performance index -MPI-) were calculated. RV global longitudinal strain (RVGLS) was evaluated by tracing the RV free wall and interventricular septum. Pulmonary artery systolic pressure (PASP) was estimated by tracing the tricuspid regurgitation velocity-time integral. RV global work index (RVGWI), RV global constructive work (RVGCW), RV global wasted work (RVGWW), and RV global work efficiency (RVGWE) were analysed. Datasets were digitally stored and analyzed offline using GE EchoPAC Version-R6. Peak oxygen consumption(VO2) derived from symptom-limited treadmill tests was obtained. Results Overall, 3D-RVEF, RVGWI and RVGWE were significantly higher than control group in open ASD (p=0.02) and decreased significantly six months after closure (p=0.03). NYHA class improved from 1.9±0.4 before to 1.2±0.5 after closure (p<0.05). In 5 patients (33%) 3D-RVEF was reduced and RV was dilated compared to controls six months after closure (p=0.04 and p=0.02, respectively). RVGWI was significantly correlated with RVGLS (p<0.001), PASP (p=0.002), and TAPSE (p=0.014). By multivariate analysis RVGWE and 3D-RVEF were independent predictors of functional class. ROC analysis showed RVGWE and 3D-RVEF (AUC 0.8917 and 0.8869, respectively) to be more sensitive predictors of unfavorable outcome after defect closure (VO2 ≤16mL/min/kg) compared to FAC, TAPSE, and MPI (AUC 0.7586, 0.7824, and 0.7963, respectively). Conclusions In ASD patients before and after closure, right ventricular myocardial work provides useful insights into the quantitative assessment of RV function. RVMW findings are comparable to RV-3D volumetric parameters as predictors of impaired exercise impairment and more accurate than 2D parameters.
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