Background: The aim of study is to identify the dependence of right ventricular (RV) free wall longitudinal deformation on ventricular loading through segmental approach in relatively large number of patients with atrial septal defect (ASD).
Methods: Patients with ASD (n = 114) and age matched healthy children (n = 60) were echocardiographically examined the day before percutaneous device closure and within 24 hours afterwards. RV free wall deformation parameters, strain (є) and strain rate (SR), were analyzed in the apical (єA, SRA) and basal (єB, SRB) segments. Measured deformation parameters were adjusted for RV size (єAL, SRAL, єBL, SRBL) by multiplying by body surface area indexed RV longitudinal dimension. Regression analyses determined the relationships of these deformation parameters with RV loading parameters that were measured by catheterization.
Results: єBL and SRBL were not different between pre-closure patients and controls (p = 0.245, p = 0.866), and were decreased post-closure (p = 0.001, p = 0.018). Post-closure єBL was lower than in controls (p = 0.001). Pre-closure єAL and SRAL were higher than in controls (p = 0.001, p < 0.001), but decreased after closure (all p < 0.001). The pulmonary to systemic flow ratio was related to procedural differences of єBL (p = 0.017) and of SRBL (p = 0.019). RV end diastolic pressure was negatively related to post-closure єBL (p = 0.020) and post-closure SRBL (p = 0.012), and the procedural SRBL difference (p = 0.027).
Conclusion: The longitudinal deformation of the RV basal segment is dependent and its remodeling is also dependent on volume loading in children with ASD.
Keywords: Atrial septal defect; Deformation imaging; Right ventricular function; Strain; Strain rate.