3D right ventricular strain and shape in volume overload: Comparative analysis of tetralogy of Fallot and atrial septal defect patients

Abstract

RV function assessment is crucial in congenital heart disease (CHD) patients, especially in atrial septal defect (ASD) and tetralogy of Fallot (TOF) patients. Indeed, prognosis substantially differs between TOF and ASD and little is known about 3D deformation and shape in RV volume overload. To assess Right ventricular (RV) remodeling differences between ASD, TOF patients and controls. We prospectively included 55 patients (older than 16 yo) into this case-control study: 19 patients with an ASD (and left-to-right shunt), 15 with TOF and 21 healthy controls. 3D transthoracic RV echocardiographic sequences were acquired. Myocardial tracking was performed by a semi-automatic software. Output RV meshes including spatial correspondences were post-processed to temporally align the data and extract local deformation. Global and local statistics provided deformation and shape patterns for each subject. No difference in RV strain was found between ASD patients and controls. There was a trend toward increased longitudinal strain in patients with small ASD. TOF patients had lower RV area and longitudinal strain, especially in the inferior, lateral wall and in the trabecular septum. TOF patients had predominant circumferential over longitudinal strain. Using curvature indices, differences in RV shape were highlighted between controls and RV volume overload patients whereas there was almost no difference between ASD and TOF patients regarding RV shape, except at the septum. RV inferior and lateral curvatures were strongly correlated to QRS duration ( Fig. 1 ). Volume overload alters RV shape to the same extent in ASD and TOF whereas it has differential effects on strain. In ASD patients the strain is relatively preserved whereas TOF patients had particularly impaired longitudinal strain. Such detailed analyses of strain and shape could help refine RV function assessment in particular in CHD patients.