Assessment of right ventricle intracardiac flow in congenital heart disease: Comparison of enhanced echocardiography and 4D flow MRI measurements*

Abnormal flow in the human heart play a crucial role in the pathology of congenital heart defects. Non-invasive flow imaging techniques can aid CHD management, especially 4D flow MRI and color Doppler echocardiography (echo) flow reconstruction. Although both methods have been independently validated against computational models, a comprehensive assessment of flow measurements and hydrodynamics between these methods has yet to be shown. In this presentation, we address the limitations and strategies associated with comparing flow measurements from 4D flow MRI and echo reconstructions. Using a cohort of repaired Tetralogy of Fallot, dilated right ventricles from atrial shunts, and control subjects, we investigate the agreement between these modalities by analyzing velocity magnitude, vorticity, flow energy loss, kinetic energy, and relative pressure fields. Our findings reveal a high correlation (median R ≥ 0.87) and low random differences, demonstrating the potential for obtaining complementary measurements between imaging modalities. These results establish color Doppler echo flow reconstruction as a complementary measurement tool to 4D Flow MRI to reliably resolve underlying intracardiac flow patterns.