Evaluating Right Ventricular Hemodynamics in Patients with Repaired Tetralogy of Fallot via Four-Dimensional Flow CMR

Motivation: Repaired tetralogy of Fallot (rTOF) carries an increased risk of chronic volume overload-induced right ventricular dysfunction. Goal(s): To assess right ventricular hemodynamics in rTOF patients using four-dimensional flow cardiac magnetic resonance. Approach: Flow components and kinetic energy were analyzed in 30 rTOF patients and 30 healthy controls. Direct flow, delayed ejection flow, kinetic energy normalized to end-diastolic volume, and global peak strains were measured. Results: rTOF patients exhibited abnormal right ventricular effective blood flow components and kinetic energy. Direct flow and global peak longitudinal strain demonstrated higher diagnostic efficacy for right ventricular remodeling than right ventricular ejection fraction. Impact: Four-dimensional flow cardiac magnetic resonance offers a novel imaging biomarker for assessing declines in right ventricular efficiency and monitoring disease progression in rTOF patients, with robust potential for use in patient follow-up and disease surveillance.