Cardiac magnetic resonance features of the left ventricle in d-transposition of the great arteries after arterial switch operation: Results from a single center

Background: This study aims to measure and describe left ventricular (LV) volumetric parameters, aortic regurgitation, and strain in patients who have undergone an arterial switch operation (ASO) for d-transposition of the great arteries (d-TGA), and to evaluate the incidence of abnormal cardiac magnetic resonance (CMR) findings in this cohort of patients. Materials and Methods: We retrospectively analyzed CMR in children and adults with repaired d-TGA, post-ASO, who underwent imaging in our center between 2011 and 2019 using the following sequences: Cine steady-state free precession, phase-contrast (PC) flows, and contrast angiograms on a 1.5T scanner. We measured the following parameters: indexed LV end-diastolic and end-systolic volumes, LV ejection fraction (LVEF), and aortic regurgitation fraction (AI%) using PC flows. Two-and 3-dimensional (2d and 3D) LV global radial, circumferential, and longitudinal strain were calculated using Circle cvi42. Results: Fifty-two studies were finally analyzed (male 33%, median age 14.3 years). Nine (17%) had reduced LVEF as measured by CMR. The incidence of late gadolinium enhancement is 9.6%. Among adult patients (for whom normative data are available for comparison), 2D and 3D global LV strain values were within the normal range. Conclusions: CMR characteristics of the left ventricle (including global 2D and 3D strain parameters) and the neo-aortic valve are reassuring late after arterial switch operation in the majority of patients with d-transposition of the great arteries. CMR is particularly useful to detect late gadolinium enhancement.