Cardiac magnetic resonance imaging in atrioventricular discordance and congenitally corrected transposition (CCTGA).

Patients with congenitally corrected transposition of the great arteries (CCTGA) have a heterogenous anatomy due to the altered ventricular topology and associated malformations, leading to a diverse range of management options. Crucially the dichotomous decision of whether to continue with the right ventricle as the systemic ventricle or to perform complex inflow and outflow re-routing surgery, restoring the left ventricle to its role as the systemic ventricle will determine the patient's future care. Using the protocol of a tertiary cardiac surgery centre we describe how cardiac MRI provides a uniquely accurate combination of anatomical and functional data about the complex native cardiac and extra-cardiac anatomy prior to operation. MRI provides a non-invasive and non-ionising modality without the limitations of echocardiography 'acoustic windows'. We describe how to assess CCTGA from infancy to adulthood including the patency of the venous baffle pathways, re-routed outflow pathway and residual lesions/complications in post-operative patients. MRI also allows the study of tissue characterisation in our aging congenital heart disease population and is well-established in the lifelong surveillance and assessment of the systemic right ventricle across the world.