Atrial Late Gadolinium Enhancement in Patients With Repaired Congenital Heart Disease

In this research study the investigators want to learn more about how well the investigators can visualize scar tissue in the heart by MRI. In patients with congenital heart disease who need a procedure in the electrophysiology laboratory, how the MRI findings match the findings in the electrophysiology laboratory is not known. This study works to answer these questions. Participants will undergo a cardiac MRI as part of the routine clinical care that was ordered by their doctors and additional imaging by cardiac MRI will be performed.

Inclusion Criteria: * Patients \>13 years old with congenital heart disease referred for cardiac MRI and receiving gadolinium as part of routine clinical care or for pre-ablation planning will be included. Exclusion Criteria: * Those with self-reported anxiety or claustrophobia and/or the presence of a permanent pacemaker or implantable cardioverter defibrillator will be excluded.