This report describes the clinical course and multi-modality imaging findings in an anti-SSA-antibody-exposed fetus with suspected myocardial inflammation. Postnatal cardiac MRI – using fast acquisition, free-breathing with feed-and-swaddle technique – was used to evaluate for myocardial fibrosis/inflammation. This is the first published report, to our knowledge, of ductal constriction temporally associated with oral dexamethasone therapy in an anti-SSA-antibody-exposed fetus and of the use of this unique postnatal MRI protocol in this setting.