Endomyocardial Fibrosis Found Incidentally on Cardiac Imaging

Endomyocardial fibrosis (EMF) is a rare disease in the developed world characterized by the fibrosis of the endocardium in one or both of the ventricles causing restrictive-type cardiomyopathy. We present a case of a 47-year-old Chinese female with a past medical history of breast cancer treated in 2014 currently on tamoxifen therapy presented to the cardiology office for multiple presyncopal and syncopal events at rest. She was found to have apical hypertrophic cardiomyopathy (HCM) on echocardiogram. Subsequently, cardiac magnetic resonance imaging (cMRI) showed severe apical hypertrophy without left ventricular aneurysm, and evidence of small apical thrombus with subendocardial enhancement. There was no resolution of the left ventricular thrombus after a year-long course of therapeutic anticoagulation, a finding more consistent with EMF. Though the diagnosis of EMF initially depends on echocardiographic findings, cMRI is an essential imaging modality that allows clinicians to easily differentiate between potential diagnoses with the information that it provides. Early diagnosis, differentiation, and treatment for HCM are important for a good prognosis.