A case of acute heart failure due to myocardial infiltration of mycosis fungoides.

Mycosis fungoides (MF) has been reported to be the most common cutaneous lymphoma with a good prognosis and myocardial infiltration is clinically rare. We hereby report a case of rapidly progressing acute heart failure due to myocardial infiltration by MF. Perfusion cardiac magnetic resonance imaging (MRI) demonstrated a massive perfusion defect in the left ventricle (LV) where multiple nodular enhancement areas by delayed enhancement MRI could be documented in the postero-lateral wall of the LV, which resulted in a deterioration of the LV function and mitral regurgitation. Autopsy confirmed the myocardial infiltration by the MF, which corresponded with the MRI findings. <Learning objective: Symptomatic heart failure patients with myocardial infiltration by mycosis fungoides (MF) have a poor prognosis because they could not undergo chemotherapy for primary disease. Therefore, early diagnosis is important for improvement of prognosis. The routine assessment of the cardiac involvement by cardiac magnetic resonance imaging as well as transthoracic echocardiography should be performed for an early recognition of myocardial infiltration even in asymptomatic MF patients.>.