RESUMO
Background: Heart failure concomitant with prolactinoma is extremely rare. Case summary: We present the case of a 29-year-old man who had acute decompensated heart failure concomitant with visual loss in his right eye. Transthoracic echocardiography indicated severely decreased left ventricular (LV) function. A massive tumour on the sella turcica was detected by brain computed tomography. The findings of the laboratory tests showed hyperprolactinaemia with hypopituitarism, and the antigen test for coronavirus disease 2019 was positive as an incidental finding. Medication for heart failure and cabergoline therapy were started immediately. His LV function significantly improved, and he had no symptoms after a year. Discussion: Prolactinoma in men, which can cause visual loss and hypopituitarism, is frequently substantial when diagnosed. The cardiac manifestation of prolactinoma is uncommon. It is believed that a major contributing component to the pathogenesis of peripartum cardiomyopathy is hyperprolactinaemia. Hyperprolactinaemia may cause endothelial damage and cardiomyocyte dysfunction, eventually resulting in LV dysfunction. The success of LV reverse remodelling may be significantly impacted by heart failure and hormone treatments. Heart failure and endocrine therapy should be administered concurrently to patients who have prolactinoma and congestive heart failure.