Nutritional deficiencies of vitamins and minerals have been associated with reversible and irreversible cardiomyopathic processes. Selenium deficient dilated cardiomyopathy, first described in 1935 in the Keshan Province of China, was sometimes reversed with selenium supplementation. In the past three decades, selenium deficient cardiomyopathy has re-emerged in western medicine secondary to gastrointestinal disorders, long-term total parenteral nutrition (TPN) and gastrointestinal surgery. This report describes a case of selenium deficient cardiomyopathy secondary to the bariatric (weight loss) surgical operation bilio-pancreatic diversion (Scopinaro procedure). This patient presented with life-threatening heart failure nine months after this surgery, having lost 100 kg of body weight. Multiple nutritional deficiencies were detected and corrected including severely depleted selenium levels. Cardiac function and the clinical scenario improved dramatically over three weeks. Screening patients at risk of malnourishment for selenium deficiency as a potential cause of cardiomyopathy is indicated.