Thyrotoxicosis-induced cardiomyopathy and consequent heart failure is one of the most grave complications of uncontrolled hyperthyroidism. In such patients, early recognition of thyrotoxicosis, and directed antithyroid therapy can lead to rapid normalization of left ventricular function. Herein, we present a case of a 29-year-old male with Graves' disease who developed heart failure with severe deterioration of left ventricular function and eventually, circulatory collapse. Height and weight of the patient were 1.8 m and 84 kg, respectively. The patient was placed on venoarterial extracorporeal membrane oxygenation for immediate circulatory support, with restoration of cardiac function after 6 days.