Takotsubo cardiomyopathy and cardiogenic shock due to hypokalaemic rhabdomyolysis

A woman with a history of chronic idiopathic constipation and remote eating disorders presented to our hospital with generalised weakness and confusion due to severe hypokalaemic rhabdomyolysis. Her initial ECG showed down-sloping ST segment elevations consistent with the 'shark fin' sign, and initial echocardiography was consistent with Takotsubo cardiomyopathy (TCM). She later developed hypotension, hypoxaemia and low central venous oxygen saturation consistent with cardiogenic shock. A repeat ECG demonstrated the 'spiked helmet' sign, and repeat echocardiography showed new global hypokinesis. She was successfully supported with dobutamine on recognition of her worsening cardiomyopathy. This case highlights how the combination of recognised triggers of TCM such as hypokalaemia and rhabdomyolysis may predispose patients to a more morbid cardiac course and how the severity of such triggers may also influence cardiac morbidity. We additionally highlight the prognostic significance of two ECG patterns associated with TCM.