Acute quadriplegic myopathy with loss of thick (myosin) filaments following heart transplantation.

Acute quadriplegic myopathy with loss of thick (myosin) filaments (AQM-LTF) is an acute toxic myopathy observed in critically ill patients and is characterized by proximal or diffuse weakness of extremities and difficulty in weaning from mechanical ventilation. In recent years, this myopathy has been described in transplanted patients, although only 5 cases have been reported following heart transplantation. We present 3 new cases and review the previous literature. We conclude that the clinical picture and outcome of AQM-LTF in heart-transplanted patients do not differ from those observed in other critically ill patients (transplanted and non-transplanted). Therefore, because AQM-LTF is often clinically suspected muscle biopsy should be quickly performed to confirm the diagnosis so that physical therapy may begin as soon as possible.