Gas gangrene (also known as clostridial myonecrosis and myonecrosis) is a bacterial infection that produces gas in tissues in gangrene. This deadly form of gangrene usually is caused by Clostridium perfringens bacteria.It is a medical emergency. Myonecrosis is a condition of necrotic damage, specific to muscle tissue.his deadly form of gangrene usually is caused by Clostridium perfringens bacteria. It is a medical emergency. Myonecrosis is a condition of necrotic damage, specific to muscle tissue.