The Los Angeles County Department of Public Health (Public Health) has identified three confirmed cases and one suspected case of a non-tuberculous mycobacterial infection, Mycobacterium chimaera, all of which occurred in persons with a history of open-chest cardiac surgery. M. chimaera are slow-growing mycobacteria which can cause infections that occur most often at the surgical site but may not become apparent until months or years after surgery.

Public domain image via Pixabay
Public domain image via Pixabay

Published findings have linked post-surgical M. chimaera infection with exposure to a specific brand of heater- cooler device, LivaNova (formerly Sorin Stockert) 3T, used during surgery. As of October 2016, more than 70 cases have been identified worldwide. More than 250,000 heart bypass procedures using heater-cooler devices are performed in the United States every year and approximately 60% used the devices that have been associated with these infections. The risk that patients will develop an infection following exposure to a contaminated device is very low, including at hospitals where a previous infection has been identified.

In October 2016, the Centers for Disease Control and Prevention (CDC) issued a health alert, which Public Health forwarded to all LA County facilities, describing the risk of M. chimaera infections associated with the use of these heater-cooler devices during open-chest cardiac surgery and making recommendations for surveillance, patient notification, and prevention. In November 2016, the CDC, the U.S. Food and Drug Administration, and the California Department of Public Health provided additional information to health facilities.

Public Health has been working with the hospitals that have identified cases to increase surveillance and implement control measures. Public Health also has been communicating with all hospitals in Los Angeles County that have used these devices to assess compliance with CDC recommendations.