Invasive cardiovascular infection by Mycobacterium chimaera potentially associated with heater-cooler units used during cardiac surgery, 30 April 2015

Risk assessment

​Since 2011, cases of infection caused by Mycobacterium chimaera have been detected in patients having previously undergone cardiac surgery in Europe.
Healthcare providers involved in caring for patients who have undergone open-heart surgery should be vigilant for cases of endocarditis or other cardiovascular infection of unidentified origin and consider testing specifically for slow-growing non-tuberculous mycobacteria such as M. chimaera.

Regulatory bodies in charge of licensing and agencies monitoring the safety of such devices should be aware of the potential association of invasive cardiovascular infections caused by M. chimaera with heater-cooler units and relevant information should be disseminated to all centres performing cardiac surgery.

ECDC is maintaining vigilance for additional information that can be used to further evaluate the public health risk of invasive cardiovascular infection by M. chimaera associated with heater-cooler units and will update its risk assessment as new evidence is obtained.

Executive Summary

The investigation in Switzerland identified M. chimaera contamination in heater-cooler units – used to regulate the temperature of the blood during extracorporeal circulation – as the potential source of infection. Some strains from air and water samples showed matching Random Amplified Polymorphic DNA (RAPD)-PCR patterns. This suggests M. chimaera-contaminated heater-cooler units as a potential source of infection. Switzerland has reported six M. chimaera infections, two of which were associated with a fatal outcome of whom two patients have died. The Netherlands has reported one fatal M. chimaera infection in a patient following cardiac surgery. A case has also been reported in Germany. Healthcare providers involved in caring for patients who have undergone open-heart surgery should be vigilant for cases of endocarditis or other cardiovascular infection of unidentified origin and consider testing specifically for slow-growing non-tuberculous mycobacteria such as M. chimaera.  Regulatory bodies in charge of licensing and agencies monitoring the safety of such devices should be aware of the potential association of invasive cardiovascular infections caused by M. chimaera with heater-cooler units and relevant information should be disseminated to all centres performing cardiac surgery. ECDC is maintaining vigilance for additional information that can be used to further evaluate the public health risk of invasive cardiovascular infection by M. chimaera associated with heater-cooler units.