A recent study by Sommerstein and colleagues¹ has demonstrated a causal link between Mycobacterium chimaera infection and the LivaNova PLC Stöckert 3T heater-cooler system (LivaNova PLC, London, United Kingdom) used in cardiac surgery. The heater-cooler unit disrupts laminar air flow and enables airborne spread of M chimaera from a contaminated unit to a surgical site. M chimaera infection may not manifest immediately, and infections occurring up to 4 years after cardiac surgery have been reported.2, 3 These cases are rare, and the largest series from a single institution includes 6 patients over an experience of 3700 operations during a 4-year period (a cross-sectional prevalence of 0.16%).² Nevertheless, M chimaera infection can cause serious complications, including prosthetic valve endocarditis, aortic graft infection, and myocarditis.² The initial diagnostic workup of a patient with suspected M chimaera infection consists of acid-fast bacilli smear and culture. Definitive diagnosis may require more specific tests such as the BACTEC Myco/F Lytic culture vial (Becton, Dickinson and Company, Franklin Lakes, NJ) for blood culture, which does not yield prompt results and is not widely available. There is no consensus regarding optimal antimicrobial therapy, and combinations of clarithromycin, rifabutin, ethambutol, and amikacin have been used.² Mortality from M chimaera infection is high, which is mainly due to nonspecific presentation and late diagnosis, as well as the challenging nature of finding adequate antimicrobial therapy.