Abstract 15314: Advanced Cardiovascular Imaging for the Diagnosis of Mycobacterium Chimaera Prosthetic Valve Infective Endocarditis After Open-Heart Surgery: A Systematic Review

Abstract

Introduction: Mycobacterium chimaera is an emerging pathogen, recognized to cause prosthetic valve infective endocarditis (PVIE) and disseminated infection following open-chest cardiac surgery with certain contaminated heater-cooler systems. Diagnosis is challenging and requires a very high index of suspicion. Data regarding the optimal cardiac imaging evaluation of this condition is limited. Methods: Scopus, PubMed, EMBASE, Ovid and Cochrane were searched for published articles through October 2021, using keywords “Mycobacterium chimaera”, “Prosthetic valve” and “Endocarditis”. 169 articles were found and reviewed for study eligibility. Articles were included if they consisted of Mycobacterium chimaera causing IE, with imaging modalities used to establish diagnosis Results: Thirty-three articles were included, yielding twenty-two cases of Mycobacterium chimaera PVIE. The disease manifested on average thirty months after surgery, with an average patient age of 59 years (90% male). Imaging modalities to establish the diagnosis of prosthetic valve infective endocarditis included: transthoracic echocardiogram in 5 cases, transesophageal echocardiogram (TEE) in nine cases, 18F-FDG-PET/CT in seven cases. A combination of imaging modalities with TEE and 18F-FDG-PET/CT was reported once; TTE, TEE and 18F-FDG-PET/CT was also noted in one case. Lastly there was one instance each of combined use of TTE, TEE, and one of the following: CTA, Cardiac MRI, or standard CT. Nine cases did not specify the imaging modality used to achieve diagnosis. Ten patients died. Conclusions: PVIE due to Mycobacterium chimaera infection is a rare and challenging diagnosis, which requires a high index of suspicion. Accurate diagnosis should be aided by multimodality cardiac imaging, with 18F-FDG-PET/CT being a powerful adjunct imaging modality.