Mitral Annular Calcification Related Infective Endocarditis: A Contemporary Systematic Review

Mitral annular calcification (MAC) is a chronic degenerative process often found incidentally on imaging. MAC is associated with elevated risk of atherosclerosis and stroke. The association between MAC and the risk of infective endocarditis (IE) is less well known. Therefore, we conducted this systematic review in order to understand the diagnosis, clinical outcomes, and management of IE associated with MAC. We conducted a systematic review of published data regarding MAC related IE in various databases until November 20, 2019. Case series and cohort studies were included. A total of 8 studies with a cohort of 113 patients were included. Mean age was 69 years with equal gender distribution (50% female). Hypertension (55.8%) was the most common comorbidity seen in this patient population. IE was diagnosed by either antemortem trans esophageal echocardiographic examination (76%) or post-mortem autopsy (24%). Staphylococcus aureus (47%) was the most common pathogen identified. MAC was adjudicated to be moderate-to-severe in 100% of identified cases, with 77.9% of cases presenting with distinct vegetation's. Twenty-six percent of patients (n = 29) underwent surgery. MAC may be associated with development of IE. Echocardiography is the most common non-invasive technique for diagnosis. Due to the difficulties associated with antemortem diagnosis, diagnosis is occasionally made on post-mortem examination. Neurologic complications are frequently encountered, and reported mortality is high in MAC associated IE.