Posterior Mitral Valve Annulus Vegetation in the Presence of Mitral Annulus Calcification: A Case Report

The evaluation of patients who present at the emergency department with fever and a history of cardiac valve replacement should be thorough, and the possibility of endocarditis must be high in the differential diagnosis. The modified Duke’s criteria are recommended for the diagnosis of endocarditis, and the role of positron emission tomography-computed tomography (PET-CT) scan is highlighted in the presence of bioprosthetic valves among the recent guidelines. Here, we describe a challenging case of endocarditis in a patient with severe mitral annulus calcification and bioprosthetic aortic valve replacement. Transesophageal echocardiography revealed an echogenic mass on the posterior mitral annulus, which was confirmed to be a vegetation on the PET-CT scan. Despite adequate antibiotic therapy and no indication for emergency cardiac surgery, in the fourth week of treatment, an embolic event in the ophthalmic artery occurred, and the patient was admitted for surgery. Intraoperatively, the presence of vegetation was confirmed. Because severe mitral annulus calcification may act as a nidus for infective endocarditis, special attention must be paid to these patients. Additional studies are required in patients with residual vegetation at the end of antibiotic treatment, especially if they have increased dimensions, to accurately formulate the optimal management plan.