Heavy Calcification of Left Atrium and Calcific Mass on Mitral Valve: An Unusual Presentation of Ankylosing Spondylitis.

Ankylosing spondylitis is a complex chronic disease that starts from the spine and sacroiliac joint, causes joint stiffness, and affects the quality of life. Aortic dilatation, aortic valve insufficiency, and heart block due to conduction system involvement are the leading accompanying cardiac pathologies. In this case report, we aimed to show a rare cardiac involvement of left atrial calcification, pericardial involvement, and formation of a calcified inflammatory mass that might be misdiagnosed as vegetation on the mitral valve in a late-stage ankylosing spondylitis patient, by using multimodality imaging and histopathological diagnosis.