Mitral Annular Calcification and Coronary Artery Disease: Associations and Prognostic Implications: An Up-to-Date Review

Mitral annular calcification (MAC) is a common, degenerative calcific process of the mitral valve annulus readily identified on echocardiography and classifiable by extent as mild, moderate, or severe. Epidemiologic and registry data link MAC to older age, metabolic risk factors, female sex, and markers of cardiac remodeling. MAC is associated with impaired coronary microvascular function, suggesting endothelial dysfunction as a mechanistic bridge to coronary artery disease (CAD). Multiple imaging- and angiography-based studies report a consistent association between MAC and prevalent, severe, or multivessel obstructive CAD across diverse populations, including older adults, younger patients undergoing simultaneous echocardiography and angiography, patients with dilated cardiomyopathy, and those with end-stage renal disease or on dialysis. Some cohorts find that MAC independently predicts myocardial ischemia and adverse cardiovascular events. Computed tomography studies generally corroborate a link between MAC and coronary calcification and plaque burden, and the combined presence of MAC and aortic valve calcification denotes a particularly high-risk coronary phenotype with more calcified/mixed and potentially vulnerable plaques. However, studies show that the crude association between MAC and CAD is attenuated after adjustment for age and other confounders, and some analyses find no independent relation to angiographic severity or complexity. Overall, MAC appears to be a useful adjunctive marker of systemic atherosclerosis and higher coronary risk rather than definitive proof of obstructive CAD; its presence on imaging should prompt consideration of further coronary evaluation in appropriate clinical contexts.