Relationships between mitral annular calcification and cardiovascular events: A meta-analysis.

ABSTRACT

BACKGROUND: Mitral annular calcification (MAC) is prevalent in the aging population, with recent renewed interest regarding its associations with cardiovascular risk factors, outcomes, and influence on valvular heart disease and interventions. This meta-analysis aimed to report the relationships between MAC and cardiovascular mortality and morbidity events. METHODS: Relevant studies were searched from PubMed, Cochrane, and Embase databases until November 30, 2019. Associations between MAC as a binary variable with death and cardiovascular events were pooled using random-effects models. The main outcomes of interest were all-cause and cardiovascular mortality, myocardial infarction, stroke, heart failure, atrial fibrillation, and procedural outcomes. RESULTS: Among 799 article abstracts and 122 full-text articles screened, 26 (16 prospective and 10 retrospective) studies totaling 35 070 subjects were analyzed. MAC was associated with higher all-cause death, hazard ratio (95% confidence interval) 1.76 (1.43-2.22), and cardiovascular mortality 1.85 (1.45-23.5). It also positively correlated with myocardial infarction 1.48 (1.22-1.79), stroke 1.51 (1.22-2.05), incidental heart failure 1.55 (1.30-1.84), atrial fibrillation 1.75 (1.43-2.15), and their composite, major adverse cardiovascular events (MACE). Finally, conversion to mitral valve replacement at time of cardiac surgery was more in patients with MAC than without MAC, with odds ratio (95% confidence interval) 2.82 (1.28-6.18). CONCLUSION: Mitral annular calcification was overall associated with higher rates of death, and both individual and composite cardiovascular events. The presence of increasingly encountered MAC has significant clinical implications for cardiovascular risk assessment and valvular interventions.