Association between mitral annulus calcification and subtypes of heart failure rehospitalization

BACKGROUND: Mitral annulus calcification (MAC) has been associated with cardiovascular diseases, including heart failure (HF); however, the associations between MAC and both the category and etiology of HF have not been fully elucidated. The aim of this study was to investigate the relationship between MAC and three types of HF rehospitalization: HF with preserved ejection fraction (HFpEF), HF with mid-range EF (HFmrEF), and HF with reduced EF (HFrEF). METHODS: We enrolled consecutive patients undergoing echocardiography, who were admitted to our hospital for clinically indicated congestive HF between April 2014 and March 2018. Cox proportionalhazards models were used after adjusting for age, gender, and hypertension. RESULTS: Of 353 patients, 40 (11.3%) had MAC. With a median follow-up of 2.8 years, 100 (28%) patients were rehospitalized for congestive HF (HFpEF 40%, HFmrEF 16%, HFrEF 44%, respectively). According to the Kaplan-Meier method, the estimated incidence of HFpEF rehospitalization in the MAC group was significantly greater than that in the non-MAC group (p < 0.001) whereas the incidences of HFmrEF and HFrEF rehospitalization were comparable between the groups (p = 0.101 and p = 0.291, respectively). In a multivariate analysis, MAC remained significantly associated with HFpEF rehospitalization (hazard ratio: 3.379; 95% confidence interval: 1.651-6.597). At initial HF hospitalization, E/e' was significantly higher in the MAC group (both septum and lateral, p < 0.05), suggesting a possible relationship between MAC and left ventricular diastolic function. CONCLUSIONS: Mitral annulus calcification was associated with increased HFpEF rehospitalization and might be a cause of left ventricular diastolic dysfunction.