Progression of Coronary Artery Calcium Density and Major Adverse Cardiovascular Events

Background And Aims: We aimed to investigate the relationship between coronary artery calcium (CAC) density progression and major adverse cardiovascular events (MACE), and the prognostic value of CAC density progression.

Methods: Patients with serial CAC scans were enrolled in this study. CAC density was directly measured in calcified lesions. Change and rate of progression of CAC density were calculated. Cox proportional hazard regression was utilized to estimate hazard ratios (HRs) for time to MACE regarding CAC density. The incremental prognostic value and the reclassification ability of CAC density progression were evaluated using the C-index and continuous net reclassification index (NRI).

Results: 304 patients (57.86 ± 9.47 years, 69.4 % male) were included. There were 47 MACE over a follow-up period of 76.00 (56.00-95.00) months. After adjustment for risk factors and CAC volume, the change of CAC density was inversely associated with MACE (per 10HU: HR: 0.956, 95 % confidence interval: 0.920-0.992, p = 0.018). Adding the change of CAC density to risk factors and baseline CAC density improved the C-index (0.694 vs. 0.678, p = 0.026). Adding the change of CAC density improved reclassification of MACE compared with risk factors and baseline CAC density [NRI = 0.432 (0.016-0.789)].

Conclusions: CAC density progression is inversely associated with MACE. The addition of the change of CAC density improves prognostic value compared to baseline risk factors and CAC density and optimizes risk reclassification.