Proprotein convertase subtilisin/kexin type 9 levels and aortic valve calcification: A prospective, cross sectional study

OBJECTIVE To investigate the possible association between plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) and the incidence and severity of calcific aortic valve disease (CAVD). METHODS This prospective, cross sectional study involved patients with and without (controls) aortic valve calcification diagnosed by transthoracic echocardiography and dual source computed tomography (DSCT) scan. Aortic valves calcification scores were calculated from DSCT scans and patients were graded: grade 1, no calcification; grade 2, mildly calcified; grade 3, moderately calcified; grade 4, heavily calcified. Plasma PCSK9 levels were measured using an enzyme-linked immunosorbent assay. RESULTS Forty patients were grade 1 (controls), 32 were grade 2, 48 were grade 3 and 32 were grade 4. Plasma levels of PCSK9 were significantly different between the four groups and the highest value was observed in the patients with grade 2 calcification. Only low-density lipoprotein cholesterol and lipoprotein (Lp)(a) were associated with the severity of CAVD. Regression analysis showed that age, Lp(a) and PCSK9 were independent predictors of CAVD. CONCLUSION Data from this cross sectional study in a small sample of patients showed that plasma PCSK9 was correlated with the presence of CAVD but not its severity.