Relation of Aortic Valve and Coronary Artery Calcium in Patients With Chronic Kidney Disease to the Stage and Etiology of the Renal Disease

Abstract

Patients with chronic renal failure have increased cardiac calcium loads. Previous studies have investigated the prevalence and quantitative extent of aortic valve calcium (AVC) and coronary artery calcium (CAC) in patients with various stages of chronic kidney disease (CKD). However, the impact of preexisting atherosclerosis on the calcification burden has not been clarified. Therefore, this study was conducted to examine the effect of CKD stage as well as the primary cause of renal failure (atherosclerotic vs nonatherosclerotic) on AVC and CAC. Twenty-two, 13, and 28 patients with stage 3, 4, and 5 CKD, respectively, were included, of whom 24 had atherosclerotic CKD. Patients underwent electron-beam computed tomography to assess AVC and CAC. AVC was present in 27% of patients with stage 3 CKD, in 38% of patients with stage 4 CKD, and in 43% of patients with stage 5 CKD. CAC was present in 77% of patients with stage 3 CKD, in 54% of patients with stage 4 CKD, and in 64% of patients with stage 5 CKD. There was no correlation between CKD stage and the quantitative extent of AVC and CAC. AVC was more frequent (58% vs 23%, p <0.01) and more extensive (median score 43 [range 0 to 494] vs 0 [range 0 to 8], p <0.01) in patients with CKD caused by atherosclerotic renal disease than in patients with nonatherosclerotic causes of CKD. CAC was more frequent (83% vs 56%, p <0.05) and more extensive (median score 437 [range 61 to 1,565] vs 31 [range 0 to 155], p <0.001) in patients with atherosclerotic causes of CKD than in patients with CKD caused by nonatherosclerotic renal disease. In conclusion, the prevalence as well as the severity of AVC and CAC did not vary between patients with stage 3, 4, and 5 CKD. Cardiac calcification, both AVC and CAC, were more frequent and more severe in patients with atherosclerotic causes of renal failure. These results suggest that cardiac calcium is related to atherosclerotic burden rather than to the severity of CKD.