Does chronic kidney disease affect the diagnostic accuracy of aortic valve calcium scoring for severe aortic stenosis?
While aortic valve calcium scoring remains sensitive for ruling out severe aortic stenosis in patients with chronic kidney disease, its specificity significantly declines with worsening renal function, increasing the risk of false positives.
BACKGROUND Aortic valve calcium scoring (AVCS) via noncontrast Computed Tomography (CT) has emerged as a valuable adjunct to echocardiography in diagnosing aortic stenosis (AS). However, its diagnostic accuracy in patients with chronic kidney disease (CKD) -a population characterized by extensive extra-valvular calcification- remains unclear. METHODS This retrospective multicenter study included 2909 adults who underwent AVCS and echocardiography between 2015 and 2025 across Mayo Clinic sites. Patients were stratified by glomerular filtration rate (eGFR) to assess AVCS diagnostic performance for severe AS in CKD vs non-CKD cohorts. Receiver operating characteristic (ROC) curves, stratified by sex and eGFR categories, were used to evaluate diagnostic accuracy. Optimal thresholds were derived using Youden's index and compared with guideline-recommended cutoffs. RESULTS AVCS demonstrated high diagnostic accuracy in patients with preserved renal function (AUC 0.861), but performance declined with worsening CKD. AUC dropped to 0.791 (eGFR <60), 0.727 (eGFR <45), and 0.691 (eGFR <30). Specificity declined significantly across worsening eGFR, despite stable sensitivity. Sex-stratified analysis revealed similar results. CONCLUSION AVCS remains a reliable tool to rule out severe AS in patients with CKD, but declining specificity with worsening kidney function -likely due to nonvalvular calcification- highlights the risk of false positives. In CKD populations, AVCS thresholds should be interpreted cautiously and integrated with multimodal evaluation and clinical data.
Sheashaa et al. (Tue,) studied this question.