Relationship between cardiac calcification and left ventricular hypertrophy in patients with chronic kidney disease at hemodialysis initiation
BACKGROUND Vascular and valvular calcifications are a common finding in chronic kidney disease (CKD) patients and are associated with increased morbidity and mortality. We investigated the hypothesis that calcification of the cardiac valves is a marker of coronary artery calcification (CAC) and thoracic aorta calcification (AoC) in hemodialysis (CKD-5) patients. METHODS This was a cross-sectional study of 145 maintenance CKD stage 5 (CKD-5) patients. All patients underwent electron beam tomography for quantification of CAC and AoC score via the Agatston score. The presence of calcification of the cardiac valves was assessed by standard bi-dimensional echocardiography. RESULTS Eighty-four of the study patients (58%) had echocardiographic evidence of valvular calcification. A significant and graded association between valvular calcification and CAC as well as AoC was detected. Patients with 1 or 2 calcified valves had a significantly greater likelihood of having a CAC score >1,000 (odds ratio [OR] = 5.94; 95% confidence interval [95% CI], 1.91-18.44; p=0.002; and OR=3.27; 95%CI, 1.36-7.88; p=0.007, respectively). Similarly, the presence of 1 or 2 calcified valves was associated with an eightfold and threefold increased probability of an AoC score greater than the third quartile, respectively. CONCLUSIONS This cross-sectional analysis shows that calcification of the cardiac valves is closely associated with vascular calcification, an established marker of risk in prevalent hemodialysis patients.