Severe Aortic Stenosis and Chronic Kidney Disease: Outcomes and Impact of Aortic Valve Replacement

Background The prognostic significance of chronic kidney disease (CKD) in severe aortic stenosis is poorly understood and no studies have yet evaluated the effect of aortic-valve replacement (AVR) versus conservative management on long-term mortality by stage of CKD. Methods and Results We included 4119 patients with severe aortic stenosis. The population was divided into 4 groups according to the baseline estimated glomerular filtration rate: no CKD, mild CKD, moderate CKD, and severe CKD. The 5-year survival rate was 71±1% for patients without CKD, 62±2% for those with mild CKD, 54±3% for those with moderate CKD, and 34±4% for those with severe CKD (P<0.001). By multivariable analysis, patients with moderate or severe CKD had a significantly higher risk of all-cause (hazard ratio [HR] [95% CI]=1.36 [1.08-1.71]; P=0.009 and HR [95% CI]=2.16 [1.67-2.79]; P<0.001, respectively) and cardiovascular mortality (HR [95% CI]=1.39 [1.03-1.88]; P=0.031 and HR [95% CI]=1.69 [1.18-2.41]; P=0.004, respectively) than patients without CKD. Despite more symptoms, AVR was less frequent in moderate (P=0.002) and severe CKD (P<0.001). AVR was associated with a marked reduction in all-cause and cardiovascular mortality versus conservative management for each CKD group (all P<0.001). The joint-test showed no interaction between AVR and CKD stages (P=0.676) indicating a nondifferentialeffect of AVR across stages of CKD. After propensity matching, AVR was still associated with substantially better survival for each CKD stage relative to conservative management (all P<0.0017). Conclusions In severe aortic stenosis, moderate and severe CKD are associated with increased mortality and decreased referral to AVR. AVR markedly reduces all-cause and cardiovascular mortality, regardless of the CKD stage. Therefore, CKD should not discourage physicians from considering AVR.