Anemia in Patients with Severe Aortic Stenosis

Abstract

Prognostic impact of anemia complicating severe aortic stenosis (AS) remains unclear. We assessed the impact of anemia on cardiovascular and bleeding outcomes in 3403 patients enrolled in the CURRENT AS registry. 835 patients (25%) had mild (hemoglobin 11.0-12.9 g/dl for men/11.0-11.9 g/dl for women) and 1282 patients (38%) had moderate/severe anemia (Hb ≤ 10.9 g/dl) at diagnosis of severe AS. Mild and moderate/severe anemia were associated with significantly increased risks relative to no anemia (hemoglobin ≥13.0 g/dl for men/≥12.0 g/dl for women) for the primary outcome measure (aortic valve-related death or heart failure hospitalization) in the entire population [hazard ratio (HR): 1.30; 95% confidence interval (CI): 1.07-1.57 and HR: 1.56; 95%CI: 1.31-1.87, respectively] and in the conservative management stratum (HR: 1.73; 95%CI: 1.40-2.13 and HR: 2.05; 95%CI: 1.69-2.47, respectively). Even in the initial aortic valve replacement stratum, moderate/severe anemia was associated with significantly increased risk for the primary outcome measure (HR: 2.12; 95%CI: 1.44-3.11). Moreover, moderate/severe anemia was associated with significantly increased risk for major bleeding while under conservative management (HR: 1.93; 95%CI: 1.21-3.06). These results warrant further study to explore whether better management of anemia would lead to improvement of clinical outcomes.

Figure 1

(A) Histograms of hemoglobin levels. (B) Study flowchart AS = aortic stenosis, AVR = aortic valve replacement.

Figure 2

Kaplan–Meier curves for the primary outcome measure according to the severity of anemia. (A) Entire cohort. (B) Conservative stratum. (C) Initial AVR stratum. The primary outcome measure was defined as a composite of aortic valve-related death of heart failure hospitalization. Severity of anemia was classified as no anemia (Hb ≥ 13.0 g/dl for men, and≥12.0 g/dl for women), mild anemia (Hb 11.0–12.9 g/dl for men, and 11.0–11.9 g/dl for women), and moderate/severe anemia (Hb ≤ 10.9 g/dl). AVR = aortic valve replacement, and Hb = hemoglobin.

Figure 3

Relationship between anemia and bleeding events under conservative management. (A) Kaplan–Meier curves for major or life-threatening bleeding events under conservative management in the entire cohort. (B,C) Sites (B) and severity (C) of bleeding under conservative management in the entire cohort of bleeding. Cumulative incidence of major or life-threatening/disabling bleeding events under conservative management was estimated by the Kaplan-Meier method with censoring at AVR/TAVI. AVR = aortic valve replacement, BARC = Bleeding Academic Research Consortium, and TAVI = transcatheter aortic valve implantation.