Presence and impact of anemia in patients supported with left ventricular assist devices

Abstract

Data on anemia and its effects on patients supported with continuous-flow left ventricular assist devices (LVADs) are lacking. This study sought to describe the presence of anemia over time and investigate its association with mortality, quality of life, exercise capacity, and adverse events in LVAD patients. Adults receiving durable LVADs between 2008 and 2017 were identified from the INTERMACS database. The full cohort was stratified according to anemia severity (no anemia, mild, and moderate-severe). The analysis of 19,509 patients (females: 21.2%, age: 56.9±12.9 years) showed that moderate-severe anemia affected 45.2% of patients at baseline, 33.5% of them at 6 months, and 32.3% in the fourth year after implantation. The presence of normal hemoglobin was 24.4% before surgery, 32.5% at 6 months, and 36.6% at 4 years after implantation. Multivariable linear mixed-effect regression revealed that the average hemoglobin over time was significantly lower (β, -0.233, 95% confidence interval (CI): -0.282 to -0.185), and the reduction of hemoglobin over time was bigger (β, -0.032 95% CI: -0.035 to -0.028) for LVAD nonsurvivors compared with LVAD survivors. Adjusted Cox regression showed that the severity of preimplant anemia was associated with higher mortality (HR, mild: 1.19; 95%CI: 1.05-1.35 and moderate-severe: 1.44; 95% CI: 1.28-1.62), with similar results in competing risk regression. Anemia progression during follow-up was associated with decreased Kansas City Cardiomyopathy Questionnaire scores and shorter 6-minute walk distances. In patients supported with LVADs, anemia is a frequent comorbidity, and deterioration over time is associated with poor prognosis.