Clinical outcomes with use of erythropoiesis stimulating agents in patients with the heart mate II left ventricular assist device

Objectives: This study evaluated clinical outcomes associated with erythropoiesis stimulating agent (ESA) use in left ventricular assist devices (LVAD)-supported patients. Background: Use of ESAs in patients with LVADs may minimize blood transfusions and decrease allosensitization. ESAs increase thrombotic events, which is concerning because LVADs are sensitive to pump thrombosis (PT). Methods: We retrospectively reviewed 221 patients at our center who received a HeartMate II (Thoratec Corp., Pleasanton, California) LVAD between January 1, 2009 and June 6, 2013. Patients were divided into those who received ESAs during index admission (n= 121) and those who did not (n= 100). Suspected PT was defined as evidence of thrombus in the LVAD or severe hemolysis (lactate dehydrogenase >1,000 mg/dl or plasma-free hemoglobin >40 mg/dl). Outcomes were compared between cohorts using inverse probability-weighted analyses. Results: During a mean follow-up of 14.2 ± 11.9 months, suspected PT occurred in 37 patients (ESA 23%, no ESA 12%; p=0.03). The ESA cohort received ESAs 13.9 ± 60.9 days after LVAD implantation. At 180 days, event-free rates for suspected PT were ESA 78.6% versus no ESA 94.5% (p< 0.001). ESA use had higher rates of suspected PT (hazard ratio [HR]: 2.35; 95% confidence interval [CI]: 1.38 to 4.00; p= 0.002). For every 100-unit increase in cumulative ESA dosage, the hazard of suspected PT increased by 10% (HR: 1.10; 95% CI: 1.04 to 1.16; p< 0.001). After inverse probability weighting, ESA use was associated with a significantly higher rate of all-cause mortality (HR: 1.62; 95% CI: 1.12 to 2.33; p= 0.01). Conclusions: ESA use in LVAD patients is associated with higher rates of suspected PT.