Trends and outcomes of red blood cell transfusion in patients undergoing transcatheter aortic valve replacement in the United States

Objectives: To examine temporal trends, predictors, and outcomes of red blood cell (RBC) transfusion in patients undergoing transcatheter aortic valve replacement (TAVR) in the United States. Methods: We used the National Inpatient Sample databases to identify TAVR procedures performed between January 2012 and September 2015 in the United States. Patients were propensity matched (within the strata of overt and no bleeding) on the likelihood of receiving RBC transfusion, and in-hospital outcomes were compared between the 2 groups in the matched cohort. Results: Among 46,710 TAVR procedures performed during the study period, rates of RBC transfusion were 17.3% (95% confidence interval [CI], 16.1%-18.5%). RBC transfusion rates decreased significantly from 29.5% during the first quarter of 2012 to 10.8% during the third quarter of 2015 (P < .001). Older age, female sex, peripheral vascular disease, chronic kidney disease, anemia, coagulopathy, and fluid/electrolyte disorders were associated with increased odds, whereas elective admission, obesity, and endovascular access were associated with decreased odds of RBC transfusion. In the propensity-matched cohort (7995 pairs with and without RBC transfusion), RBC transfusion was associated with increased risk of in-hospital mortality, infection, and transient ischemic attack/stroke in patients without bleeding (odds ratio [OR](Mortality), 2.29; 95% CI, 1.31-4.02; ORInfection, 2.13; 95% CI, 1.03-4.39; ORTransient ischemic attack/Stroke, 3.36; 95% CI, 1.52-7.45), but not in those with overt bleeding (ORMortality, 1.10; 95% CI, 0.68-1.48; ORInfection, 0.80; 95% CI, 0.45-1.45; ORTransient ischemic attack/Stroke, 1.16; 95% CI, 0.74-1.85); P-interaction < .05 for all. Conclusions: RBC transfusion is associated with worse clinical outcomes in TAVR patients without bleeding, but not in those with overt bleeding. The utility and optimal threshold for RBC transfusion in TAVR patients, especially among those with overt bleeding, warrants further prospective investigation.