Anemia is associated with higher mortality and morbidity after thoracic endovascular aortic repair.

BACKGROUND

It is uncertain whether preoperative anemia is independently associated with thoracic endovascular aortic repair (TEVAR) outcomes. Using a national vascular surgery database, we evaluated the associations between preoperative anemia and 30-day mortality, postoperative complications, and 1-year survival for patients undergoing TEVAR.

METHODS

We retrospectively analyzed all patients in the Vascular Quality Initiative who had undergone TEVAR for aortic dissection, aortic aneurysm, penetrating aortic ulcer, hematoma, or thrombus between January 2011 and December 2019. We excluded patients with a ruptured aneurysm, traumatic dissection, emergent repair, treated aorta distal to zone 5, polycythemia, transfusion of >4 U of packed red blood cells intraoperatively or postoperatively, and missing data on hemoglobin level or surgical indications. The final study cohort was dichotomized into two groups: normal/mild anemia (women, ≥10 g/dL; men, ≥12 g/dL) and moderate/severe anemia (women, <10 g/dL; male, <12 g/dL). Propensity scores by stratification were used to control for confounding in the analysis of the association between the outcomes of 30-day mortality, postoperative complications, and 1-year survival and a binary indicator variable of moderate/severe anemia vs normal/mild anemia. Kaplan-Meier analysis and log-rank tests were used to compare the 1-year survival between the two groups. A Cox regression model was fitted to assess the associations between anemia and survival outcomes.

RESULTS

A total of 3391 patients were analyzed, 958 (28.3%) of whom had had moderate/severe anemia. After adjustment for multiple clinical factors using propensity score stratification, moderate/severe anemia was associated with a 141% increased odds of 30-day mortality (adjusted odds ratio [aOR], 2.41; 95% confidence interval [CI], 1.15-5.05; P = .019), 58% increased odds of any in-hospital complication (aOR, 1.58; 95% CI, 1.17-2.13; P = .003), 281% increased odds of intraoperative transfusion (aOR, 3.81; 95% CI, 2.68-5.53; P < .001). In addition, moderate/severe anemia was associated with significantly worse survival within the first year after TEVAR (log-rank P < .001; 1-year survival rate using Kaplan-Meier estimates, 86.4% ± 1.3% standard error vs 92.5% ± 0.6% standard error) and with an increased risk of mortality in the first postoperative year (adjusted hazard ratio, 1.81; 95% CI, 1.16-2.82; P = .009).

CONCLUSIONS

We found that moderate or severe anemia is associated with significantly increased odds of mortality, postoperative complications, and worse 1-year survival after TEVAR. Future studies are needed to evaluate the effect of anemia correction on the outcomes of TEVAR.