Avoidance of Blood Transfusion to Patients Suffering From Myocardial Injury and Severe Anemia Is Associated With Increased Long-Term Mortality: A Retrospective Cohort Analysis

Myocardial injury and anemia are common among patients in internal medicine departments. Nevertheless, the level of anemia in which blood should be given to these patients is ill defined. We conducted a retrospective, cohort analysis. A total of 209 patients hospitalized to internal medicine, with myocardial injury (troponin I > 0.2 mcg/L, not diagnosed as ACS, acute coronary syndrome) and anemia (Hb < 10 g/dL, without overt bleeding) were included. The overall in-hospital mortality rate was 20.7%. A total of 37 patients (17.8%) had severe anemia (Hb < 8 g/dL). A total of 73 patients (34.9%) were transfused. Severe anemia was not associated with increased long-term mortality in the whole cohort while survival of patients with severe anemia that were not transfused was significantly reduced compared to transfused patients (44% vs 80%; P = 0.03). Mortality rates were similar for all patients with Hb ≥ 8 g/dL, regardless of transfusion (54% vs 49%; P = 0.60). Consistently, lack of blood transfusion in patients with severe anemia was independently associated with a 2.27 (1.08–4.81) greater adjusted risk of all-cause mortality (P-value for interaction = 0.04), whereas it did not significantly increase in patients with Hb ≥ 8 g/dL. Avoidance of blood transfusion is associated with unfavorable outcomes among patients with myocardial injury and severe anemia.