NEJM
November 11, 2023
Restrictive or Liberal Transfusion Strategy in Myocardial Infarction and Anemia
Mazen Kherallah
Summarized by:
PICO Framework:
Population: Patients with myocardial infarction and a hemoglobin level of less than 10 g per deciliter.
Intervention: Liberal transfusion strategy (hemoglobin cutoff for transfusion <10 g per deciliter).
Comparison: Restrictive transfusion strategy (hemoglobin cutoff for transfusion 7 or 8 g per deciliter).
Outcome: Primary outcome was a composite of myocardial infarction or death at 30 days.
Methods:
Design: Phase 3, interventional, randomized controlled trial.
Participants: 3504 patients with myocardial infarction and hemoglobin levels <10 g/dL.
Results:
Transfusion: Average number of red-cell units transfused was 0.7±1.6 in the restrictive group and 2.5±2.3 in the liberal group.
Hemoglobin Levels: The mean hemoglobin level was 1.3 to 1.6 g/dL lower in the restrictive group than in the liberal group on days 1 to 3 after randomization.
Primary Outcome: Occurred in 16.9% of patients in the restrictive group and 14.5% in the liberal group (risk ratio 1.15; 95% CI, 0.99 to 1.34; P=0.07).
Mortality: 9.9% in the restrictive group and 8.3% in the liberal group (risk ratio, 1.19; 95% CI, 0.96 to 1.47).
Myocardial Infarction: Occurred in 8.5% of the restrictive group and 7.2% of the liberal group (risk ratio, 1.19; 95% CI, 0.94 to 1.49).
Conclusions:
The liberal transfusion strategy did not significantly reduce the risk of recurrent myocardial infarction or death at 30 days compared to the restrictive strategy.
However, the potential harms associated with the restrictive transfusion strategy cannot be excluded.
Implications for Intensivists:
This study suggests that a liberal transfusion strategy in acute myocardial infarction patients with anemia does not confer a significant advantage in reducing the risk of myocardial infarction or death within 30 days.
The marginally higher rates of adverse outcomes in the restrictive group, although not statistically significant, warrant careful consideration in clinical decision-making.
Intensivists should weigh the risks and benefits of transfusion thresholds on an individual patient basis, taking into account other clinical factors.
More inclined to keep Hg level above 8 in acute mycardial infarction and acute coronary syndrome.