Transfusing more blood may benefit MI patients with anemia

A large percentage of patients had suffered a previous heart attack, heart failure, diabetes or kidney disease. The average age of participants was 72, with 45 percent being women.

The MINT trial evaluated two transfusion strategies in more than 3,500 enrolled participants at 144 hospitals in six countries. Half of the participants in the study were given more blood to keep their blood count greater than 10 grams per deciliter (g/dL), considered a liberal transfusion strategy. Half didn’t receive blood unless their blood count was less than eight g/dL, the restrictive transfusion strategy. All patients in the study had a heart attack and anemia, meaning they had a hemoglobin blood count of less than 10 g/dL. A normal blood count is 12 to 13 g/dL.

The researchers compared the frequency of the main outcome of death or recurrent heart attack at 30 days after enrollment into the trial. Although not statistically significant, the study found the frequency of mortality or recurrent heart attack was 2.4 percent lower when a liberal approach was used.

Carson and the study team stress that further clinical trials, meta-analyses of studies and additional analysis of the MINT trial data are critical to ensuring physicians are informed with the best evidence when considering when to transfuse patients who had a heart attack and have anemia.

Reference: Jeffrey L. Carson, Maria Mori Brooks, Paul C. Hébert, Shaun G. Goodman, Marnie Bertolet, Simone A. Glynn, Bernard R. Chaitman, Tabassome Simon, Renato D. Lopes, Andrew M. Goldsweig, Andrew P. DeFilippis, J. Dawn Abbott, Restrictive or Liberal Transfusion Strategy in Myocardial Infarction and Anemia, DOI: 10.1056/NEJMoa2307983.