THE ESSENTIAL
- According to a team of researchers, it would be “logical” to be able to treat patients with both a myocardial infarction and anemia by transfusing them with more blood.
- The new study compared the effect of two transfusion strategies, restrictive (giving less blood) and liberal (giving more blood), over six months in more than 3,500 patients with myocardial infarction and anemia.
- As a result, among other things, the risk of death from cardiac causes was reduced by 52% in the liberal group compared to the restrictive group (6% versus 9%).
Myocardial infarction, also called heart attack, is one of the leading causes of death in the world, including in France with around 100,000 cases per year. Double punishment for patients who have suffered a heart attack, they often also suffer from anemia, a lack of red blood cells in the blood. This can worsen their condition because “The lower the level of hemoglobin (the protein that carries oxygen in the blood), the greater the risk of cardiovascular complications.”
That’s why, according to a new study published in the journal Traffic and recently presented at the European Society of Cardiology (ESC) congress in London, it would be “logic” to be able to treat patients with both myocardial infarction and anemia by transfusing them with more blood.
The question of blood transfusion in case of myocardial infarction and anemia
“The benefit of transfusion in this context of myocardial infarction is nevertheless debated”according to a statement from the French researchers who participated in the work. In theory, the transfusion should increase the supply of oxygen to the myocardium, but recent data have revealed that if “Transfused blood has a high capacity to capture oxygen, it has difficulty releasing it into the body’s tissues, especially into the heart damaged by a heart attack”. In addition, during their storage before being transfused, red blood cells rapidly lose their nitric oxide, a substance that helps blood vessels function properly, which can be a problem in patients with fragile hearts.
“Very few randomized trials have analyzed the impact of different transfusion strategies” for patients with both a heart attack and anemia”scientists point out. And the few trials that have been conducted in the United States and Europe – on 45, 110 or even 660 patients – have produced results that are either “opposites”, either “which did not allow a clear conclusion”.
Heart risk cut in half with blood transfusion
The new study, carried out in 144 centres in the United States, Canada, Brazil, Australia and France (AP-HP), compared the effect of two transfusion strategies, restrictive (giving less blood) and liberal (giving more blood), over a six-month period in more than 3,500 patients suffering from myocardial infarction and anaemia. “This is, by far, the largest trial ever conducted in this indication.”
The analysis found that after one month, there were fewer deaths or heart attacks in the group that received more blood transfusions (14.5% of cases) compared with the group that received fewer (16.9%). As for overall mortality at six months, it was lower (20.5% of cases) in the group that received the most transfusions than in the group that received the least (21.7%). “More interestingly, the risk of death from cardiac causes would be reduced by 52% in the liberal group compared to the restrictive group (6% versus 9%).”
The scientists’ conclusive conclusion: “All of these results converge towards a benefit of a ‘liberal’ transfusion strategy compared to a ‘restrictive’ strategy: transfusing more blood to patients with myocardial infarction and anaemia would improve their chances of survival.”
