From the Guidelines
For patients with both coronary artery disease (CAD) and myelodysplastic syndrome (MDS), the recommended threshold for blood transfusion is generally a hemoglobin level of 8 g/dL or below, as supported by the most recent and highest quality study 1.
Key Considerations
- This threshold should be adjusted based on individual patient factors, particularly symptoms of anemia and cardiac status.
- Patients with active cardiac ischemia, acute coronary syndrome, or significant cardiac symptoms may benefit from a higher transfusion threshold of 9-10 g/dL to maintain adequate oxygen delivery to the myocardium.
- When administering transfusions, a single-unit approach is preferred, followed by clinical reassessment before additional units are given, as recommended by the American Association of Blood Banks 1.
Rationale
The rationale for this approach balances the risks of anemia (which can worsen cardiac ischemia in CAD patients) against the potential complications of transfusions, including iron overload, alloimmunization, and transfusion reactions, which are particularly concerning in MDS patients who often require chronic transfusion support 1.
Monitoring and Optimization
Regular monitoring of symptoms, hemoglobin levels, and cardiac status is essential for optimizing the transfusion strategy in these complex patients, as emphasized by the American College of Cardiology/American Heart Association task force on practice guidelines 1.
Evidence Summary
A restrictive transfusion strategy has been shown to lead to outcomes that are at least as good, if not better, than a liberal transfusion strategy in patients with acute coronary syndrome 1, and a meta-analysis of 10 studies found that transfusion versus no transfusion was associated with an increase in all-cause mortality and subsequent MI rate 1.
From the FDA Drug Label
Using ESAs to target a hemoglobin level of greater than 11 g/dL increases the risk of serious adverse cardiovascular reactions and has not been shown to provide additional benefit [see Clinical Studies (14.1)]. In controlled clinical trials of patients with CKD comparing higher hemoglobin targets (13 - 14 g/dL) to lower targets (9 - 11.3 g/dL), Epogen and other ESAs increased the risk of death, myocardial infarction, stroke, congestive heart failure, thrombosis of hemodialysis vascular access, and other thromboembolic events in the higher target groups Placebo group patients also received darbepoetin alfa when their hemoglobin levels were below 9 g/dL
The threshold for blood transfusion is not explicitly stated in the provided drug labels for patients with CAD and myelodysplastic syndrome. However, based on the information provided, it can be inferred that:
- Hemoglobin targets: The labels suggest that targeting a hemoglobin level of greater than 11 g/dL may increase the risk of serious adverse cardiovascular reactions.
- Transfusion threshold: Although not directly stated, the labels mention that placebo group patients received ESA treatment when their hemoglobin levels were below 9 g/dL, implying that a hemoglobin level below 9 g/dL may be a threshold for intervention, such as blood transfusion, in certain patient populations.
- Clinical decision: A conservative clinical decision would be to consider blood transfusion for patients with CAD and myelodysplastic syndrome when their hemoglobin level falls below 9 g/dL, taking into account individual patient factors and clinical judgment 2 3.
From the Research
Threshold for Blood Transfusion
The threshold for blood transfusion in patients with CAD and myelodysplastic syndrome is a topic of ongoing debate.
- According to a study published in 2018 4, the adequate transfusion threshold is still being debated, although solid evidence suggests reserving red blood cell transfusions for patients with Hb level <8 g/dL and considering it in selected cases with Hb levels of between 8 and 10 g/dL.
- Another study from 2021 5 suggests that aggressive transfusions (Hg < 10 g/dL) are not associated with improved outcomes in cardiovascular disease.
- It is essential to consider the individual patient's condition, including the severity of anemia, cardiovascular disease, and myelodysplastic syndrome, when determining the threshold for blood transfusion.
Management of Anemia
- A study from 2011 6 highlights the importance of managing anemia in patients with myelodysplastic syndromes to reduce the risk of cardiovascular disease.
- Darbepoetin alfa has been shown to be effective in improving anemia in patients with myelodysplastic syndromes, with erythroid response rates comparable to those obtained with recombinant human erythropoietin (rHuEPO) 7.
- However, the use of iron supplements and erythropoiesis-stimulating agents in the setting of acute coronary syndrome is not supported by evidence 4.
Considerations for Patients with CAD and Myelodysplastic Syndrome
- Patients with CAD and myelodysplastic syndrome are at increased risk of cardiovascular disease mortality, and anemia is a significant predictor of cardiovascular disease outcomes in these patients 8, 6.
- Clinicians should be aware of the potential risks and benefits of blood transfusions in these patients and consider individualized management strategies to optimize outcomes.