Myocardial Ischemia and Transfusion

In most clinical settings, evidence suggests it is safe to wait to give a blood transfusion. However, for those who have suffered a heart attack, there is a lack of high quality evidence to guide transfusions. This 3500 subject multi-center randomized trial will fill that void.

Hospital inpatients diagnosed with myocardial infarction who have blood counts less than 10 g/dL are randomized to receive either a liberal or a restrictive transfusion strategy.

Patients randomized to the liberal transfusion strategy will receive a red blood cell transfusion anytime there is a blood count of less than 10 g/dL.

Patients randomized to the restrictive transfusion strategy are permitted to receive a blood transfusion if the blood count is below 8 g/dL and the physician believes it is in the patient's best interest. A transfusion will be strongly recommended if the blood count drops to less than 7 g/dL. If the patient has symptoms of angina (e.g., chest discomfort described as pressure or heaviness) that do not go away with medication, a blood transfusion is ordered regardless of the blood count.

The transfusions strategies will be maintained until hospital discharge for a maximum of 30 days.

Patients will be followed for 30 days for clinically relevant outcomes. Vital status will be confirmed at 180 days.

Inclusion criteria

• 18 years of age or older
• Either ST segment elevation myocardial infarction or Non ST segment elevation myocardial infarction consistent with the 3rd Universal Definition of Myocardial Infarction criteria that occurs on admission or during the index hospitalization
• Hemoglobin concentration less than 10 g/dL at the time of random allocation
• Patient physician believes that both of the transfusion strategies are consistent with good medical care for the patient

Exclusion criteria

• Uncontrolled acute bleeding at the time of randomization defined as the need for uncrossed or non-type specific blood
• Decline blood transfusion
• Scheduled for cardiac surgery during the current admission
• Receiving only palliative treatment
• Known that follow-up will not be possible at 30 days
• Previously participated in MINT
• Currently enrolled in a competing study that interferes with the intervention or follow-up of MINT or enrolled in a competing study that has not been approved by the local Institutional Review Board
• Patient physician does not believe the patient is an appropriate candidate for the trial