Myocardial Ischemia and Transfusion Pilot

Inclusion Criteria: * age 18 or older; * STEMI (ST segment elevated myocardial infarction) * NSTEMI (Non ST segment elevation myocardial infarction) * unstable angina * stable coronary artery disease (undergoing cardiac catheterization during the index hospitalization); * written informed consent has been obtained * hemoglobin concentration less than 10 g/dL at the time of random allocation. Exclusion Criteria: * bleeding cannot be controlled at the cardiac catheterization puncture site and/or require surgery to repair vessel * retroperitoneal bleeding requiring surgery * clinically important hemodynamic instability based on the judgment of the treating physician * terminal malignancy or life expectancy less than 6 months * scheduled for cardiac surgery within the next 30 days * symptomatic at the time of randomization * declines blood transfusion * history of a clinically significant transfusion reaction * inability to provide informed consent; * enrolled in a competing study * previous participation in the MINT trial * any patient who in the judgment of the research team should not be enrolled in the trial. This would include, but not be limited to, factors such alcohol or drug dependence, or psychiatric illness.