Myocardial Ischemia and Transfusion Pilot

Red blood cell transfusions are extremely common medical interventions, yet, it remains unclear when patients should be transfused. This pilot study will evaluate the feasibility of conducting a research protocol that will lead to a large scale clinical trial designed to evaluate the treatment effectiveness of two transfusion threshold strategies in patients with coronary artery disease.

• Red blood cell transfusion (Biological): Liberal versus restrictive transfusion

Primary outcomes

• Hemoglobin Concentration [In-hospital up to 30 days post randomization]: Differences in the mean hemoglobin concentrations between the two study arms.
• Red Blood Cell Transfusion [In-hospital up to 30 days post randomization]: Differences in mean number of units of red blood cell transfusions between the two study arms.

Secondary outcomes

• Mortality or Myocardial Ischemia [30 days]: Composite 30 day rates of all cause 30 day mortality, or myocardial infarction (recurrent if had ST segment or Non ST segment MI or new myocardial infarction) up to 30 days after randomization, or unscheduled coronary revascularization within 30 days.
• Mortality or Myocardial Ischemia [6 months]: Composite 6 month rates of all cause 6 month mortality, recurrent myocardial infarction up to 6 months after randomization, unscheduled coronary revascularization within 6 months.
• Individual Components of Composite Outcome [30 days]: All cause mortality Myocardial infarction (recurrent if had ST segment or Non ST segment MI or new myocardial infarction) Unscheduled coronary revascularization.
• Mortality From Cardiac Causes [30 days]
• Unscheduled Hospital Admission [30 days]: Unscheduled hospital admission at 30 days for any reason, for cardiac reason (e.g., acute coronary syndrome, MI, congestive heart failure, or arrhythmia), or infection.
• Stroke [30 days]
• Congestive Heart Failure [30 days]
• Stent Thrombosis [30 days]
• Deep Vein Thrombosis or Pulmonary Embolism [30 days]
• Pneumonia or Blood Stream Infection and Each Separately [30 days]
• Composite Mortality and Morbidity [30 days]: Composite rates of all cause mortality, or myocardial infarction (recurrent if had ST segment or Non ST segment MI or new myocardial infarction), or unscheduled coronary revascularization or pneumonia.

Sex: All, ages: 18 Years to any

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.

Participant flow

Outcome results

• Hemoglobin Concentration (Primary), Mean, g/dL: Liberal Transfusion Strategy 10.30 +/- 1.00; Restrictive Transfusion Strategy 9.03 +/- 0.82 (p <0.001)
• Red Blood Cell Transfusion (Primary), Mean, blood units: Liberal Transfusion Strategy 1.58 +/- 1.13; Restrictive Transfusion Strategy 0.49 +/- 1.03 (p <0.001)
• Mortality or Myocardial Ischemia (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 6; Restrictive Transfusion Strategy 14
• Mortality or Myocardial Ischemia (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 15; Restrictive Transfusion Strategy 20
• Individual Components of Composite Outcome (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 1; Restrictive Transfusion Strategy 7
• Mortality From Cardiac Causes (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 1; Restrictive Transfusion Strategy 7
• Unscheduled Hospital Admission (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 9; Restrictive Transfusion Strategy 17
• Stroke (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 1; Restrictive Transfusion Strategy 0
• Congestive Heart Failure (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 2; Restrictive Transfusion Strategy 7
• Stent Thrombosis (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 0; Restrictive Transfusion Strategy 0
• Deep Vein Thrombosis or Pulmonary Embolism (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 1; Restrictive Transfusion Strategy 0
• Pneumonia or Blood Stream Infection and Each Separately (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 0; Restrictive Transfusion Strategy 2
• Composite Mortality and Morbidity (Secondary), Count of participants, Participants: Liberal Transfusion Strategy 6; Restrictive Transfusion Strategy 16

Adverse events

Time frame: Up to 6 months following randomization

Serious adverse events by term

Limitations and caveats: This pilot trial was not designed to enroll enough patients to answer the transfusion dilemma currently facing clinicians in practice.

• Results publication: Carson JL, Brooks MM, Abbott JD, Chaitman B, Kelsey SF, Triulzi DJ, Srinivas V, Menegus MA, Marroquin OC, Rao SV, Noveck H, Passano E, Hardison RM, Smitherman T, Vagaonescu T, Wimmer NJ, Williams DO. Liberal versus restrictive transfusion thresholds for patients with symptomatic coronary artery disease. Am Heart J. 2013 Jun;165(6):964-971.e1. doi: 10.1016/j.ahj.2013.03.001. Epub 2013 Apr 8. PMID 23708168
• Results publication: Carson JL, Stanworth SJ, Dennis JA, Fergusson DA, Pagano MB, Roubinian NH, Turgeon AF, Valentine S, Trivella M, Doree C, Hebert PC. Transfusion thresholds and other strategies for guiding red blood cell transfusion. Cochrane Database Syst Rev. 2025 Oct 20;10(10):CD002042. doi: 10.1002/14651858.CD002042.pub6. PMID 41114449
• Results publication: Carson JL, Stanworth SJ, Dennis JA, Trivella M, Roubinian N, Fergusson DA, Triulzi D, Doree C, Hebert PC. Transfusion thresholds for guiding red blood cell transfusion. Cochrane Database Syst Rev. 2021 Dec 21;12(12):CD002042. doi: 10.1002/14651858.CD002042.pub5. PMID 34932836

• Jeffrey L Carson, MD, Study chair, Rutgers, The State University of New Jersey
• Sheryl F Kelsey, PhD, Principal investigator, University of Pittsburgh Data Coordinating Center

NIH grants: 1RC2HL101458-01