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If you are a site that was participating in the ISCHEMIA study, are currently participating in ISCHEMIA-EXTEND or would like to learn more about future studies (ISCHEMIA-HF or CABG-SHOCK) please contact for more information.

Rationale of the ISCHEMIA Study

The results of Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) and the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trials demonstrated that in patients with stable ischemic heart disease (SIHD), an initial management strategy of revascularization plus optimal medical therapy (OMT) did not reduce the risk of death or MI as compared with OMT alone. Both trials randomized patients after cardiac catheterization.

Following the evidence provided by COURAGE and BARI 2D, a clinical trial that randomizes SIHD patients at a uniformly higher risk prior to cardiac catheterization was needed to determine optimal management for patients with SIHD.

For more information, see the NIH RePORT for the ISCHEMIA trial.  Also posted are the ISCHEMIA protocol versions:

ISCHEMIA Study Design

A total of 320 research centers worldwide participated in ISCHEMIA and enrolled 5,179 participants.

Eligible participants were recruited following a clinically indicated stress testing, but before catheterization, and randomized in a 1:1 fashion to one of two groups:

  • Invasive (INV) Management: Study participants in this group underwent a cardiac catheterization within 30 days of randomization; if significant coronary artery disease was present, coronary revascularization was performed. In addition, study participants in this group received optimal medical therapy (OMT).
  • Conservative (CON) Management: Study participants in this group received optimal medical therapy (OMT) alone with catheterization and possibly revascularization if the participant did not respond to optimal medical therapy.

For more information, please visit

Ancillary Studies


Patients with CKD are at increased risk of death from cardiovascular causes-15 to 30 times higher than age matched patients without CKD. However, most cardiovascular trials, including COURAGE and BARI-2D, have routinely excluded patients with CKD or included only a small proportion of these patients. Priot to ISCHEMIA CKD, there was a paucity of data as how to best manage SIHD in patients with CKD.

The International Study of Comparative Health Effectiveness with Medical and Invasive Approaches- Chronic Kidney Disease trial (ISCHEMIA-CKD) was an international comparative effectiveness study to determine the best way to manage stable ischemic heart disease in patients with advanced chronic kidney disease (eGFR <30 or on dialysis).

Patients with advanced CKD and ischemia on stress test were eligible for participation. The trial was designed to run seamlessly in parallel to the main ISCHEMIA trial.

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CIAO-ISCHEMIA stands for Changes in Ischemia and Angina over One year among ISCHEMIA trial screen failures with no obstructive corornary artery disease on coronary CT angiography. 

Patients were eligible if they have been enrolled in the ISCHEMIA Main Trial and their CCTA did not show any obstructive coronary obstructive disease. 

ISCHEMIA Biorepository 

The ISCHEMIA Biorepository serves as a resource for further investigation and analysis. The ISCHEMIA Biorepository will provide a wealth of opportunities for ancillary studies and sharing of resources with other investigators.

All participants in the main ISCHEMIA trial were given the opportunity to participate in ISCHEMIA Biorepository, local/national regulations and site availability/facilities permitting.