International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA)


  • Study type

  • Study IDs

  • Describes the nature of a clinical study. Types include:

    • Observational study — observes people and measures outcomes without affecting results.
    • Interventional study (clinical trial) — studies new tests, treatments, drugs, surgical procedures or devices.
    • Medical records research — uses historical information collected from medical records of large groups of people to study how diseases progress and which treatments and surgeries work best.
  • Site IRB
    • Rochester, Minnesota: 12-007224
    NCT ID: NCT01471522
    Sponsor Protocol Number: 12-007224

About this study

The purpose of the ISCHEMIA trial is to determine the best management strategy for higher-risk patients with stable ischemic heart disease. This is a multicenter randomized controlled trial with a target enrollment of ~8000 patients with at least moderate ischemia on stress imaging. Patients will be assigned at random to a routine invasive strategy (INV) with cardiac catheterization (cath) followed by revascularization plus optimal medical therapy (OMT) or to a conservative strategy (CON) of OMT, with cath and revascularization reserved for those who fail OMT.


A. Primary Aim

The primary aim of the ISCHEMIA trial is to determine whether an initial invasive strategy of cardiac catheterization followed by optimal revascularization, if feasible, in addition to OMT, will reduce the primary composite endpoint of cardiovascular death or nonfatal myocardial infarction in participants with SIHD and at least moderate ischemia over an average follow-up of approximately 4 years compared with an initial conservative strategy of OMT alone with catheterization reserved for failure of OMT. The primary endpoint is time to centrally adjudicated cardiovascular death or nonfatal myocardial infarction.

B. Secondary Aims Major

To compare angina-related quality of life between groups. Other secondary aims include: a) comparing the incidence of all-cause death; the components of the primary endpoint; the composite endpoint of cardiovascular death, myocardial infarction, or hospitalization for unstable angina, resuscitated cardiac arrest, or heart failure; stroke; and stroke combined with cardiovascular death, myocardial infarction, or hospitalization for unstable angina, resuscitated cardiac arrest, or heart failure between randomized groups; and b) comparing health resource utilization, costs, and cost-effectiveness between groups.

Condition: Coronary Disease Procedure: Coronary CT Angiogram Procedure: Cardiac catheterization Phase: Phase III

Condition: Cardiovascular Diseases Procedure: Angioplasty, Transluminal, Percutaneous Coronary, other catheter-based interventions Phase: Phase III

Condition: Heart Diseases Procedure: Coronary Artery Bypass Surgery Phase: Phase III

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. If you need assistance understanding the eligibility criteria, please contact the study team.

See eligibility criteria

Inclusion Criteria:

  • At least moderate ischemia on an ischemia test
  • Participant is willing to comply with all aspects of the protocol, including adherence to the assigned strategy, medical therapy and follow-up visits
  • Participant is willing to give written informed consent
  • Age ≥ 21 years

Exclusion Criteria:

  • LVEF < 35%
  • History of unprotected left main stenosis >50% on prior coronary computed tomography angiography (CCTA) or prior cardiac catheterization (if available)
  • Finding of "no obstructive CAD" (<50% stenosis in all major epicardial vessels) on prior CCTA or prior catheterization, performed within 12 months
  • Coronary anatomy unsuitable for either PCI or CABG
  • Unacceptable level of angina despite maximal medical therapy
  • Very dissatisfied with medical management of angina
  • History of noncompliance with medical therapy
  • Acute coronary syndrome within the previous 2 months
  • PCI within the previous 12 months
  • Stroke within the previous 6 months or spontaneous intracranial hemorrhage at any time
  • History of ventricular tachycardia requiring therapy for termination, or symptomatic sustained ventricular tachycardia not due to a transient reversible cause
  • NYHA class III-IV heart failure at entry or hospitalization for exacerbation of chronic heart failure within the previous 6 months
  • Non-ischemic dilated or hypertrophic cardiomyopathy
  • End stage renal disease on dialysis or estimated glomerular filtration rate (eGFR) <30mL/min (not an exclusion criterion for CKD ancillary trial, see CKD ancillary trial, Section 18)
  • Severe valvular disease or valvular disease likely to require surgery or percutaneous valve replacement during the trial
  • Allergy to radiographic contrast that cannot be adequately pre-medicated, or any prior anaphylaxis to radiographic contrast
  • Planned major surgery necessitating interruption of dual antiplatelet therapy (note that patients may be eligible after planned surgery)
  • Life expectancy less than the duration of the trial due to non-cardiovascular comorbidity
  • Pregnancy (known to be pregnant; to be confirmed before CCTA and/or randomization, if applicable)
  • Patient who, in the judgment of the patient's physician, is likely to have significant unprotected left main stenosis (Those who are able to undergo CCTA will have visual assessment of the left main coronary artery by the CCTA core lab)
  • Enrolled in a competing trial that involves a non-approved cardiac drug or device
  • Inability to comply with the protocol
  • Exceeds the weight or size limit for CCTA or cardiac catheterization at the site
  • Canadian Cardiovascular Society Class III angina of recent onset, OR angina of any class with a rapidly progressive or accelerating pattern
  • Canadian Cardiovascular Society Class IV angina, including unprovoked rest angina
  • High risk of bleeding which would contraindicate the use of dual antiplatelet therapy
  • Cardiac transplant recipient
  • Prior CABG, unless CABG was performed more than 12 months ago, and coronary anatomy has been demonstrated to be suitable for PCI or repeat CABG to accomplish complete revascularization of ischemic areas (CCC approval required)

Participating Mayo Clinic locations

Study statuses change often. Please contact us for help.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Todd Miller, M.D.

Open for enrollment

Contact information:

So Yang Cho R.N.



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