Product Overview

What is Corus CAD?

Corus® CAD is the only blood test that can help you quickly and safely assess whether or not your patient's chest discomfort or other symptoms are due to obstructive* coronary artery disease (CAD). Corus CAD is a decision-making tool that can help identify patients unlikely to have obstructive CAD and help you determine appropriate next steps for patient management.

  • Clinically validated in two large, prospective, multicenter studies in the U.S. called PREDICT1 and COMPASS2
  • Provides an assessment of your patient's current disease state without risks associated with imaging radiation, imaging agents, and/or contrast solutions
  • Integrates the expression levels of 23 genes involved in the development of and/or response to atherosclerosis into a single score, which has been proven to accurately identify patients without obstructive CAD
  • Represents the first sex-specific test for CAD that accounts for key biological differences between men and women
  • Has high sensitivity and negative predictive value, and improves the classification of patient disease status1, 2

Why do I need Corus CAD in my practice?

Cardiovascular diseases, or CVDs, are the leading cause of death worldwide. In the U.S., CAD, one of the most common CVDs, accounts for nearly one in six deaths according to the American Heart Association3. We estimate that approximately three million nondiabetic patients in the U.S. with no prior revascularization, such as stenting or bypass surgery, and no prior myocardial infarction (heart attack), visit their primary care provider each year complaining of symptoms that may be suggestive of obstructive CAD. Studies have shown that only approximately 10% of patients who present to their primary care providers with symptoms suggestive of obstructive CAD actually have obstructive CAD, while the remaining approximately 90% of patients have symptoms that stem from other non-cardiac conditions, such as musculoskeletal disorders, gastrointestinal disease and psychosocial syndromes.4, 5

Moreover, recent evidence from the New England Journal of Medicine suggests that current modalities for identifying which patients should undergo elective, invasive coronary angiography to diagnose CAD have limitations, and that better methods are needed for patient risk stratification.6

Why gene expression?

Corus CAD is a gene expression test, not a genetic test. Whereas genetic testing may inform on lifetime disease risk, the Corus CAD gene expression test provides a current-state assessment of obstructive CAD by looking at the gene expression changes associated with atherosclerosis. Gene expression levels change depending on a person's disease status resulting from genetic and environmental factors. Combining the Corus CAD gene expression test with other noninvasive assessments provides you with a more complete picture of your patient’s coronary artery disease status through its clinical utility in identifying patients unlikely to have obstructive CAD.1, 2, 7

How do I use Corus CAD?

As a blood test that can be easily integrated into any practice setting, Corus CAD:

  • Is performed through a quick, routine blood draw conveniently administered right in your office
  • Provides objective, reproducible results within 72 hours
  • Complements your current noninvasive assessment of CAD, while improving diagnostic accuracy for obstructive CAD1, 2

Who is the Corus CAD patient?

For information on which patients are appropriate for Corus CAD, please see Corus CAD Patient Selection.

For a complete description of the intended use population for Corus CAD, please see the Corus CAD Intended Use Statement.

To help you incorporate Corus CAD into your practice, CardioDx® provides:

  • Clinician product support and procedure training
  • Specialized consultations with a CardioDx clinician to assist in patient selection and test result interpretation
  • Easy, 24-hour access to your patients' reports and customized charts, as well as tables, through a secure, web-based Clinician Access Portal
  • A dedicated team of insurance experts available to work with patients, clinicians, and payers to obtain positive reimbursement through billing and appeals. The team can also assist by providing financial assistance through the CARE Patient Financial Assistance Program

Expression of Insight



* Obstructive CAD is defined as at least one atherosclerotic plaque causing ≥50% luminal diameter stenosis in a major coronary artery (≥1.5 mm lumen diameter) as determined by invasive quantitative coronary angiography (QCA) or core-lab computed tomography angiography (CTA) (≥2.0 mm).

  1. Rosenberg S, Elashoff MR, Beineke P, et al. Multicenter Validation of the Diagnostic Accuracy of a Blood-Based Gene Expression Test for Assessing Obstructive Coronary Artery Disease in Nondiabetic Patients. Ann Intern Med. 2010;153:425-434.
  2. Thomas GS, Voros S, McPherson JA, et al. A Blood-Based Gene Expression Test for Obstructive Coronary Artery Disease Tested in Symptomatic Nondiabetic Patients Referred for Myocardial Perfusion Imaging: The COMPASS Study. Circulation: Cardiovascular Genetics. 2013;6(2):154-162.
  3. Go SO, Mozaffarian D, Roger VL, et al. on behalf of the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Heart Disease and Stroke Statistics--2013 Update: A Report from the American Heart Association. Circulation. 2013;127(1):e6-e245.
  4. Cayley WE Jr. Diagnosing the Cause of Chest Pain. Am Fam Physician. 2005;72(10):2012-2021.
  5. National Ambulatory Medical Care Survey, 2010.
  6. Patel MR, Peterson ED, Dai D, et al. Low Diagnostic Yield of Elective Coronary Angiography. N Engl J Med. 2010;362:886–895.
  7. McPherson JA, Davis K, Yau M, et al. The Clinical Utility of Gene Expression Testing on the Diagnostic Evaluation of Patients Presenting to the Cardiologist with Symptoms of Suspected Obstructive Coronary Artery Disease: Results From the IMPACT (Investigation of a Molecular Personalized Coronary Gene Expression Test on Cardiology Practice Pattern) Trial. Crit Pathw Cardiol. 2013;12(2):37-42.