The purpose of this study is to understand the use of Corus CAD also known as Age/Sex/Gene Expression score (ASGES) in the clinical decision making process of patients who underwent the evaluation of chest pain or anginal equivalent symptoms. Specifically, to better understand whether the use of the assay in clinical decision making resulted in changes in noninvasive diagnostic test ordering or diagnostic yield of additional tests ordered and/or invasive angiography.

The UCU-CARD (Understanding Clinician Utility-Cardiology) study is a retrospective, matched-cohort evaluation of diagnostic testing in a community-based cardiology practice setting that used a personalized age, sex, and gene expression test during early work-up of patients with symptoms suggestive of obstructive CAD (http://www.clinicaltrials.gov, NCT02223286). The study measured the rates of advanced cardiac diagnostic testing after initial work-up, including stress testing with imaging, CTA, or ICA. Rates of advanced diagnostic testing for patients who received the age, sex, and gene expression test (ASGES) were compared with testing rates for matched historical controls (usual care). The study hypothesis was that incorporating the age, sex, and gene expression testing early in the diagnostic work-up pathway would permit the identification of patients for whom advanced diagnostic testing was not required, thereby avoiding unnecessary testing and enabling cardiologists to focus their diagnostic resources more efficiently.

This single-center study was conducted at the North Phoenix Heart Center (Phoenix, AZ), a community-based group cardiology practice that receives patients on referral from primary care physicians and other specialists in the surrounding area. The practice incorporated age, sex, and gene expression testing into its diagnostic protocol beginning in June 2011. Data collection was completed in December 2013. Institutional Review Board (IRB) approval of the study protocol was granted by Quorum Review. Informed consent waivers were granted as data collection was retrospective and all data were de-identified.

Inclusion Criteria:

1. Symptoms suggestive of CAD, according to the opinion of the site clinician
2. Age >= 21 years

Exclusion Criteria:

1. History of myocardial infarction (MI)
2. History of high risk unstable angina, systemic infections or systemic inflammatory conditions
3. Current MI or acute coronary syndrome
4. Current New York Heart Association (NYHA) class III or IV congestive heart failure symptoms
5. Known/documented CAD
6. History/current Diabetes Mellitus
7. Taking steroids, immunosuppressive agents, or chemotherapeutic agents, at time of chest pain presentation

The patient population of interest and the main inclusion criterion for inclusion is the occurrence of chest pain (or anginal equivalent) in a patient without known significant CAD or a history of prior myocardial infarction, and the utilization of Corus CAD (Age/Sex/Gene Expression score - ASGES).

Additionally, subjects with similar chest pain (or angina equivalent) whom did not undergo Corus CAD (ASGES) will be included as a control group, to understand the diagnostic evaluation and management of patients prior to Corus CAD (ASGES) use.