A Registry to Evaluate Patterns of Care Associated With the Use of Corus® CAD in Real World Clinical Care Settings (PRESET)

Though the diagnostic properties of Corus® CAD have been evaluated in previous observational studies, there are limited data regarding how primary care clinicians are using the results of the test in the care and management of patients with angina. This registry is designed to examine the relationship between the Corus CAD score and patterns of care regarding diagnostic testing in real world clinical care settings.

Atherosclerotic coronary artery disease (CAD) is the most common cause of morbidity and mortality worldwide. CAD affects 16.5 million persons in the US. Diagnosing CAD is not straightforward and poses an enormous burden on the health care system. The most common symptom of CAD is chest pain (angina), however, only 10%-30% of chest pain and related symptoms are due to CAD. Though there are several diagnostic tests for CAD (e.g., coronary angiography, stress testing, nuclear myocardial perfusion imaging (MPI)), each has its limitations, including invasiveness, safety risks (e.g., bleeding, radiation exposure), expense, lack of accuracy, subjectivity in evaluation and interpretation of findings, and lack of availability in all geographic regions.

Recent scientific findings demonstrate that multiple genes are activated in circulating blood cells in patients with CAD. A gene expression test that detects activated and/or deactivated genes could therefore serve as a tool in aiding the diagnosis of CAD. The Corus® CAD test (henceforth, "Corus CAD") is a validated quantitative in vitro diagnostic test, performed in a single Clinical Laboratory Improvement Amendments (CLIA ) laboratory at CardioDx, Inc., using the gene expression level of 23 genes from peripheral blood specimens to assess the likelihood of a subject having at least a 50% coronary artery stenosis. Corus CAD incorporates the expression levels of these genes, using a validated algorithm with weighted functions, to generate a quantitative score and is indicated for use in stable patients with typical or atypical symptoms suggestive of CAD (e.g., chest pain, shortness of breath, heartburn, fatigue on exertion). The test is non-invasive (involving simple venipuncture), and as the results are evaluated at one laboratory, there is minimal potential variability in the analysis of findings.