Background: Patients with symptoms suggestive of obstructive coronary artery disease (CAD) frequently undergo unnecessary testing and procedures. Approximately $5.9 billion/year is spent on non-invasive and invasive cardiac testing among non-diabetic patients in the US without a prior revascularization or myocardial infarction, yet clinicians are often unable to confidently determine the primary etiology of symptoms suggestive of obstructive CAD. A previously validated blood-based test, incorporating age, sex, and gene expression levels into an algorithmic score, has been shown to have a 96% NPV and can inform the current likelihood of CAD in a symptomatic patient.
Objective: The objective of the PRESET Registry is to evaluate the use of an age/sex/gene expression score (ASGES) and its effects on medical decision-making, with a focus on referrals to cardiology or advanced cardiac testing, in a community-based cardiovascular registry.
Methods: The prospective PRESET Registry (NCT01677156) enrolled stable, non-acute adult patients without a history of CAD from 21 US primary care practices from September 2012 to August 2014. Primary care clinicians provided the pre- and post-ASGES diagnosis and evaluation plan for each patient. Demographics, clinical factors, and ASGES results (predefined as low [ASGES ≤15] or elevated [ASGES >15]) were collected, as were management plans post-ASGES testing, including referrals to cardiology or further functional/anatomic (ETT, MPI, CTCA, stress echo, ICA) cardiac testing. Patients were followed to 30 days post-ASGES for the primary analysis of the association between ASGES and subsequent cardiac testing. Up to 1 year follow-up will be conducted for all patients.
Results: Among the evaluable cohort of 718 patients, 369 (51%) were women, the median age was 58 and the median BMI was 30. The median ASGES was 18 (range, 1-40), and 310 patients (43%) had low scores. Thirty days after testing, 27 of 310 (9%) patients with low scores were referred to cardiology or advanced diagnostic testing, while 143 of 408 (35%) patients with elevated scores were referred (OR 0.18, p<0.0001). With regard to adverse outcomes, there were 2 events (stroke/TIA) overall, which were judged to be unrelated to the study procedure.
Conclusion: In this analysis of a community-based cardiovascular registry, the age/ex/gene expression test was adopted in clinical practice and associated with a statistically significant and clinically relevant effect on medical decision making in patients presenting with typical or atypical symptoms suggestive of obstructive CAD. The use of the ASGES test showed clinical utility in helping clinicians efficiently and safely rule out obstructive CAD as the cause of their patients’ symptoms, thereby minimizing potentially unnecessary referral of low risk patients to cardiology and further cardiac diagnostic testing.