UK: Cardiac troponin predicts the risk of cardiovascular death or myocardial infarction (MI) in patients with chronic coronary artery disease, a recent study published in the Journal of the American College of Cardiology has shown.
For now, routine troponin testing is not recommended for patients with chronic coronary artery disease despite studies showing its prognostic value in some people with asymptomatic heart disease or heart attack survivors.
Cardiac troponin is already established for risk stratification of patients with acute coronary syndrome (ACS), however, the role of testing in other settings remains unclear. Therefore, Ryan Wereski, University of Edinburgh, Edinburgh, United Kingdom, and colleagues aimed to evaluate whether cardiac troponin testing could enhance risk stratification in patients with chronic coronary artery disease (CAD) independent of conventional risk measures and disease severity.
For this purpose, the researchers measured high-sensitivity cardiac troponin I (hs-cTn) before angiography in a prospective cohort of consecutive patients with symptoms suggestive of stable angina attending for outpatient coronary angiography, and clinicians were blinded to the results so as not to alter the course of subsequent clinical care. The primary outcome was determined as myocardial infarction or cardiovascular death during follow-up.
The authors reported the following findings:
In 4,240 patients (age 66 years, 33% were females), coronary artery disease was identified in 92% who had 255 primary outcome events during a median follow-up of 2.4 years.
In patients with coronary artery disease, troponin concentrations were 2-fold higher in those with an event compared with those without (6.7 ng/L versus 3.3 ng/L).
Troponin concentrations were associated with the primary outcome after adjusting for cardiovascular risk factors and coronary artery disease severity (adjusted HR: 2.3).
A troponin concentration >10 ng/L identified patients with a 50% increase in the risk of myocardial infarction or cardiovascular death.
"Recognizing that increasing severity of angina is associated with worse outcomes because of more adverse anatomy, it may be that hs-cTn is beneficial in higher-risk patients with more symptoms rather than in those with mild or no symptoms," Yader Sandoval, Minneapolis Heart Institute, Abbott Northwestern Hospital, and Allan Jaffe, Mayo Clinic in Rochester, Minnesota wrote in an accompanying editorial.
The study authors cautioned that this study cohort may not represent the full spectrum of chronic CAD.
"Further studies are needed to evaluate whether routine testing could inform the selection of high-risk patients for treatment intensification," they concluded.
Reference:
Wereski R, et al "High-sensitivity cardiac troponin for risk assessment in patients with chronic coronary artery disease" J Am Coll Cardiol 2023; DOI: 10.1016/j.jacc.2023.05.046.