USA: In a recent study published in JAMA Cardiology, the researchers found that changes in high-sensitivity troponin T (hsTnT) are associated with a gradient of risk of successive cardiovascular events among stable patients with post-acute coronary syndrome (ACS).
The study showed that in patients with established atherosclerosis, serial hsTnT assessment might refine risk stratification for cardiovascular events and help inform treatment decision-making in this patient population.
Previous studies have shown that in patients with chronic coronary syndromes, there is an association between single measures of high-sensitivity troponin (hsTn) and future cardiovascular events. However, not much data is available regarding the association between changes in serial values of hsTn and subsequent cardiovascular events in these patients.
Considering the above, Siddharth M. Patel, from USA, and colleagues aimed to investigate the association between changes in hsTnT and subsequent cardiovascular events in patients stabilized after acute coronary syndrome.
Improved Reduction of Outcomes: Vytorin Efficacy International Trial (IMPROVE-IT) is a randomized clinical trial of ezetimibe vs. placebo on a background of simvastatin in 18 144 hospitalized patients for an ACS across 1147 sites in 39 countries. The researchers conducted a secondary analysis of the IMPROVE-IT trial. The substudy included 6035 participants allowing the biomarker substudy with the available hsTnT at months 1 and 4.
Myocardial infarction (MI), stroke, cardiovascular death, or hospitalization for heart failure (HHF) were deemed the outcomes of interest. Using landmark analyses, the researchers examined the associations of absolute and relative changes in hsTnT through 1 to 4 months as a function of the month one hsTnT and the composite outcome.
The study led to the following findings:
- Of 6035 patients in this analysis (median age, 64), 24.6% were female).
- Most patients (68.2%) had stable hsTnT values (change <3 ng/L), with 19.2% and 12.6% having changes of 3 to less than 7 ng/L and 7 ng/L or more, respectively.
- After adjustment for clinical risk factors and stratification by the starting month one hsTnT level, an absolute increase in hsTnT of 7 ng/L or more was associated with a more than the 3-fold more significant risk of the composite outcome (adjusted hazard ratio [aHR], 3.33). In contrast, decreases of 7 ng/L or more were associated with similar to lower risk (aHR, 0.51) compared with stable values.
- There was a stepwise association moving from more significant absolute decreases (aHR, 0.51) to larger total increases (aHR, 3.33) in hsTnT with future risk of the composite outcome.
- A similar association was observed when analyzed based on relative percent and continuous change.
“hsTnT changes were associated with a gradient of risk of subsequent cardiovascular events across the range of starting hsTnT values among stable patients post-ACS,” the researchers wrote in their conclusion. “Serial hsTnT assessment may refine risk stratification with the potential to guide therapy decisions in these patients.”
Reference:
Patel SM, Qamar A, Giugliano RP, et al. Association of Serial High-Sensitivity Cardiac Troponin T With Subsequent Cardiovascular Events in Patients Stabilized After Acute Coronary Syndrome: A Secondary Analysis From IMPROVE-IT. JAMA Cardiol. Published online October 19, 2022. doi:10.1001/jamacardio.2022.3627