Age and the European Society of Cardiology 0/1-hour high sensitivity troponin T algorithm for the evaluation of patients with possible acute myocardial infarction: results from the STOP-CP study
Authors: Allen B R , Ashburn N P , Snavely A C , Paradee B E , Christenson R H , Nowak R M , Mumma B E , Madsen T , O'Neill J C , Stopyra J P , Mahler S A 
Published: October 2022

Abstract

Background
The European Society of Cardiology (ESC) 0/1-hour high sensitivity troponin (hs-cTn) algorithm is widely used in the evaluation of patients presenting to the Emergency Department (ED) with symptoms suspicious for non ST-segment elevation myocardial infarction (NSTEMI). The effect of increasing patient age with its use has not been studied in any detail.

Purpose
The objective of this secondary analysis of the STOP-CP (High Sensitivity Cardiac Troponin T to Optimize Chest Pain Risk Stratification) United States (US) multicenter study was to evaluate the efficacy and safety of use of the ESC 0/1-hour hs-cTnT algorithm in younger, middle-aged, and older patients.

Methods
Patients (≥21 years old) presenting to the (ED) with symptoms suggestive of NSTEMI were enrolled (1/25/2017–9/6/2018) at 8 US medical centers. The ESC hs-cTnT 0/1-hour hs-cTnT algorithm was used to place patients into rule-out, observe, and rule-in NSTEMI zones. Algorithm performance for rapid NSTEMI rule-out and 30-day adverse outcomes was studied in 3 patient age (years) intervals: younger (21–45). middle aged (46–64) and older (≥65). Major adverse cardiovascular events (MACE) consisted of cardiac death, myocardial infarction, or coronary revascularization at 30-days. Fisher's exact tests were used to compare NSTEMI ruled out and MACE rates between patient age intervals. Negative likelihood ratios (NLR) with 95% confidence interval (CI) were calculated for 30-day MACE.

Results
Overall 1430 participants were enrolled with 15.7% (224/1430) young, 57.4% (821/1430) middle-aged, and 26.9% (385/1430) being older. The ESC 0/1 hour hs-cTnT algorithm NSTEMI rule-out rates were 79.9% (179/224), 62.1% (510/821) and 35.6% (137/385) respectively for these age groups (p&lt;0.0001). The overall 30-day MACE rate was 14.2% (203/1430) with interval age rates of 7.1% (16/224) in younger, 13.1% (108/821) middle aged and 20.5% (79/385) older patients. Amongst NSTEMI ruled-out patients MACE occurred in 1.1% (2/179) of younger, 3.3% (17/510) middle aged and 2.9% (4/137) older individuals (p=0.320). NLR for 30-day MACE was 0.15 (95% CI 0.04, −0.54) in younger, 0.23 (95% CI 0.15–0.35) middle aged and 0.12 (95% CI 0.04–0.31) for older patients.

Conclusions
With increasing age ED patients were less often rapidly ruled out for NSTEMI during their initial cardiac evaluations. The STOP-CP US study demonstrated that older age interval alone was not an independent variable that increased the risk for 30-day MACE in patients ruled out for NSTEMI using the ESC 0/1 hour hs-cTnT algorithm. Our report suggests that cardiac risk stratification scores using age as an independent variable for predicting 30-day MACE in these patients require reevaluation.

Funding Acknowledgement
Type of funding sources: Private company. Main funding source(s): Roche, Basel, Switzerland