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

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<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

Patients with known coronary artery disease who are ruled out for acute myocardial infarction using a high sensitivity troponin T 0/1-hour algorithm have increased 30-day major adverse cardiac events

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). There is limited data available for the use of this algorithm comparing NSTEMI rule-out rates and 30-day adverse outcomes in patients with and without known coronary artery disease (CA), defined as prior myocardial infarction [MI], coronary revascularization, or ≥70% coronary stenosis.

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 compare the ESC 0/1-hour algorithm for rapid NSTEMI rule-out and 30-day adverse outcomes in patients with and without known CAD.

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 stratify patients into rule-out, observe, and rule-in zones. Algorithm performance for 30-day adverse outcomes was analyzed in patients with or without known CAD. Major adverse cardiovascular events (MACE) consisted of cardiac death, MI, or coronary revascularization. Fisher's exact tests were used to compare NSTEMI rule-out and 30-day MACE rates in patients with and without known CAD. Negative likelihood ratios (NLR) with a 95% confidence interval (CI) were calculated for 30-day MACE.

Results

Overall 1430 patients were enrolled. Of these 31.4% (449/1430) had known CAD while 14.2% (203 /1430) experienced 30-day MACE. Using the ESC 0/1-hour hs-cTnT algorithm 39.6% (178/449) of patients with known CAD were placed in the rule-out zone compared to 66.1% (648/981) without CAD (p<0.0001). Of patients with known CAD 23.2% (104/449) had 30-day MACE compared to 10.1% (99/981) of those without known CAD (p<0.0001). Additionally, amongst those patients placed in the rule-out zone, 30-day MACE occurred in 7.9% (14/178) of individuals with known CAD and 1.4% (9/648) of those without known CAD (p<0.0001). NLR for 30-day MACE was 0.28 (95% CI 0.17–0.47) in patients with known CAD and 0.13 (95% CI 0.07–0.23) in those without CAD.

Conclusions

In the multicenter US STOP-CP study patients with known CAD were less often rapidly ruled out for NSTEMI and had higher 30-day MACE rates than those without known CAD. Patients with known CAD who were rapidly ruled out for NSTEMI had a higher 30-day MACE rate compared to those without known CAD. Our analysis suggests that patients with known CAD require further cardiac reevaluations whether they are ruled out for NSTEMI by the ESC 0/1 hour hs-cTnT algorithm or not.

Funding Acknowledgement

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