Abstract
BACKGROUND: Chest pain is a common emergency department (ED) presentation, and early risk stratification is essential to identify patients at risk of major adverse cardiac events (MACE). OBJECTIVE: This study aimed to evaluate the diagnostic and prognostic utility of high-sensitivity troponin T (hs-TnT) and the HEART (history, ECG, age, risk factors, and troponin) score in predicting 30- and 45-day MACE among patients presenting with chest pain. METHODOLOGY: This descriptive observational study was conducted in two tertiary-care EDs in Pakistan (June 2021-May 2022). A total of 864 adult patients with non-traumatic chest pain were enrolled. Baseline demographics, clinical features, and risk factors were recorded. Initial hs-TnT levels were measured at presentation and serially at one and three hours. HEART scores were calculated at admission. MACE (myocardial infarction, revascularization, or cardiac death) within 30 and 45 days was defined according to standard criteria and adjudicated independently by blinded cardiologists. Associations between hs-TnT and outcomes were analyzed using chi-square tests for categorical variables and independent t-tests for continuous variables. Missing data were excluded from the analysis. RESULTS: Among 864 patients (mean age 57.8 ± 13.1 years; 62% male), 144 (16.7%) developed 30-day MACE and 166 (19.2%) 45-day MACE. Patients with hs-TnT >52 ng/L had markedly higher MACE risk (30-day: 58.6%; 45-day: 63.8%) compared with those with hs-TnT <5 ng/L (30-day: 1.7%; 45-day: 1.9%, p<0.001). A HEART score ≥7 predicted 30-day MACE with 51.2% sensitivity, 87.3% specificity, a positive predictive value (PPV) of 28.2%, and a negative predictive value (NPV) of 94.6%. hs-TnT >52 ng/L alone showed 73.2% sensitivity, 79.4% specificity, PPV 35.7%, and NPV 95.9%. Combining hs-TnT >52 ng/L with HEART score ≥4 improved sensitivity to 84.2% and NPV to 97.2%. The area under the receiver operating characteristic (ROC) curve (AUC) for hs-TnT alone was 0.81 (95% CI: 0.77-0.85), for HEART score ≥7 was 0.76 (95% CI: 0.72-0.80), and for the combined model was 0.86 (95% CI: 0.83-0.89). CONCLUSION: Hs-TnT and the HEART score are effective, complementary tools for early identification of patients at risk of MACE. Serial hs-TnT measurement and combined use with HEART scoring significantly improve predictive accuracy, supporting their integration into ED risk stratification protocols.