EFFICACY OF HIGH-SENSITIVITY TROPONIN T IN IDENTIFYING VERY-LOW-RISK PATIENTS WITH POSSIBLE ACUTE CORONARY SYNDROME: A CASE STUDY FROM AL AMEEN MEDICAL COLLEGE

Background: High-sensitivity troponin T (hsTnT) assays enable refined risk stratification in emergency department (ED) patients with possible acute coronary syndrome (ACS).This study evaluates a dual-sampling protocol utilizing a locally validated 99th percentile upper reference limit (URL) for identifying very-low-risk patients amenable to expedited discharge.Methods:A prospective cohort of 80 consecutive patients with suspected ACS underwent hsTnT quantification via electrochemiluminescence immunoassay at presentation (0h) and 3 hours post-admission.The 99th percentile URL (19 ng/L) was derived from 50 asymptomatic local volunteers. Primary outcome was 30-day adverse cardiac events (ACE), encompassing myocardial infarction (MI), urgent revascularization, or cardiac mortality. Diagnostic performance metrics—sensitivity, specificity,positive predictive value (PPV),and negative predictive value (NPV)—were computed with Clopper-Pearson 95% confidence intervals (CIs).Results:The rule-out cohort (hsTnT ≤19 ng/L at 0h/3h; n=60) exhibited a 30-day ACE incidence of 1.7% (95% CI: 0.3–8.1), yielding an NPV of 99.2% (95% CI: 96.5–99.9). Conversely, the non-rule-out cohort (hsTnT >19 ng/L; n=20) demonstrated a 20% ACE incidence (95% CI: 8.1–39.8).HsTnT ≤19 ng/L at 0h conferred an NPV of 98.1% (95% CI:94.3–99.4) for index MI.Conclusion: Serial hsTnT measurements ≤19 ng/L at 0h and 3h identify patients with minimal 30-day ACE risk (NPV >99%), validating this protocol as a pivotal tool for rapid ED discharge in resource-constrained settings.