ISSN 2996-8215
International Journal of Cardiology | Vol. 13, No. 8, August 2022 | pp. 57–64
DOI: 10.46882/2022/IJC/000161
Original Research Article
Diagnostic Utility of High-Sensitivity Cardiac Troponin I 0-Hour/1-Hour Rapid Triage Algorithm for Myocardial Infarction Rule-Out
Chloe Jenkins¹, Oliver Vance¹, Sarah E. Lawson²
¹Emergency Department, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
²School of Medicine, University of Queensland, Brisbane, Queensland, Australia
Abstract:
Accelerated diagnostic protocols utilizing high-sensitivity cardiac troponin I (hs-cTnI) assays have the potential to substantially shorten evaluation times for patients presenting to the emergency department (ED) with suspected acute coronary syndrome. This prospective diagnostic study evaluated the safety and clinical efficacy of an accelerated 0-hour/1-hour rule-out algorithm using hs-cTnI in patients presenting with acute chest pain. We evaluated 450 consecutive patients presenting to the ED with chest pain suggestive of myocardial ischemia. Serial blood samples were obtained at presentation (0h) and exactly 1 hour later. The final diagnosis of acute myocardial infarction (AMI) was adjudicated by an independent clinical panel using the universal definition. AMI was diagnosed in 62 patients (13.8%). A baseline hs-cTnI level below 5 ng/L or a 1-hour absolute change less than 3 ng/L successfully ruled out AMI in 61.3% of the cohort. This rapid protocol yielded an overall diagnostic sensitivity of 98.4% (95% CI: 91.3%–99.9%) and an exceptional negative predictive value (NPV) of 99.6% (95% CI: 98.0%–99.9%). The specificity and positive predictive value (PPV) were 68.4% and 33.2%, respectively. No patient classified as safe for early rule-out experienced an un-adjudicated myocardial infarction or major adverse cardiac event within a 30-day safety follow-up window. A rapid 0h/1h accelerated diagnostic protocol incorporating a high-sensitivity cardiac troponin I assay allows for safe, exceptionally fast exclusion of acute myocardial infarction in more than half of presenting ED chest pain patients.
Keywords: High-sensitivity cardiac troponin I, Acute myocardial infarction, Emergency department, Chest pain, Rapid rule-out, Negative predictive value
Received: May 12, 2022; Revised: June 25, 2022; Accepted: July 14, 2022; Published: August 20, 2022