title: Time to shift from contemporary to high-sensitivity cardiac troponin in diagnosis of acute coronary syndromes.
abstract: Early rule-in and rule-out of non-ST-segment elevation myocardial infarction (NSTEMI) is a challenge. In patients with inconclusive findings on ECG, cardiac biomarkers play a crucial role in the diagnosis. The introduction of the new high-sensitive cardiac troponin test (hs-TnI assay) has changed the landscape of NSTEMI diagnosis. The new hs-TnI assay can detect troponin values at a lower level compared with a contemporary cardiac troponin (cTn) assay. The hs-cTnI assay has a coefficient of variation of ≤10%, well below the 99th percentile value. It reduces the time to diagnose acute myocardial infarction from 6h to 3h. A recent study has demonstrated that hs-cTnI can further reduce the time to 1h in 70% of all patients with chest pain. The European Society of Cardiology 2015 guidelines recommend including a second sample of hs-cTnI within 3h of presentation This increases the sensitivity of the hs-TnI assay from 82.3% (at admission) to 98.2% and negative predictive value from 94.7% (at admission) to 99.4%. Combining the 99th percentile at admission with serial changes in troponin increases the positive predictive value to rule in acute coronary syndrome from 75.1% at admission to 95.8% after 3h. The 2015 ESC Guidelines recommend the use of a rapid rule out protocol (0h and 1h) when hs-cTnI with a validated 0 to1h algorithm is available. Training and displaying the clinical algorithm depicting the role of hs-TnI assay in acute cardiac care units and in EDs are an efficient way to deliver the new standard of care to patients. Compared with contemporary troponin assays, the hs-cTn assay accelerates the diagnostic pathway to 0-1h, thus reducing the time for diagnosis of NSTEMI and hence, its management.
authors.affiliation: Director, Cardiac Sciences, Kokilaben Hospital, Mumbai, India. Electronic address: jjdalal@hotmail.com.
authors.forename: Jamshed J
authors.initials: JJ
authors.lastname: Dalal
authors.affiliation: Interventional Cardiologist, PD Hinduja Hospital, Mumbai, India.
authors.forename: C K
authors.initials: CK
authors.lastname: Ponde
authors.affiliation: Chief of Cardiology and Director of the Cardiac Catherisation Laboratory, Holy Family Hospital, Mumbai, India.
authors.forename: Brian
authors.initials: B
authors.lastname: Pinto
authors.affiliation: Director, Department of Laboratory Medicine, Transplantation Immunology and Molecular Laboratory, MIOT Hospital, Chennai, India.
authors.forename: C N
authors.initials: CN
authors.lastname: Srinivas
authors.affiliation: Chief Cardiologist and Chief Electrophysiologist, Frontier Lifeline Hospital, Chennai, India.
authors.forename: Joy
authors.initials: J
authors.lastname: Thomas
authors.affiliation: Interventional Cardiologist, Indraprastha Apollo Hospitals, Delhi, India.
authors.forename: Sunil Kumar
authors.initials: SK
authors.lastname: Modi
authors.affiliation: Consultant, Emergency Medicine, Kokilaben Dhirubhai Ambani Hospital, Mumbai, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Mehta
authors.affiliation: Laboratory Head, Dr. L H Hiranandani Hospital, Mumbai, India.
authors.forename: Suvin
authors.initials: S
authors.lastname: Shetty
authors.affiliation: Senior Specialist and Head of the Department of Cardiology, Indira Gandhi Government General Hospital and Postgraduate Institute, Pondicherry, India.
authors.lastname: Manimarane
authors.affiliation: Consultant Cardiologist, Dr. Balabhai Nanavati Hospital, Holy Family Hospital, Mumbai, India.
authors.forename: Bhupen
authors.initials: B
authors.lastname: Desai
mesh_terms: D054058:Acute Coronary Syndrome / Q000097:blood / Q000175:diagnosis*; D000465:Algorithms; D015415:Biomarkers / Q000097:blood; D006801:Humans; D019210:Troponin I / Q000097:blood*; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D019210:Troponin I; D020107:Troponin T
keywords: ACS; Biomarkers; STEMI; Troponin; hs Troponin