A laboratory score at presentation to rule-out serious cardiac outcomes or death in patients presenting with symptoms suggestive of acute coronary syndrome

Peter A Kavsak; Colleen Shortt; Jinhui Ma; Natasha Clayton; Jonathan Sherbino; Stephen A Hill; Matthew McQueen; Shamir R Mehta; P J Devereaux; Andrew Worster

doi:10.1016/j.cca.2017.03.021

A laboratory score at presentation to rule-out serious cardiac outcomes or death in patients presenting with symptoms suggestive of acute coronary syndrome

Clin Chim Acta. 2017 Jun:469:69-74. doi: 10.1016/j.cca.2017.03.021. Epub 2017 Mar 23.

Authors

Affiliations

¹ Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada. Electronic address: kavsakp@mcmaster.ca.
² Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada.
³ School of Epidemiology, Public Health and Preventive Medicine, University of Ottawa, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada.
⁴ Department of Medicine, McMaster University, Hamilton, ON, Canada.
⁵ Division of Emergency Medicine, McMaster University, Hamilton, ON, Canada.
⁶ Division of Cardiology and Population Health Research Institute, McMaster University, Hamilton, ON, Canada.

PMID: 28342713
DOI: 10.1016/j.cca.2017.03.021

Abstract

Background: We evaluated whether a low high-sensitivity cardiac troponin (hs-cTn) cutoff combined with glucose, red cell distribution width (RDW), and the estimated glomerular filtration rate (eGFR) can be used to rule-out a serious cardiac outcome or death in patients presenting with symptoms suggestive of acute coronary syndrome (ACS).

Methods: This was a prospective observational emergency department (ED) study enrolling consecutive patients presenting with symptoms suggestive of ACS (ClinicalTrials.gov: NCT01994577). The primary outcome was a 7-day composite of myocardial infarction, unstable angina, decompensated congestive heart failure, serious ventricular cardiac arrhythmia, or death. A laboratory score combining glucose, RDW, eGFR with hs-cTnT (Roche) or hs-cTnI (Abbott) was compared to hs-cTn alone using the limit of detection (LoD; hs-cTnT<5ng/l/hs-cTnI<2ng/l) as the cutoff. A benchmark of >99% sensitivity was used to assess the laboratory panel with hs-cTn versus the LoD alone to identify low-risk patients suitable for discharge.

Results: A total of 1095 patients (n=267 composite-outcomes) had measurements of glucose, RDW, eGFR, hs-cTnT, and hs-cTnI at presentation. Applying the hs-cTn LoD alone as the cutoff missed 5 composite-outcomes (sensitivity=98.1%), however the addition of the laboratory panel to the hs-cTn LoD increased the sensitivity to >99% with approximately 10% of the population identified as low-risk. The percentage of low-risk patients was increased to 15% (1 composite-outcome missed) when employing a low measurable hs-cTnI cutoff with the laboratory panel (laboratory score<2 points).

Conclusion: A laboratory score with hs-cTn may identify low-risk patients suitable for ED discharge at presentation.

Keywords: Acute coronary syndrome; Death; Emergency department; Heart failure; High-sensitivity cardiac troponin; Myocardial infarction; Rule-out.

Publication types

Clinical Trial

MeSH terms

Acute Coronary Syndrome / blood
Acute Coronary Syndrome / diagnosis*
Acute Coronary Syndrome / metabolism
Acute Coronary Syndrome / physiopathology
Adult
Blood Glucose / metabolism
Clinical Laboratory Techniques*
Death
Emergency Service, Hospital
Erythrocyte Count
Glomerular Filtration Rate
Humans
Myocardium / metabolism*
Prognosis
Troponin / metabolism

Substances

Blood Glucose
Troponin

Associated data

ClinicalTrials.gov/NCT01994577