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.

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