Comparison of new point-of-care troponin assay with high sensitivity troponin in diagnosing myocardial infarction.

Abstract

OBJECTIVES:

The aim of this study is to compare a new improved point of care cardiac troponin assay (new POC-cTnI) with 1. its predecessor (old POC-cTnI) and 2. a high sensitivity assay (hs-cTnI) for the diagnosis of acute myocardial infarction (AMI) and for major adverse cardiac events (MACE) by 30 days.

METHODS:

This is a single centre observational study, set in Christchurch Hospital, New Zealand. Patients presenting to the emergency department with non-traumatic chest pain underwent blood sampling at 0 h and 2h post presentation for analysis with the 3 cTnI assays for the outcome of AMI and for analysis using an accelerated diagnostic protocol (ADP-normal 2h troponins, normal electrocardiograms and Thrombolysis In Myocardial Infarction (TIMI) score of 0 or ≤ 1) for 30 day MACE.

RESULTS:

Of 962 patients, 220 (22.9%) had AMI. Old POC-cTnI was least sensitive at 70.0% (65.4-73.9%) by 2h (p<0.001). New POC-cTnI, sensitivity 93.6% (89.9-96.2%) had similar sensitivity to hs-cTnI, sensitivity 95.0% (91.5-97.3%) (p = 0.508). There were 231 (24.0%) patients with 30 day MACE. When used as part of the ADP, all assays had 100% (98.0-100%) sensitivity using TIMI = 0. Sensitivities of new POC-cTnI ADP, 98.3% (95.4-99.4%), old POC-cTnI, 96.5% (93.2-98.4%) and hs-cTnI, 98.7% (96.0-99.7%) were similar (p = 0.063-0.375) using TIMI ≤ 1.

CONCLUSIONS:

A new POC-cTnI has improved sensitivity for AMI and MACE compared with its predecessor and comparable sensitivity to a high sensitivity assay. Now that sensitivities of the POC assay are improved, the new assay may be a useful alternative to central laboratory assays when rapid turn-around times are not possible.

• Authors: Sally Aldous, A Mark Richards, Peter M George, Louise Cullen, William A Parsonage, Dylan Flaws, Christopher M Florkowski, Richard W Troughton, Jack W O'Sullivan, Christopher M Reid, Laura Bannister, Martin Than
• Journal: International journal of cardiology (Int J Cardiol) Vol. 177 Issue 1 Pg. 182-6 (Nov 15 2014) ISSN: 1874-1754 [Electronic] Netherlands
• PMID: 25499373 (Publication Type: Journal Article, Observational Study, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Chemical References

• Biomarkers
• Troponin

Topics

• Aged
• Biomarkers (blood)
• Diagnosis, Differential
• Female
• Follow-Up Studies
• Humans
• Male
• Middle Aged
• Myocardial Infarction (blood, diagnosis)
• Point-of-Care Systems
• Prognosis
• ROC Curve
• Reproducibility of Results
• Retrospective Studies
• Troponin (blood)