Author + information
- Received February 16, 2011
- Revision received May 26, 2011
- Accepted June 7, 2011
- Published online September 20, 2011.
- Richard Body, MB, ChB, PhD⁎,⁎ (, )
- Simon Carley, MD†,
- Garry McDowell, PhD⁎,
- Allan S. Jaffe, MD‡,
- Michael France, MB BS†,
- Kennedy Cruickshank, MB, MD⁎,
- Christopher Wibberley, PhD§,
- Michelle Nuttall† and
- Kevin Mackway-Jones, BM, BCh, MA†
- ↵⁎Reprints requests and correspondence:
Dr. Richard Body, Cardiovascular Sciences, 3rd Floor, Core Technology Facility, University of Manchester, 46, Grafton Street, Manchester M13 9WL, United Kingdom
Objectives This paper sought to evaluate whether high sensitivity troponin (hs-cTnT) can immediately exclude acute myocardial infarction (AMI) at a novel ‘rule out' cut-off.
Background Subgroup analysis of recent evidence suggests that undetectable hs-cTnT may exclude AMI at presentation.
Methods In a cohort study, we prospectively enrolled patients with chest pain, evaluating them with standard troponin T and testing for hs-cTnT (Roche Diagnostics, Basel, Switzerland) at presentation. The primary outcome was a diagnosis of AMI. We also followed up patients for adverse events within 6 months. After subsequent clinical implementation of hs-cTnT, we again evaluated whether initially undetectable hs-cTnT ruled out a subsequent rise.
Results Of 703 patients in the cohort study, 130 (18.5%) had AMI, none of whom initially had undetectable hs-cTnT (sensitivity: 100.0%, 95% confidence interval [CI]: 95.1% to 100.0%, negative predictive value: 100.0%, 95% CI: 98.1% to 100.0%). This strategy would rule out AMI in 27.7% of patients, 2 (1.0%) of whom died or had AMI within 6 months (1 periprocedural AMI, 1 noncardiac death). We evaluated this approach in an additional 915 patients in clinical practice. Only 1 patient (0.6%) with initially undetectable hs-cTnT had subsequent elevation (to 17 ng/l), giving a sensitivity of 99.8% (95% CI: 99.1% to 100.0%) and a negative predictive value of 99.4% (95% CI: 96.6% to 100.0%).
Conclusions Undetectable hs-cTnT at presentation has very high negative predictive value, which may be considered to rule out AMI, identifying patients at low risk of adverse events. Pending further validation, this strategy may reduce the need for serial testing and empirical treatment, enabling earlier reassurance for patients and fewer unnecessary evaluations and hospital admissions.
- acute coronary syndromes
- acute myocardial infarction
- high sensitivity
- sensitivity and specificity
This study was funded by a grant from Central Manchester NHS Foundation Trust. For the cohort study, reagents for the high sensitivity troponin T assay were donated by Roche Diagnostics. Additional work in this cohort has been undertaken under collaborative agreements with Alere and Randox. All analyses were conducted independently of Roche Diagnostics, and no restrictions were placed on the freedom of the authors to publish the findings of this research. Dr. Body has accepted travel and accommodation without honoraria from Roche Diagnostics and Randox Diagnostics for 2 conferences. Dr. Jaffe has accepted consulting fees/honoraria from most of the major diagnostic companies. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received February 16, 2011.
- Revision received May 26, 2011.
- Accepted June 7, 2011.
- American College of Cardiology Foundation