High-sensitivity versus conventional troponin in the emergency department for the diagnosis of acute myocardial infarction
1 Department of Emergency Medicine and Surgery, Hôpital Pitié-Salpétrière, Assistance Publique-Hôpitaux de Paris (APHP), Université Pierre et Marie Curie-Paris 6 (UPMC), 47-83 boulevard de l'hôpital, F-75651 Paris cedex 13, France
2 Department of Biochemistry, Hôpital Cochin-Hôtel Dieu, APHP, 27 rue du Faubourg Saint-Jacques, F-75679 Paris cedex 14, France
3 Department of Emergency Medicine, Hôpital Cochin-Hôtel Dieu, APHP, Université Paris Descartes-Paris 5, 27 rue du Faubourg Saint-Jacques, F-75679 Paris cedex 14, France
4 Department of Emergency, Hôpital Bichat, APHP, 46 rue Henri Huchard, F-75018, Paris, France
5 Department of Biochemistry, Hôpital Bicêtre, APHP, 78 rue du Général Leclerc 94270, Le Kremlin-Bicêtre, France
6 INSERM UMRS 956, UPMC, 91 Boulevard de l'Hôpital, F-75013 Paris, France
Critical Care 2011, 15:R147 doi:10.1186/cc10270Published: 10 June 2011
Recently, newer assays for cardiac troponin (cTn) have been developed which are able to detect changes in concentration of the biomarker at or below the 99th percentile for a normal population. The objective of this study was to compare the diagnostic performance of a new high-sensitivity troponin T (HsTnT) assay to that of conventional cTnI for the diagnosis of acute myocardial infarction (AMI) according to pretest probability (PTP).
In consecutive patients who presented to our emergency departments with chest pain suggestive of AMI, levels of HsTnT were measured at presentation, blinded to the emergency physicians, who were asked to estimate the empirical PTP of AMI. The discharge diagnosis was adjudicated by two independent experts on the basis of all available data.
A total of 317 patients were included, comprising 149 (47%) who were considered to have low PTP, 109 (34%) who were considered to have moderate PTP and 59 (19%) who were considered to have high PTP. AMI was confirmed in 45 patients (14%), 22 (9%) of whom were considered to have low to moderate PTP and 23 (39%) of whom were considered to have high PTP (P < 0.001). In the low to moderate PTP group, HsTnT levels ≥ 0.014 μg/L identified AMI with a higher sensitivity than cTnI (91%, 95% confidence interval (95% CI) 79 to 100, vs. 77% (95% CI 60 to 95); P = 0.001), but the negative predictive value was not different (99% (95% CI 98 to 100) vs. 98% (95% CI 96 to 100)). There was no difference in area under the receiver operating characteristic (ROC) curve between HsTnT and cTnI (0.93 (95% CI 0.90 to 0.98) vs. 0.94 (95% CI 0.88 to 0.97), respectively).
In patients with low to moderate PTP of AMI, HsTnT is slightly more useful than cTnI. Our results confirm that the use of HsTnT has a higher sensitivity than conventional cTnI.