Identification of very low-risk acute chest pain patients without troponin testing

Abstract

Background: The HEART Pathway combines a History ECG Age Risk factor (HEAR) score and serial troponins to risk stratify patients with acute chest pain. However, it is unclear whether patients with HEAR scores of <1 require troponin testing. The objective of this study is to measure the major adverse cardiac event (MACE) rate among patients with <1 HEAR scores and determine whether serial troponin testing is needed to achieve a miss rate <1%.

Methods: A secondary analysis of the HEART Pathway Implementation Study was conducted. HEART Pathway risk assessments (HEAR scores and serial troponin testing at 0 and 3 hours) were completed by the providers on adult patients with chest pain from three US sites between November 2014 and January 2016. MACE (composite of death, myocardial infarction (MI) and coronary revascularisation) at 30 days was determined. The proportion of patients with HEAR scores of <1 diagnosed with MACE within 30 days was calculated. The impact of troponin testing on patients with HEAR scores of <1 was determined using Net Reclassification Improvement Index (NRI).

Results: Providers completed HEAR assessments on 4979 patients and HEAR scores<1 occurred in 9.0% (447/4979) of patients. Among these patients, MACE at 30 days occurred in 0.9% (4/447; 95% CI 0.2% to 2.3%) with two deaths, two MIs and 0 revascularisations. The sensitivity and negative predictive value for MACE in the HEAR <1 was 97.8% (95%CI 94.5% to 99.4%) and 99.1% (95% CI 97.7% to 99.8%), respectively, and were not improved by troponin testing. Troponin testing in patients with HEAR <1 correctly reclassified two patients diagnosed with MACE, and was elevated among seven patients without MACE yielding an NRI of 0.9% (95%CI -0.7 to 2.4%).

Conclusion: These data suggest that patients with HEAR scores of 0 and 1 represent a very low-risk group that may not require troponin testing to achieve a missed MACE rate <1%. Trial registration number NCT02056964.

Keywords: ECG; acute coronary syndrome; cardiac care, acute coronary syndrome; cardiac care, acute myocardal infarct; cardiac care, diagnosis.

Conflict of interest statement

Competing interests: SAM receives research funding from Roche Diagnostics, Abbott Point of Care, Ortho Clinical Diagnostics, Creavo Medical Technologies, PCORI, AHRQ and NHLBI (1 R01 HL11826301). He is a consultant for Roche Diagnostics and Amgen. SAM is the chief medical officer for Impathiq. JPS receives research funding from Roche Diagnostics and Abbott Point of Care. LS receives research funding from Forest Devices and the NHLBI (1 R01 HL144624-01). CDM receives research funding from Abbott, Siemens, NHLBI 118263, Creavo Medical Technologies.

© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.

Figures

Figure 1

Participant flow diagram. A total of 4979 patients were accrued in the postimplementation and wash-in periods. A total of 820 patients were excluded for not having HEART pathway assessments. A total of 1170 patients were excluded for being obviously high risk, leaving 3809 patients who were eligible for hear score calculation using the HEART pathway CDS tool. CAD, coronary artery disease; CDS, clinical decision support; HEAR, History ECG Age Risk factor.