High-Sensitivity Troponin Testing May Not Alter Outcomes in Chest Pain

High-sensitivity troponin testing alone may not alter care or outcomes among patients with chest pain who present to emergency departments, according to research published in Circulation: Cardiovascular Quality and Outcomes.

Derek P. Chew, MBBS, MPH, of Flinders University in Adelaide, Australia, and colleagues conducted a randomized study to examine effects of troponin reporting on patient care and outcomes. The primary end point was death and new or recurrent acute coronary syndrome (ACS) by 12 months.

As the authors noted, more precise troponin assays have been recently developed, but there may be risks associated with “overinvestigating” patients with elevated troponin levels unrelated to ACS.  

A total of 1937 patients without ST-segment elevation were included in the study (median age: 61; 46.3% women). Maximal troponin <30 ng/L within 24 hours of index hospitalization was reported in 1466 patients. Researchers found that randomization to high-sensitivity report format did not change the admission rate (high-sensitivity report: 57.7% vs standard report: 58.0%; P=.069).

High-sensitivity reporting did not reduce the primary end point compared with standard reporting (9.7% vs 7.2%, respectively; hazard ratio [HR]: 0.83; 95% confidence interval [CI]: 0.57-1.22; P=.362), although a modest reduction was seen in patients with troponin levels <30 ng/L (2.6% vs 4.4%, respectively; HR: 0.58; 95% CI: 0.34-0.10; P=.05).

In terms of hospital discharge, there was no difference in the proportion of patients discharged directly from the emergency department to home with high-sensitivity reporting vs standard reporting (41.8% vs 40.1%, respectively; P=.514). There was, however, a higher rate of discharge among patients in the high-sensitivity report group who were classified as low or no risk by Heart Foundation Criteria, compared with the standard report group (66.4% vs 56.3%, respectively; P=.01).

Dr Chew and colleagues also noted a nonsignificant increase in coronary angiography among patients in the high-sensitivity group, with a nonsignificant increase in revascularization by 12 months. Both groups received antiplatelet and statin therapy at the same frequency. Interestingly, a significant interaction was seen between aspirin and statin prescriptions and high-sensitivity report use compared with the standard report (aspirin: 55.4% vs 34.0%, respectively; P=.006; interaction P=.007 and statins: 65.6% vs 5.0%, respectively; P=.017; interaction P=.005).

“Given the limited impact on care, the modest reduction in recurrent cardiac events and mortality should be interpreted with caution, especially considering the multiple comparisons and the lack of difference seen for the primary outcome analysis,” the authors concluded. “Nevertheless, subtle differences in practice, particularly among patients with other noncoronary cardiac conditions, may account for differences in outcomes observed.”

They added that testing protocols need to be validated in similar trials in order to achieve the full benefit in clinical practice.

Reference

Chew DP, Zeitz C, Worthley M, et al. Randomized comparison of high-sensitivity troponin reporting in undifferentiated chest pain assessment. Circ Cardiovasc Qual Outcomes. 2016;9. doi: 10.1161/CIRCOUTCOMES.115.002488.