Early rule-out alogrithm for MI patients proves safe and effective

Implementation of an early indicator for ruling out myocardial infarction (MI) in patients with suspected acute coronary syndrome (ACS), incorporating a single high-sensitivity cardiac troponin (hs-cTn) test at presentation with risk stratification and diagnostic thresholds, is both effective and safe.

The HiSTORIC trial was a stepped-wedge cluster randomised controlled trial conducted in 7 hospitals across Scotland. Randomisation was performed at the hospital level and not per patient; this resulted in enrolment of all consecutive patients undergoing hs-cTnI testing for suspected ACS in the emergency room. MI was ruled out if hs-cTnI concentrations were <5 ng/L at presentation or between 5 ng/L and the 99thcentile with a change <3 ng/L at3hours (High-STEACS pathway). Co-primary endpoints of the study were length of stay (efficacy) and MI or cardiac death after discharge (safety) within 1 year of follow-up. A total of 31,492 patients with cTnI concentrations <99th centile participated. Results demonstrated that the use of this algorithm reduced the length of stay by >3 hours (from 10.1 to 6.8hours;P<0.001). Also, the relative number of patients discharged from the emergency room increased from 53% to 74% (P<0.001).The event rate for the safety outcome measure was similar before and after implementation of the early rule-out algorithm (respectively, 0.4% and 0.3% at 30 days, and 2.7% and 1.8% at 1year). Interestingly, the rate of adherence to the pathway was between 86%-92% for three pre-specified adherence measures. Thus, the HiSTORIC study provided the first randomised controlled trial evidence that a single hs-cTn test can be used to safely and effectively rule out MI at presentation[1].

1. Mills NL. HiSTORIC -High-Sensitivity cardiac Troponin On presentation to Rule out myocardial InfarCtion: A stepped-wedge cluster randomised controlled trial. Abstract 2309.ESC Congress 2019, 31 Aug-4 Sept, Paris, France.



Posted on 10 October 2019