The utility of risk scores when evaluating for acute myocardial infarction using high-sensitivity cardiac troponin I.

UNLABELLED

Risk scores including the Thrombolysis in Myocardial Infarction (TIMI) score; History, Electrocardiogram, Age, Risk Factors, and Troponin (HEART) score; and Simplified Emergency Department Assessment of Chest Pain Score (sEDACS) have been used to evaluate patients with symptoms suggestive of acute myocardial infarct (AMI). This study assessed prognostic utility of cardiac risk stratification scores when augmented with a high-sensitivity cardiac troponin-I assay (hs-cTnI).

METHODS

This study enrolled 2,505 suspected AMI patients at 29 hospitals in the United States from April 2015 to April 2016. Blood samples were tested for hs-cTnI on the Atellica IM TnIH Assay (Siemens Healthineers). Patients were considered low risk for death/AMI with a TIMI score = 0, HEART ≤3, sEDACS ≤15, and hs-cTnI <45 ng/L (99th percentile) at time 0 and 2-3 hours.

RESULTS

There were 2,336 patients included after exclusions for ST-segment elevation myocardial infarction or incomplete data. At 30 days, 283 patients (12.1%) had been diagnosed with AMI, and there were 24 (1.0%) deaths and 213 (9.1%) revascularizations. Of 298 patients with death or AMI, 258 (86.6%) had elevated hs-cTnI. The HEART score and sEDACS identified 34.5% and 36.6% of patients as low risk, respectively. This was significantly more than the 12.1% identified by the TIMI score (P < .01).

CONCLUSIONS

The TIMI, HEART, and sEDACS scores all identify low-risk patients when combined with hs-cTnI measurements. The HEART score and sEDACS identified more low-risk patients compared to the TIMI score. These patients could be considered for discharge from the emergency department without further testing.