Differences in cardiac testing resource utilization using two different risk stratification schemes.

OBJECTIVE: Assess whether changing an emergency department (ED) chest pain pathway from utilizing the Thrombolysis in Myocardial Infarction (TIMI) score for risk stratification to an approach utilizing the History, EKG, Age, Risk, Troponin (HEART) score was associated with reductions in healthcare resource utilization. METHODS: A retrospective, quasi-experimental study using difference-in-differences and interrupted time series specifications evaluated all ED patients with a chest pain encounter from 8/2015 to 7/2019 at a large academic medical center. We included patients age ≥ 18 with negative troponin testing discharged from the ED. Our standardized care pathway utilized TIMI for risk stratification until 09/2017 and HEART thereafter. We evaluated patients undergoing hospital-based cardiac diagnostic testing (CDT), length of stay (LOS), and 30-day Major Adverse Cardiovascular Events (MACE) at the intervention site before and after the pathway change and compared these outcomes to a similar control site within the health system for the difference-in-differences specification. RESULTS: During the study period, 6.3% (450 of 7117) of patients in the TIMI cohort and 7.2% (546 of 7623) in the HEART cohort among 400,965 total ED visits underwent CDT. In a multivariable analysis, transition to the HEART pathway was associated with greater odds of receiving CDT (odds ratio 2.88 [95% CI 1.21 to 6.86]), a reduction in LOS of 34 min (95% CI 2.2 to 67.6), and no significant difference in 30-day MACE. CONCLUSION: The transition from TIMI to HEART was associated with mixed consequences for healthcare resource utilization, including increased CDT but reduced length of stay.