Utilization and Costs of Noninvasive Cardiac Tests After Acute Coronary Syndromes: Insights From the Alberta COAPT Study

BACKGROUND: Although appropriate noninvasive cardiac tests (NICTs) after an acute coronary syndrome (ACS) provide useful prognostic information, inappropriate use leads to inefficient expenditure of existing healthcare resources. By using the Alberta Contemporary Acute Coronary Syndrome Patient Invasive Treatment Strategies (COAPT) Registry, we evaluated the use and costs of NICTs among patients discharged within 1 year after ACS. METHODS: All patients discharged from the hospital with a primary diagnosis of ACS in Alberta between 2004/2005 and 2015/2016 were included. Frequency of NICTs (stress tests [± imaging] and nonstress imaging tests) was determined from linked provincial databases. Costs were obtained from the Alberta Health Care Insurance Plan Medical Procedure List. RESULTS: Of 55,516 patients with ACS, 30,760 had at least 1 NICT (55.4%), with 13,505 (24.3%) having > 1 NICT performed within 1 year. Temporal trends of NICT increased over time (stress tests: P trend < 0.001; nonstress imaging tests: P trend < 0.001). NICT most commonly occurred within the first 4 months after hospital discharge (stress tests at 2 months; nonstress imaging tests at 3-4 months). In 2015/2016, the total estimated costs of NICT were $1.35M, a 22.4% increase from 2004/2005 (1.10M) (P < 0.001), whereas a decrease in incidence of ACS over the same time period was noted (P = 0.008). CONCLUSIONS: Rates of NICT 1 year after ACS are high and increasing over time. Estimated costs of NICT appear to be escalating out of proportion to the ACS growth. Further investigation is warranted because it is speculative whether the increase in NICT and costs results in clinical benefit after ACS.