Cost-effectiveness of early noninvasive cardiac testing for suspected acute coronary syndrome.

Background: Early noninvasive cardiac testing (NIT) is often performed in the initial workup of patients who present to the emergency department (ED) with suspected acute coronary syndrome (ACS). Our study objective was to calculate the cost-effectiveness of adopting early NIT for risk stratification to avoid future nonfatal acute myocardial infarction (MI) or death.

Methods: To obtain the incremental difference in cost and clinical outcomes, we first conducted a multicenter retrospective cohort study within the member population of the Kaiser Permanente Southern California integrated health care delivery system. We then adapted existing cost effectiveness models to generate long-term costs and quality-adjusted life-years (QALYs) gained by NIT.

Results: The cohort included 89,387 patients (mean age 57 years, 58% female) and 19% received early NIT. Total cost was higher by $2357 (95% confidence interval [CI] $77 to $4821) for early NIT compared to no early NIT and was mainly due to the increased cost of the index ED visit. Early NIT was associated with lower composite risk of death/nonfatal MI (absolute risk difference -3.7%, 95% CI -4.4% to -3.01%) during a 1-year follow-up. From a payor's perspective, early NIT was cost-effective at $5268/QALYs.

Conclusions: In patients with suspected ACS evaluated in the ED, incorporation of early NIT was associated with an overall increase in cost of health care that was driven by increased cost of the initial ED visit. However, due to the significant clinical benefits, early NIT was cost-effective in the low- and intermediate-risk patients while it is a dominant strategy in high-risk patients saving cost and QALYs.