Is Coronary Computed Tomography Angiography a Resource Sparing Strategy in the Risk Stratification and Evaluation of Acute Chest Pain? Results of a Randomized Controlled Trial

Each year, approximately 6 million U.S. citizens are evaluated for acute chest pain syndromes (ACPSs) and billions of dollars of resources are utilized.1,2 While a large part of this cost is attributable to the expense of hospitalization at the time of index evaluation, 60% of those hospitalized are determined not to have coronary artery disease (CAD) as the underlying factor.3–5 Patients are generally hospitalized for continued evaluation and monitored observation because providers may not feel comfortable in excluding CAD or a myocardial infarction (MI) with the current technologies available to them. As such, the inability to rapidly diagnose MI or underlying CAD as the cause of ACPSs has serious public health and economic consequences. Moreover, considering a reported rate of 2% to 8% for unrecognized acute MI, the risk of malpractice litigation further augments the rate of hospitalization and its associated resource utilization.6 The current emergency department (ED) standard care (SC) for risk stratification of ACPS patients in many institutions includes clinical data, serial electrocardiograms (ECGs), and cardiac biomarkers1,7–9 (Figure 1). The addition of exercise stress testing and echocardiograms to this regimen has been studied, but due to the suboptimal sensitivity of exercise stress testing,10–13 and the significant cost of adding nuclear perfusion studies, neither of these technologies have been adopted routinely in many institutions.11,12 Consequently, the current process for excluding CAD has remained time-consuming and relatively expensive.6,7,14–23 Figure 1 SC risk stratification algorithm for patients presenting with acute chest pain to the emergency department. *Additional testing includes exercise stress test, nuclear perfusion testing, stress echocardiography, transesophageal echocardiography, and/or ... In 2009, researchers demonstrated that coronary computerized tomography angiogram (CCTA) technology (Figure 2) is safe and also quite feasible to perform in the ED chest pain population.12,24,25 Furthermore, computer simulation models including CCTA in chest pain patient evaluation demonstrated a marginal association with improved quality-adjusted longevity, raised cost-effectiveness ratios, and illustrated the need for controlled trials to be executed to guide policy.26,27 Figure 2 Axial image obtained using the 64-slice Toshiba CT scanner for this SC + CCTA versus SC-only resource utilization trial at the level of the aortic root showing the origins of the right and left coronary arteries. CCTA = coronary computerized tomography ... To date, there have been no published randomized controlled clinical trials addressing the primary aim of quantifying the resource utilization of adding CCTA to the current SC in the ED evaluation of ACPS patients. We posited that adding a CCTA to the SC (SC + CCTA) in patients with low- to intermediate-risk ACPS would be associated with lower total resource utilization in the 90-day follow-up period after the index ED visit. Accordingly we performed a prospective randomized controlled trial examining the resource utilization with and without the addition of CCTA to the risk stratification of ACPS patients presenting to the ED.