An economic analysis of an aggressive diagnostic strategy with single photon emission computed tomography myocardial perfusion imaging and early exercise stress testing in emergency department patients who present with chestpain but nondiagnostic electrocardiograms: Results from a randomized trial

Study objective: Conventional emergency department testing strategies for p atients with chest pain often do not provide unequivocal diagnosis of acute coronary syndromes. This study was conducted to determine whether the rout ine use of single photon emission computed tomography (SPECT) imaging at re st and early exercise stress testing to assess intermediate-risk patients w ith chest pain and no ECG evidence of acute ischemia will lead to earlier d ischarges, more discriminate use of coronary angiography, and an overall re duction in average costs of care with no adverse clinical outcomes. Methods: All patients in this study had technetium Tc-99m tetrofosmin SPECT imaging at rest and were randomly assigned to either a conventional (resul ts of the imaging test blinded to the physician) or perfusion imaging-guide d (results of the imaging lest unblinded to the physician) strategy. Patien ts in the conventional arm were treated at their physician's discretion. Pa tients in the perfusion imaging-guided arm were treated according to a pred efined protocol based on SPECT imaging test results: coronary angiography a fter a positive scan result and exercise treadmill testing after a negative scan result. Study endpoints consisted of total in-hospital costs and leng th of stay. Hospital costs were calculated using hospital department-specif ic Medicare cost/charge ratios. Length of stay was calculated as total hosp ital room days billed (regular and intensive care). Results: We enrolled 46 patients, 9 with acute myocardial infarctions. Pati ents randomly assigned to the perfusion imaging-guided arm had $1,843 (95% confidence interval [CI] $431 to $6,171) lower median in-hospital costs and 2.0-day (95% CI 1.0 to 3.0 days) shorter median lengths of stay but simila r rates of in-hospital and 30-day follow up events as patients in the conve ntional arm. Conclusion: An ED chest pain diagnostic strategy incorporating acute restin g Tc-99m tetrofosmin SPECT imaging and early exercise stress testing may le ad to reduced in-hospital costs and decreased length of stay for patients w ith acute chest pain and nondiagnostic ECGs.