Radiology: Volume 260: Number 2-August 2011
Arthur Nasis, MBBS, FRACP Ian T. Meredith, MBBS, PhD, FRACP Nitesh Nerlekar, MBBS James D. Cameron, MBBS, MD Paul R. Antonis, MBBS, FRACP Philip M. Mottram, MBBS, PhD, FRACP Michael C. Leung, MBBS, PhD, FRACP John M. Troupis, MBBS, FRANCR Marcus Crossett, BAppSci Anthony G. Kambourakis, MBBS, FACEM George Braitberg, MBBS, FACEM Udo Hoffmann, MD, MPH Sujith K. Seneviratne, MBBS, FRACP
Purpose: To assess the impact on length of stay and rate of major adverse cardiovascular events of a cardiac computed tomo¬graphic (CT) angiography-guided algorithm to examine pa¬tients who present to the emergency department (ED) with low- to intermediate-risk chest pain.
Methods and Materials: The study was approved by the institutional review board, and all patients gave written informed consent. Two hun¬dred three consecutive patients (mean age, 55 years ± 11 [standard deviation]; 123 men) with low- to intermediate-risk ischemic-type chest pain were prospectively enrolled. Patients underwent initial cardiac CT angiography with subsequent treatment determined by reference to findings at cardiac CT angiography; patients without overt plaque were immediately discharged from the hospital, patients with nonobstructive plaque and mild-to-moderate stenoses were discharged after a negative 6-hour troponin level, and patients with severe stenoses were admitted to the hospital. Discharged patients were followed up for a mean of 14.2 months. Additionally, length of stay and safety out¬comes among these patients were compared with those in 102 consecutive patients with low- to intermediate-risk chest pain who presented to the ED and underwent a stan¬dard of care (SOC) work-up without cardiac CT angiogra¬phy. One-way analysis of variance with Bonferroni correc¬tion was used to compare length of stay between groups.
Results: Cardiac CT angiography findings in the 203 patients who underwent cardiac CT angiography were as follows: Sixty-five (32%) patients had no plaque, 107 (53%) had nonob¬structive plaque, and 31 (15%) had severe stenoses. At follow-up, there were no deaths or cases of acute coronary syndrome (cardiac CT angiography, 0%, 95% confidence interval [CI]: 0%, 1.85%; SOC, 0%, 95% CI: 0%, 3.63%), and the rate of readmission to the hospital because of chest pain was higher with the SOC approach (9% vs 1%, P = .01). Mean ED length of stay was lower with cardiac CT angiography (6.62 hours ±0.38 after a single troponin level and 9.15 hours ± 0.30 after serial troponin levels) than with the SOC approach (11.62 hours ± 0.47, P < .001).
Conclusion: Tailoring troponin measurement to cardiac CT angiogra¬phy findings is safe and allows early discharge of patients with low- to intermediate-risk chest pain, resulting in re¬duced length of stay.