Multislice CT is safe and efficient for evaluation of low-risk chest pain

Clinical Question

Is an algorithm using multi-slice coronary computed tomography a safe and effective diagnostic approach for patients with acute chest pain?

Bottom Line

Multi-slice coronary computed tomography (MSCT) effectively diagnoses or excludes coronary disease as the cause of acute chest pain in the majority of patients, reducing time to final diagnosis. (LOE = 1b)

Reference

Goldstein JA, Gallagher MJ, O'Neill WW, et al. A randomized controlled trial of multi-slice coronary computed tomography for evaluation of acute chest pain. J Amer Coll Cardiol 2007;49:863-871.  [PMID:17320744]

Study Design

Randomized controlled trial (nonblinded)

Funding

Foundation

Allocation

Concealed

Setting

Emergency department

Synopsis

MSCT is a technique that provides high resolution views of the coronaries, and has been shown to accurately exclude coronary stenosis in low-risk patients with chest pain. This study compared the safety, efficacy, and efficiency of a diagnostic strategy using MSCT versus standard of care (a nuclear stress test) in low-risk patients presenting to the emergency department with acute chest pain. Patients with objective signs of ischemia or infarction were excluded, as were those with a known ejection fraction of less than 45%, a serum creatinine level greater than 1.5 mg/dL (133 umol/L), a body mass index higher than 39 kg/m2, or arrhythmias. Patients in either group who had normal test results were discharged home, while those with abnormal results on nuclear stress testing or severe disease on MSCT (stenosis > 70%) underwent angiography. In the MSCT group, patients with intermediate or nondiagnostic results underwent nuclear stress testing, and were either discharged or referred for angiography on the basis of the results. Patients were enrolled 24 hours a day. All tests were interpreted by a single blinded observer. The researchers enrolled 203 patients. There was a higher percentage of men in the standard of care (SOC) group (57% vs 43%; P = .05). MSCT results led to exclusion or identification of coronary disease as the cause of chest pain in 76% of patients: 68% of patients had normal scans and were discharged and 8% had severe disease and were referred for angiography. Twenty-four percent of patients had intermediate disease (26% to 70% stenosis) or nondiagnostic scans and underwent stress testing. Of these, 87.5% had negative test results and were discharged. Overall, 89% of MSCT patients were discharged on the basis of noninvasive testing, compared with 95% in the SOC group. Of the patients discharged because of noninvasive test results, 1 patient in the MSCT group and 4 patients in the SOC group were admitted for angiography over the next 6 months, none of whom were found to have obstructive disease. No major adverse events occurred in discharged patients. Eleven patients in the MSCT group underwent invasive angiography during initial evaluation: 8 of the 9 patients with abnormal MSCT results had obstructive disease (> 70%) by angiography; the 2 patients with indeterminate scans and positive stress test results did not have significant disease. Three SOC patients underwent initial invasive testing; significant coronary disease was found in one. Despite the need for additional testing in one fourth of the MSCT patients, the median time to diagnosis was significantly shorter in this group (3.4 hours vs 15.0 hours; P < .001). Although the cost per test was similar, the shorter time to diagnosis led to decreased emergency department cost for the approach using MSCT ($1586 vs $1872). However, with more angiographies performed in the MSCT patients, it is possible that the overall cost of care could have been higher with this approach. The identification of significant disease in more patients in the MSCT group could be due to baseline differences between the 2 groups or to greater sensitivity of this test. Whether this would effect long-term clincial events needs further study.