Cardiac CT in Patients With Acute Chest Pain | Points to Remember
- Nieman K, Hoffmann U.
- Cardiac Computed Tomography in Patients With Acute Chest Pain. Eur Heart J 2015;Feb 16:[Epub ahead of print].
This review article summarizes current literature regarding the use of coronary computed tomography angiography (CCTA) in the emergency department (ED). There are seven key points to this article:
- In comparison to invasive angiography, CCTA has a higher sensitivity than other available testing (98-100%), while its specificity is approximately 85% and is comparable to other tests. Radiation doses have significantly decreased, and it can routinely be performed at low radiation doses (typically <5 mSv).
- Several randomized trials have demonstrated the safety of CCTA in low- to intermediate-risk patients with chest pain; among over 3,000 patients studied in three randomized trials of CCTA in the ED, no patients were discharged with a missed acute coronary syndrome diagnosis. In comparison to standard-of-care, CCTA was associated with reduced length of stay and ED costs, but similar total hospital costs, which may be driven by increased rates of invasive angiography and revascularization in patients imaged by CCTA.
- Many patients may not be optimal candidates for CCTA in the ED, including those with known coronary artery disease, arrhythmia or tachycardia, morbid obesity, or contraindication to iodinated contrast. Further, availability of CCTA is limited to times when experienced medical staff and readers are available.
- Ischemia assessment by CT is possible using stress-perfusion imaging or fractional flow reserve derived from computation fluid dynamics. While not discussed in this review article, these approaches remain investigational.
- CCTA is uniquely able to noninvasively define plaque characteristics in a manner similar to intravascular ultrasound. Specific plaque characteristics, such as positive remodeling, low attenuation plaque, high plaque burden, and spotty calcification may identify high-risk coronary plaques, but more study is needed to determine how to manage these findings in clinical practice.
- Existing societal guidelines suggest that CCTA may be appropriate in low- to intermediate-risk patients with nondiagnostic electrocardiograms and cardiac enzymes. It is expected that future guidelines will incorporate data from more recent randomized trials.
- CCTA is a reliable and accurate testing option in lower-risk patients presenting with acute chest pain, although its broad use is limited by the need for specific equipment and high levels of site expertise, as well as current study contraindications.
< Back to Listings