Axial Chest CT Aids Identification of Cardiac Chamber Enlargement

Leesburg, VA, October 29, 2018—Although cardiac MRI is considered the reference standard for evaluation of cardiac size and function, it is rarely performed as an initial investigation because of its high cost and limited availability. An article in the November 2018 issue of the American Journal of Roentgenology (AJR) shows that cardiac chamber enlargement can be identified with high specificity and reasonable sensitivity on axial chest CT images by use of sex-specific measurement thresholds.

Cardiac chamber enlargement is important to identify because it can be associated with adverse outcomes and may indicate a potentially treatable underlying pathologic condition. Researchers, led by Kate Hanneman, of the Toronto General Hospital and the University of Toronto, sought to establish sex-specific axial chest CT measurement thresholds to identify cardiac chamber enlargement with cardiac MRI as the reference standard.

The study assessed 217 patients who underwent contrast-enhanced chest CT and cardiac MRI within a seven-day period between August 2006 and August 2016. Measurements were taken on axial CT images to evaluate right atrial (RA), right ventricular (RV), left atrial (LA), and left ventricular (LV) chamber size. The presence of chamber enlargement for all four areas was established using cardiac MRI as a reference.

In men, the prevalence of chamber enlargement was 26 percent for RA, 11 percent for RV, 40 percent for LA and 24 percent for LV. In women, the prevalence for chamber enlargement was 16 percent for RA, 15 percent for RV, 27 percent for LA and 12 percent for LV.

The results showed that cardiac chamber enlargement can be identified with high specificity and reasonable sensitivity at non-gated chest CT by use of simple diameter measurements made on non-reformatted axial images.

Founded in 1900, ARRS is the first and oldest radiology society in the United States, and is an international forum for progress in radiology. The Society's mission is to improve health through a community committed to advancing knowledge and skills in radiology. ARRS achieves its mission through an annual scientific and educational meeting, publication of the American Journal of Roentgenology (AJR) and InPractice magazine, topical symposia and webinars, and print and online educational materials. ARRS is located in Leesburg, VA.