الفهرس 
Anatomy of the Coronaries and Great Thoracic VesselsOnly 14 pages are availabe for public view
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Abstract
Given the robust clinical performance of CCTA for exclusion of acute coronary syndrome in emergency department patients, as well as the widespread use and proven clinical accuracy of ct angiography for diagnosis of acute aortic dissection (Willoteaux et al., 2008; Shiga et al., 2006), and pulmonary embolism (Ghaye et al., 2002; Quiroz et al., 2005).
A ”triple rule out” scan protocol to simultaneously exclude all three potentially fatal causes of acute chest pain with a single scan is an attractive option.
A conventional cardiac CTA ”field of view” includes the anatomy between the carina and the diaphragm.
A ”triple rule out” scan protocol involves coverage of the entire lung from apices to diaphragm.
Well over 50%of acute chest pain cases represent non cardiac conditions for patients with acute chest pain presented with a non cardiac condition (Gallagher et al., 2008).
Images of thoracic and non cardiac findings are obtained as a ”by-product” available to the expert reader.
The wider anatomical coverage during the ”triple rule out” scan allows images of these findings to be obtained.
Diseases that can be detected include pericardial thickening and/or effusions, esophageal pathology, pneumonia, pulmonary nodules, pneumothoraces, mediastinal masses, pleural effusions and masses, as well as chest wall abnormalities (Onuma et al., 2006).
So in emergency department patients with atypical chest pain and low to intermediate risk, the triple rule out protocol may be preferred, especially in older patients who have relatively lower risk of lifelong radiation induced cancer.
However, the increased radiation dose resulting from the extended volume coverage with this protocol should be fully considered prior to performing this protocol.
Therefore, in emergency department patients who have a low clinical suspicion of pulmonary embolism and acute aortic syndrome, especially younger patients, dedicated coronary CT angiography accompanied by modifications to reduce dose is recommended (Smith et al., 2007).