The diagnostic accuracy of digital subtraction angiography approaches 98% in some series for identification of an AD. Angiography permits management of patients who are critically ill and can also assess aortic regurgitation and aortic branch vessel involvement (including the coronary arteries) [14]. High frame rates facilitate identification of the intimal tear and the degree of aortic insufficiency. False-negative arteriograms may occur when the false lumen is not opacified, when there is simultaneous opacification of the true and false lumen, and when the intimal flap is not displayed in profile. Disadvantages of angiography include the fact that it is invasive, requires iodinated contrast material, and that it has a limited ability to assess the surrounding structures (eg, presence of mediastinal hemorrhage), which is readily detected by other cross-sectional imaging modalities [1,3]. CT Chest Without IV Contrast CT chest without intravenous (IV) contrast cannot assess the lumen of that aorta, but AAS can be inferred by identifying displaced aortic calcifications or IMHs, findings that are shown to be 94% and 71% sensitive for diagnosing AAS when using contrast-enhanced CTA as the reference standard [15]. Another study found that abnormal aortic wall contour and paraaortic hematoma were also predictive of AAS. These imaging findings were incorporated into a decision-rule that predicted the presence of AAS with a mean sensitivity of 93% [16]. However, few patients in the derivation data set had PAU as a diagnosis, and the number of patients with AAS in the validation data set was not reported. CT without IV contrast can identify complications from AAS, such as mediastinal, pericardial, and/or pleural hematoma. CT Chest With IV Contrast CT chest with IV contrast can identify the presence of an AAS and the presence of complications such as mediastinal, pericardial, and/or pleural hematoma.
Suspected Acute Aortic Syndrome. The diagnostic accuracy of digital subtraction angiography approaches 98% in some series for identification of an AD. Angiography permits management of patients who are critically ill and can also assess aortic regurgitation and aortic branch vessel involvement (including the coronary arteries) [14]. High frame rates facilitate identification of the intimal tear and the degree of aortic insufficiency. False-negative arteriograms may occur when the false lumen is not opacified, when there is simultaneous opacification of the true and false lumen, and when the intimal flap is not displayed in profile. Disadvantages of angiography include the fact that it is invasive, requires iodinated contrast material, and that it has a limited ability to assess the surrounding structures (eg, presence of mediastinal hemorrhage), which is readily detected by other cross-sectional imaging modalities [1,3]. CT Chest Without IV Contrast CT chest without intravenous (IV) contrast cannot assess the lumen of that aorta, but AAS can be inferred by identifying displaced aortic calcifications or IMHs, findings that are shown to be 94% and 71% sensitive for diagnosing AAS when using contrast-enhanced CTA as the reference standard [15]. Another study found that abnormal aortic wall contour and paraaortic hematoma were also predictive of AAS. These imaging findings were incorporated into a decision-rule that predicted the presence of AAS with a mean sensitivity of 93% [16]. However, few patients in the derivation data set had PAU as a diagnosis, and the number of patients with AAS in the validation data set was not reported. CT without IV contrast can identify complications from AAS, such as mediastinal, pericardial, and/or pleural hematoma. CT Chest With IV Contrast CT chest with IV contrast can identify the presence of an AAS and the presence of complications such as mediastinal, pericardial, and/or pleural hematoma.