From the Guidelines
Computed Tomography (CT) is the best method for detecting aortic arch disease.
Key Points
- CT has become the preferred modality for evaluating most patients with suspected aortic arch disease due to its high sensitivity and specificity, wide availability, and quick performance time 1.
- CT can detect the presence and mechanism of aortic branch vessel involvement, vessel patency, signs of malperfusion, pericardial effusion and hemopericardium, periaortic or mediastinal hematoma, and pleural effusion 1.
- The choice of initial imaging modality should be based on the patient’s history and clinical presentation, the specific clinical questions to be answered, and the institutional availability, experience, and expertise with each of the diagnostic imaging techniques 1.
- Electrocardiogram (ECG)-gated acquisition protocols are crucial in reducing motion artefacts of the aortic root and thoracic aorta, and high-end MSCT scanners are preferred for their higher spatial and temporal resolution 1.
- CT angiography has several advantages, including short scan time, the ability to obtain a 3-dimensional data set of the entire aorta, wide availability, and low operator dependence 1.
- Some of the limitations of CT include poor characterization of active inflammation, the risk of iodinated contrast nephropathy, and ionizing radiation 1.
- Other imaging modalities, such as MRI and TEE, may be used in certain clinical circumstances, such as patients with a history of iodinated contrast reaction or those who are too unstable to travel to the radiology suite 1.
From the Research
Detection Methods for Aortic Arch Disease
The detection of aortic arch disease can be achieved through various imaging methods, each with its own advantages and limitations. The choice of method depends on the specific clinical scenario and the availability of resources.
Imaging Modalities
- Magnetic Resonance Angiography (MRA): MRA has been shown to be highly accurate in detecting and grading lesions involving the aortic arch vessels 2. It is a noninvasive method that can be used for screening, treatment planning, and follow-up in known or suspected arterial disease in aortic arch arteries.
- Computed Tomography Angiography (CTA): CTA is a rapid and noninvasive alternative to transesophageal echocardiography (TEE) for evaluating aortic arch disease 3. It has a high negative predictive value for aortic arch atheromas, especially for higher-grade atheromas.
- Transesophageal Echocardiography (TEE): TEE is considered the gold standard for evaluating aortic arch disease 3. However, it has associated risks and may not always be readily available.
- Digital Subtraction Angiography (DSA): DSA is considered the standard of reference for evaluating occlusive disease in the aortic arch vessels 2.
- Cardiac Magnetic Resonance Imaging (cMRI): cMRI is an alternative to echocardiography when acoustic windows are limited 4. It does not use ionizing radiation or nephrotoxic contrast and can evaluate physiology.
Diagnostic Accuracy
- MRA has been shown to have high accuracy in detecting and grading lesions involving the aortic arch vessels, with sensitivity and specificity values of 88.5% and 95.6%, respectively 2.
- CTA has a sensitivity of 53% and specificity of 89% in detecting aortic arch atheromas, with a high negative predictive value of 60% 3.
- TEE is considered the gold standard for evaluating aortic arch disease, but its diagnostic accuracy is not directly compared to other modalities in the provided studies.
Clinical Applications
- MRA can be used for screening, treatment planning, and follow-up in known or suspected arterial disease in aortic arch arteries 2.
- CTA may be a useful screening tool to exclude high-grade plaques, indicating a possible complementary role for CTA in detecting aortic arch atheromas 3.
- cMRI can be used to evaluate physiology and may be an alternative to diagnostic catheterization 4.