Prior studies comparing US, CT, and MRI of the abdominal aorta found that US is a reliable method to diagnose and follow AAAs [56]. In the evaluation of thoracoabdominal aortic dissection, US can also be used to evaluate blood flow in the true and false lumens and to directly and dynamically monitor the motion of dissection flaps [43]. As such, abdomen US can be performed serially to evaluate for aortic size changes or dissection hemodynamic changes. However, a limited ability to evaluate the thoracic aorta due to difficult acoustic windows could result in poor image quality or the inability to view changes to the aorta. US Echocardiography Transthoracic Resting Transthoracic echocardiogram (TTE) allows visualization of the heart and portions of the thoracic aorta. TTE can be used to evaluate the heart for complications such as pericardial effusion in patients with new symptoms [57]. However, portions of the proximal descending thoracic aorta may be poorly visualized with TTE because of patient acoustic windows and habitus, creating the possibility of false-negative examinations in patients with new symptoms [58]. These characteristics have resulted in a low sensitivity of 31% to 55% for the diagnosis of acute type B aortic dissection on TTE [33]. TTE is also limited by the ability to visualize the abdominal aorta to determine the extent of thoracoabdominal aortic pathology. Variant 2: Planning for endovascular or open repair of thoracoabdominal aorta aneurysm or dissection. Aortography Chest Abdomen Pelvis There is no relevant literature regarding aortography for the planning of thoracoabdominal aortic endovascular or open repair. Aortogram with DSA for evaluation of the thoracic and abdominal aorta has a sensitivity of up to 90% and a specificity of 95% for acute aortic syndrome [27]. The role of aortography before endovascular or open repair is limited to noninvasive modalities such as CTA and MRA.
Thoracoabdominal Aneurysm or Dissection Treatment Planning and Follow Up. Prior studies comparing US, CT, and MRI of the abdominal aorta found that US is a reliable method to diagnose and follow AAAs [56]. In the evaluation of thoracoabdominal aortic dissection, US can also be used to evaluate blood flow in the true and false lumens and to directly and dynamically monitor the motion of dissection flaps [43]. As such, abdomen US can be performed serially to evaluate for aortic size changes or dissection hemodynamic changes. However, a limited ability to evaluate the thoracic aorta due to difficult acoustic windows could result in poor image quality or the inability to view changes to the aorta. US Echocardiography Transthoracic Resting Transthoracic echocardiogram (TTE) allows visualization of the heart and portions of the thoracic aorta. TTE can be used to evaluate the heart for complications such as pericardial effusion in patients with new symptoms [57]. However, portions of the proximal descending thoracic aorta may be poorly visualized with TTE because of patient acoustic windows and habitus, creating the possibility of false-negative examinations in patients with new symptoms [58]. These characteristics have resulted in a low sensitivity of 31% to 55% for the diagnosis of acute type B aortic dissection on TTE [33]. TTE is also limited by the ability to visualize the abdominal aorta to determine the extent of thoracoabdominal aortic pathology. Variant 2: Planning for endovascular or open repair of thoracoabdominal aorta aneurysm or dissection. Aortography Chest Abdomen Pelvis There is no relevant literature regarding aortography for the planning of thoracoabdominal aortic endovascular or open repair. Aortogram with DSA for evaluation of the thoracic and abdominal aorta has a sensitivity of up to 90% and a specificity of 95% for acute aortic syndrome [27]. The role of aortography before endovascular or open repair is limited to noninvasive modalities such as CTA and MRA.