Imaging Pearls ❯ Vascular ❯ Aortic valves and aortic root
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- “ After aortic root surgery, findings can be categorized as complications within the aorta, complications outside the aorta, and benign postoperative changes. Distinction of normal findings from postoperative complications requires proper CT technique and an understanding of CT findings that require intervention.”
MDCT Evaluation of Aortic Root Surgical Complications
Chu LC, Johnson PT, Cameron DE, Fishman EK
AJR 2013; 201:736-744 - “ Although the expected mortality rate in elective aortic root repair is less than 5%, patients who undergo aortic root repair are at risk of developing early and late term postoperative complications.”
MDCT Evaluation of Aortic Root Surgical Complications
Chu LC, Johnson PT, Cameron DE, Fishman EK
AJR 2013; 201:736-744 - CT Aortic Root Protocol
- Optimally a gated acquisition
- Scan protocol similar to coronary artery protocol and bolus tracking in proximal descending aorta or above root is ideal (trigger minimum 200 depending on the speed of acquisition) for arterial phase imaging
- Contrast injection rate of 5 cc/sec using 100-120 cc of contrast
- Scan parameters of .75 mm thick sections reconstructed at .5 mm - CT Aortic Root Protocol
- Data must be analyzed using axial, MPR and 3D imaging
- Volume rendering ideal for global visualization
- Non contrast CT may be of use in select cases and occassionally delayed images at 60 seconds will be of value - Aortic Root Surgical Complications
- Complications within the aortic root
- Complications outside the aortic root
- Complications outside the aortic root
- MDCT Evaluation of Aortic Root Surgical Complications
Chu LC, Johnson PT, Cameron DE, Fishman EK
AJR 2013; 201:736-744 - Complications within the aortic root
- Pseudoaneurysm
- True aneurysm
- Dissection
- Endoleak
- Coronary ostial aneurysm - Complications outside the aortic root
- Pulmonary embolism
- Hemothorax
- Mediastinitis
- Sternal dehiscence
- Perigraft seroma - Complications outside the aortic root
- Elephant trunk procedure
- Aortic arch debranching with arterial reimplantaion
- Hyperdense surgical material - Complications within the aortic root
Pseudoaneurysm
- Occurs in less than 0.5% of cases after cardiac surgery
- Mediastinitis and graft infection are the most common risk factors
- Other risk factors are Marfans and Takayasu aortitis, dissection of native aorta or excessive use of biologic glue - Pseudoaneurysm: Facts
- Most common site is at graft anastomosis site, followed by coronary artery anastomosis site
- Patient presentation ranges from acute symptoms (chest pain, heart failure, sepsis) to an incidental finding on followup studies
- Treatment of choice is with aortic graft replacement - Complications within the aortic root
Coronary Artery Ostial Aneurysm
- Aneurysm may develop at coronary artery reimplantation site especially in patients with connective tissue disorders like Marfan Syndrome and Loeys Dietz syndrome
- Management subject of debate with long term consequences still unknown. Current management is usually conservative - Coronary Artery Ostial Aneurysm
- Aneurysm may develop at coronary artery reimplantation site especially in patients with connective tissue disorders like Marfan Syndrome and Loeys Dietz syndrome
- Management subject of debate with long term consequences still unknown. Current management is usually conservative - Complications outside the aortic root
- Pulmonary embolism
- Hemothorax
- Mediastinitis
- Sternal dehiscence
- Perigraft seroma - Complications outside the aortic root
Mediastinitis
- Incidence of 0.4-5% with a mortality rate of 27-50%
- Clinical presentation is fever, chest pain, sepsis
- CT findings may be difficult to distinguish early from normal post-operative change (fluid, gas may remain for days in normal post-op patient) - Complications outside the aortic root
Sternal dehiscence
- Occur in up to 7% of patients
- Risk factors include obesity, lung disease, diabetes, renal disease, steroid use, reoperation
- CT findings include displacement of sternal wires, sternal erosion, or cleft within sternotomy site. Associated mediastinitis may be seen - Complications outside the aortic root
- Elephant trunk procedure
- Aortic arch debranching with arterial reimplantaion
- Hyperdense surgical material - Complications outside the aortic root
- Hyperdense surgical material
- Surgical material like felt strips and felt pledgets have high CT attenuation and can simulate contrast extravasation
- Non-contrast CT can usually be done (or delayed scans) to prevent errors in diagnosis - “ Normal postoperative imaging findings, such as hyperattenuating felt pledgets, prosthetic conduits, and reanastomosis sites, may mimic pathologic processes.”
Ascending Thoracic Aorta: Postoperative Imaging Evaluation
Prescott-Focht JA et al.
RadioGraphics 2013;33:73-85 - “ Postoperative complications seen at CT angiography that require further intervention include pseudoaneurysms, anastomotic stenoses, dissections, and aneurysms.”
Ascending Thoracic Aorta: Postoperative Imaging Evaluation
Prescott-Focht JA et al.
RadioGraphics 2013;33:73-85