- Aortic Transection: Facts
- 10-20% of patients survive the initial event
- Occurs most commonly at aortic isthmus (space between brachiocephalic trunk and that of the ligamentum arteriosus)
- Mediastinal hematoma (anterior of posterior mediastinum) is common but not diagnostic of aortic injury
- Hematoma of interest most commonly around the aorta - Aortic Transection: Facts
- The direct signs of aortic transection include;
- Vessel caliber change
- Pseudoaneurysm
- Intramural flap - Cardiac Trauma: Differential Diagnosis
- Aortic transection
- Valvular rupture
- Hemopericardium
- Cardiac tamponade - Hypovolemic Shock: CT Findings
- Bright adrenals
- Diffuse fluid filled dilated small bowel
- Hyperenhancement of the small bowel
- Hyperenhancement of the gall bladder mucosa
- Reduced splenic perfusion
- Intense enhancement of the kidneys
- Peripancreatic edema - CARDIAC TAMPONADE
- Accumulation of pericardial fluid, blood, tumor, or air that increases intrapericardial pressure, restricting cardiac filling, and decreasing cardiac output.
- Cardiac emergency that can be fatal. - CARDIAC TAMPONADE:
ACUTE
- Rapid onset seen in cardiac/great vessel trauma or s/p invasive procedure
- Beck triad: hypotension, jugular venous distention, and distant heart sounds
- Effusion may be small, given the relative inelasticity of the pericardium - CARDIAC TAMPONADE:
SUBACUTE
- More gradual process of fluid accumulation
- Allows for stretching of pericardium and much larger effusions than seen acutely
- The most common type of tamponade seen in malignancy, TB, uremia
- S+S more subtle, some or all of Beck’s triad may be absent - CARDIAC TAMPONADE:
CT FINDINGS
- Enlarged SVC - adjacent thoracic aorta
- Enlarged IVC > 2X adjacent aorta
- Contrast reflux into IVC, azygos vein
- Enlarged hepatic and renal veins - CARDIAC TAMPONADE:
CT FINDINGS
- <0 HU: chylopericardium- CA, infection
- 0-20 HU: simple serous effusion- CHF, renal failure, or non-hemorrhagic CA
- > 20 HU hemopericardium, CA, purulent exudates, or myxedematous effusion
"A right aortic arch can occur in isolation or in association with congenital heart disease, especially in tetralogy of Fallot and truncus arteriosus. Edwards embryologic double aortic arch model can help explain the embryogenesis of many variations of right aortic arch." Right Aortic Arch and Its Variants
Kanne JP, Godwin D
J Cardiovascular Comput Tomogr (2010) 4,293-300 - Double Aortic Arch: Facts
- Most common symptomatic vascular aortic arch
- The right arch is larger , posterior, ad more cephalad than the left arch in two thirds of patients and the descending aorta is usually contralateral to the dominant arch
- Trachea compression is common
- Descending aortic diverticulum (Kommerell) is not uncommon - Aberrant left subclavian artery: facts
- Left subclavian arise as last arch vessel and crosses right to left (patient has right sided arch) and posterior to the esophagus
- Bulblike dilatation of abberrant subclavian can occur and is called diverticulum of Kommerell
- When large the diverticulum of Kommerell can cause symptoms of dysphagia - Aortic Arch Anomalies
- Aberrant left subclavian artery
- Mirror image branching
- Right aortic arch with left descending aorta
- Right aortic arch with aberrant branchiocephalic artery
- Right aortic arch with isolated left subclavian artery
- Double aortic arch
- Cervical aortic arch - Anomalies of the Aortic Arch: facts
- Frequency ranges from 0.5% to 3%
- Most patients asymptomatic though others may have dysphagia, dyspnea, hypertension or congestive heart failure
- Right aortic arch occurs in 0.1% of adults
- There are 6 paired arteries arising from the aortic sac during embryogenesis with the fourth left arch forming the aortic arch "A right aortic arch can occur in isolation or in association with congenital heart disease, especially in tetralogy of Fallot and truncus arteriosus. Edwards embryologic double aortic arch model can help explain the embryogenesis of many variations of right aortic arch." Right Aortic Arch and Its Variants
Kanne JP, Godwin D J
Cardiovascular Comput Tomogr (2010) 4,293-300 "Aneurysmal dilatation most often involves the right coronary Valsalva sinus, followed by the noncoronary and left coronary sinus. The clinical manifestations of ruptured and nonruptured Valsalva sinus aneurysms very widely, ranging from an asymptomatic heart murmor and insidiously progressive dyspnea to acute chest pain and cardiac arrest." Valsalva Sinus Aneurysms: Findings at CT and MR Imaging
Bricker AO et al.
RadioGraphics 2010; 30:99-110 - Valsalva Sinus Aneurysms: Complications
- Aortic regurgitation occurs in 30-50% of patients (both in ruptured and non-ruptured sinus aneurysms)
- Compression can comprimise coronary artery and lead to MI
- When they rupture they go most commonly into the right ventricle (55.6%) and right atrium (30.3%) - Valsalva Sinus Aneurysms: Facts
- Rare
- Can be either congenital or acquired
- Slightly more common in men
- Acquired causes; bacterial endocarditis, syphilis, TB, atherosclerosis, deceleration injury (rare)
- Congenital causes; Marfans, Ehlers-Danlos syndrome "Our study shows the feasibility of preoperative CT in aortic infective endocarditis for providing relevant data about the presence and relationships of aortic valvular pseudoaneurysms." Preoperative Evaluation in Aortic Endocarditis: Findings on Cardiac CT Gahide G et al.
AJR 2010; 194:574-578 - Why do we gate evaluation of the thoracic aorta?
- Quality evaluation of the entire thoracic aorta including the aortic sinus and aortic valve
- Definition of the coronary arteries especially in the proximal portions of the coronaary vessels "Optimal image quality for either technique is obtained with a relatively slow heart rate, which may require beta-blocker medication." Prospective and Retrospective ECG Gating for Thoracic CT Angiography: A Comparitive Study
Wu W et al.
AJR 2009;193:955-963 "Compared with retrospective ECG-gated thoracic CT angiography, prospective ECG-gated thoracic CT angiography was associated with a lower radiation dose, slightly increased contrast load, increased aortic attenuation values, and equivalent image quality." Prospective and Retrospective ECG Gating for Thoracic CT Angiography: A Comparitive Study
Wu W et al.
AJR 2009;193:955-963 - Takayasu Arteritis: Numano Classification
- Type IV: involvement of only the abdominal aorta with or without the renal arteries
- Type V: involvement of the entire aorta with branches
- Involvement of the coronary arteries or the pulmonary arteries is indicated with a C(+) or P(+) respectively - Takayasu Arteritis: Numano Classification
- Type I: involvement of only the branches of the aortic arch
- Type IIA: involvement of the ascending aorta or the aortic arch with or without branches
- Type IIB: involvement of the descending thoracic aorta with or without the ascending aorta or the aortic arch with its branches
- Type III: involvement of the entire descending aorta with or without the renal arteries - Takayasu Arteritis: Facts
- Large vessel arteritis that affects aorta and its branches
- Affects woman and young girls most commonly (80-90% are femal in second and third decade of life)
- Circumferential wall thickening is earliest finding
- Treatment includes steroids or immunosuppressive therapy as well as surgical revascularization of sites of involvement - Marfans Syndrome: Surgery
- Ascending aorta 45 mm or growing greater than 0.5 cm/yr is indication for surgery
- Repair is of root , aortic valve and ascending aorta - Marfans Syndrome: Cardiovascular Findings
- Minor Criteria - Dilatation or dissection of the descending or abdominal aorta before the age of 50 years
- Dilatation of the main pulmonary artery before age 40
- Mitral valve prolapse
- Calcification of the mitral valve before age 40
- Marfans Syndrome: Cardiovascular Findings
- Major Criteria - Dilatation of the ascending aorta involving at least the sinuses of Valsalva with or without aortic regurgitation
- Dissection of the ascending aorta
- Ghent Criteria: Major and Minor Findings
2 major and 1 minor criteria
or
1 major and 4 minor criteria - Marfan Syndrome: Facts
- Autosomal dominant
- Caused by mutations in the fibrillin-1 gene (FBN1) on chromosome 15
- Diagnosis based on Ghent criteria which include cardiovascular, ocular, and pulmonary abnormalities
- Average age of death in untreated patients is 35 years while in treated patients up to age 75 years - Supravalvular Aortic Stenosis: facts
- Focal or diffuse narrowing of the aorta starting at the sinotubular junction and often involves the entire ascending aorta
- SVAS may be associated with Williams-Beuren syndrome which is an autosomal dominant multisystematic disorder that may manifest with SVAS (71% of cases), mitral valve prolapse and pulmonary artery stenosis - Coarctation of the Aorta: Facts
- Male predominance (1.5:1)
- Aortic narrowing in region of ligamentum arteriosum just distal to the left subclavian artery
- Solitary lesion in 82% of cases but can be associated with Turner syndrome, bicuspid aortic valve, intracranial aneurysms, VSD and ASD defects, and Shone complex (left ventricular outflow tract obstruction and parachute mitral valve) - Patent Ductus Arteriosus: Facts
- PDA occurs in 1 of 2,000 children born full term
- More common in woman (2-1)
- Treatment includes surgical closure or percutaneous placement of an occluder device - Patent Ductus Arteriosus: Facts
- Connects the proximal descending aorta, immediately distal to the origin of the left subclavian artery, with the proximal left pulmonary artery at the junction of the main pulmonary artery
- Closes functionally 18-24 hours after birth and anatomically at one month
- If it is patent after 3 months it is a PDA "With its high spatial resolution and isotropic and volumetric information multidetector CT performed with or without ECG-gated technique allows accurate and fast noninvasive characterization of aortic pathologic conditions." Uncommon Congenital and Acquired Aortic Disease: Role of Multidetector CT Angiography
Kimura-Hayama ET, et al
RadioGraphics 2010; 30;79-98 "Multidetector CT is an alternative tool helpful in establishing the primary diagnosis, defining anatomic landmarks and their relationships, and identifying associated cardiovascular anomalies. It is also an adjunct in the evaluation of complications during follow-up." Uncommon Congenital and Acquired Aortic Disease: Role of Multidetector CT Angiography
Kimura-Hayama ET, et al
RadioGraphics 2010; 30;79-98
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