Figure 1
CTA
CTA maximum intensity projection coronal reconstruction depicting the Stanford type B aortic dissection.
A rare association: Type B aortic dissection in a patient with aortic coarctation
SectionCardiovascular
Case TypeClinical Cases
AuthorsMadalena Ramalho, Tiago Rodrigues, António Costa, José Fonseca Santos
Connected authors
62 years, male
Clinical History
A 62-year-old male patient was referred to our institution with the diagnosis of type B aortic dissection (AD).
The patient had a medical history of arterial hypertension, ischaemic cardiopathy and chronic obstructive pulmonary disease. There was no known hereditary diseases or previous invasive aortic procedures.
The patient had a medical history of arterial hypertension, ischaemic cardiopathy and chronic obstructive pulmonary disease. There was no known hereditary diseases or previous invasive aortic procedures.
Imaging Findings
In order to further evaluate the case and consider the adequate therapeutic approach we performed a Computed Tomography Angiography (CTA).
The CTA showed a marked focal narrowing in the initial segment of the thoracic descending aorta, features of a post-ductal aortic coarctation (AC).
A Stanford type B aortic dissection (AD) was also detected just distal to the coarctation site extending to the left common iliac artery. Parietal thrombosis could be seen along the false lumen.
As a result of the chronic narrowing of the aortic lumen there were multiple collateral vessels to allow the flow of blood to the post-coarction part of the descending aorta, which included internal thoracic, intercostal and vertebral arteries.
The CTA showed a marked focal narrowing in the initial segment of the thoracic descending aorta, features of a post-ductal aortic coarctation (AC).
A Stanford type B aortic dissection (AD) was also detected just distal to the coarctation site extending to the left common iliac artery. Parietal thrombosis could be seen along the false lumen.
As a result of the chronic narrowing of the aortic lumen there were multiple collateral vessels to allow the flow of blood to the post-coarction part of the descending aorta, which included internal thoracic, intercostal and vertebral arteries.
Discussion
AC consists in a segmental narrowing of the distal arch or descending aorta. [1] There are two AC types: the pre-ductal type, an uncommon form seen in neonates, with aortic stenosis located above the left subclavian artery and associated with an hypoplastic arch; the post-ductal type (more frequent) is characterised by abrupt stenosis of a focal segment of the descending aorta, distal to the left subclavian artery. [1]
AD results from the separation of the aortic wall layers, when a tear in the intima allows the blood to enter the intima-media space, creating a blood-filled false lumen. [2] Stanford classification systems divide dissections according to the involvement of the ascending aorta: type A involves the ascending aorta and type B starts distal to the brachiocephalic vessels. [3]
AC is a known risk factor to type A aortic dissection, as it causes upper body hypertension and ascending aorta dilatation. [4] However, the association between type B aortic dissection with AC is rare, because blood pressure and arterial wall tension is reduced distal to the coarctation. [4, 5] The majority of these cases have iatrogenic aetiology (after surgical or endovascular aortic procedures), with only a few reported cases of spontaneous dissection (most of them associated with connective tissue abnormalities of the aortic wall and poststenotic dilatation of the descending aorta). [4]
Although conventional angiography and magnetic resonance are capable of detecting and delineating AC and AD, nowadays, CTA has become the first-line imaging technique in the evaluation of these pathologies, because of its availability, speed, and multiplanar reformatting capabilities.
The classic features of AD are an intimal flap and false lumen. [2] Unenhanced scans can show high-attenuation of an acutely thrombosed false lumen, internal displacement of intimal calcification and mediastinal or pericardial haematoma. Delayed enhancement of the false lumen, mural thickening with increased attenuation, and irregular compression of the true lumen by an expanding intramural haematoma or thrombus are features that can also be seen in aortic dissection. If aortic branch vessels are supplied from the false lumen, organ ischaemia or infarction can occur. [2]
In AC, CTA with multiplanar reformations allows an easy detection of the focal narrowing of the aorta and characterisation of the type of coarctation, degree of narrowing and the presence of any arterial thrombus. [1, 5] Other important findings are the presence of collateral arteries. [1]
The treatment of the few cases described in the literature is surgical. [4, 5] CTA allows prompt diagnosis and characterisation of the aorta, permitting optimal therapeutic management.
AD results from the separation of the aortic wall layers, when a tear in the intima allows the blood to enter the intima-media space, creating a blood-filled false lumen. [2] Stanford classification systems divide dissections according to the involvement of the ascending aorta: type A involves the ascending aorta and type B starts distal to the brachiocephalic vessels. [3]
AC is a known risk factor to type A aortic dissection, as it causes upper body hypertension and ascending aorta dilatation. [4] However, the association between type B aortic dissection with AC is rare, because blood pressure and arterial wall tension is reduced distal to the coarctation. [4, 5] The majority of these cases have iatrogenic aetiology (after surgical or endovascular aortic procedures), with only a few reported cases of spontaneous dissection (most of them associated with connective tissue abnormalities of the aortic wall and poststenotic dilatation of the descending aorta). [4]
Although conventional angiography and magnetic resonance are capable of detecting and delineating AC and AD, nowadays, CTA has become the first-line imaging technique in the evaluation of these pathologies, because of its availability, speed, and multiplanar reformatting capabilities.
The classic features of AD are an intimal flap and false lumen. [2] Unenhanced scans can show high-attenuation of an acutely thrombosed false lumen, internal displacement of intimal calcification and mediastinal or pericardial haematoma. Delayed enhancement of the false lumen, mural thickening with increased attenuation, and irregular compression of the true lumen by an expanding intramural haematoma or thrombus are features that can also be seen in aortic dissection. If aortic branch vessels are supplied from the false lumen, organ ischaemia or infarction can occur. [2]
In AC, CTA with multiplanar reformations allows an easy detection of the focal narrowing of the aorta and characterisation of the type of coarctation, degree of narrowing and the presence of any arterial thrombus. [1, 5] Other important findings are the presence of collateral arteries. [1]
The treatment of the few cases described in the literature is surgical. [4, 5] CTA allows prompt diagnosis and characterisation of the aorta, permitting optimal therapeutic management.
Differential Diagnosis List
Type B aortic dissection with aortic coarctation
Intramural haematoma
Penetrating atherosclerotic ulcer
Pseudo-coarctation
Final Diagnosis
Type B aortic dissection with aortic coarctation
References
[1] Karaosmanoglu AD, Khawaja RD, Onur MR, Kalra MK. (2015) CT and MRI of Aortic Coarctation: Pre- and Postsurgical Findings. Am J Roentgenol Mar;204(3):W224-33 (PMID: 25714305)
[2] McMahon MA, Squirrell CA. (2010) Multidetector CT of Aortic Dissection: A Pictorial Review. Radiographics Mar;30(2):445-60 (PMID: 20228328)
[3] Macura KJ, Corl FM, Fishman EK, Bluemke DA. (2003) Pathogenesis in acute aortic syndromes: aortic dissection, intramural hematoma, and penetrating atherosclerotic aortic ulcer. Am J Roentgenol Aug;181(2):309-16 (PMID: 12876003)
[4] Yanase Y, Kawaharada N, Hagiwara T, Nakazawa J, Maeda T, Koyanagi T, Ito T, Kurimoto Y, Higami T. (2011) Surgical treatment for aortic coarctation with chronic type B dissection: report of a case. Ann Vasc Dis 4(4):353-5 (PMID: 23555479)
[5] Shin JS, Sun K, Shim WJ, Kim KT, Kim HM. (2002) Acute descending aortic dissection associated with coarctation in adult. Asian Cardiovasc Thorac Ann 10(4):354-5 (PMID: 12538288)
Case information
| URL: | https://eurorad.org/case/14796 |
| DOI: | 10.1594/EURORAD/CASE.14796 |
| ISSN: | 1563-4086 |
License
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Figure 2
CTA
CTA maximum intensity projection sagittal reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin. A Stanford type B aortic dissection is seen distal to the coarctation.
CTA maximum intensity projection sagittal reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin (circle). A Stanford type B aortic dissection is seen distal to the coarctation.
CTA tridimensional reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin. A Stanford type B aortic dissection is seen distal to the coarctation.
CTA tridimensional reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin (circle). A Stanford type B aortic dissection is seen distal to the coarctation.
Figure 3
CTA
CTA maximum intensity projection axial reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin. A Stanford type B aortic dissection is seen distal to the coarctation.
CTA maximum intensity projection axial reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin (circle). A Stanford type B aortic dissection is seen distal to the coarctation.
Figure 4
CTA
CTA maximum intensity projection axial reconstruction illustrating an extensive network of collateral vessels allowing the flow of blood from high to low pressure zones via spinal and intercostal arteries.
CTA maximum intensity projection axial reconstruction illustrating an extensive network of collateral vessels allowing the flow of blood from high to low pressure zones via spinal and intercostal arteries (circles).
CTA maximum intensity projection axial reconstruction illustrating an extensive network of collateral vessels allowing the flow of blood from high to low pressure zones via internal thoracic and intercostal arteries.
CTA maximum intensity projection axial reconstruction illustrating an extensive network of collateral vessels allowing the flow of blood from high to low pressure zones via internal thoracic and intercostal arteries (circles).
CTA
CTA maximum intensity projection coronal reconstruction depicting the Stanford type B aortic dissection.
Hospital de Santa Maria
Hospital de Santa Maria
CTA
CTA maximum intensity projection sagittal reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin. A Stanford type B aortic dissection is seen distal to the coarctation.
Hospital de Santa Maria
Hospital de Santa Maria
CTA maximum intensity projection sagittal reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin (circle). A Stanford type B aortic dissection is seen distal to the coarctation.
Hospital de Santa Maria
Hospital de Santa Maria
CTA tridimensional reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin. A Stanford type B aortic dissection is seen distal to the coarctation.
Hospital de Santa Maria
Hospital de Santa Maria
CTA tridimensional reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin (circle). A Stanford type B aortic dissection is seen distal to the coarctation.
Hospital de Santa Maria
Hospital de Santa Maria
CTA
CTA maximum intensity projection axial reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin. A Stanford type B aortic dissection is seen distal to the coarctation.
Hospital de Santa Maria
Hospital de Santa Maria
CTA maximum intensity projection axial reconstruction showing a marked focal narrowing of the thoracic aorta immediately after left subclavian artery origin (circle). A Stanford type B aortic dissection is seen distal to the coarctation.
Hospital de Santa Maria
Hospital de Santa Maria
CTA
CTA maximum intensity projection axial reconstruction illustrating an extensive network of collateral vessels allowing the flow of blood from high to low pressure zones via spinal and intercostal arteries.
Hospital de Santa Maria
Hospital de Santa Maria
CTA maximum intensity projection axial reconstruction illustrating an extensive network of collateral vessels allowing the flow of blood from high to low pressure zones via spinal and intercostal arteries (circles).
Hospital de Santa Maria
Hospital de Santa Maria
CTA maximum intensity projection axial reconstruction illustrating an extensive network of collateral vessels allowing the flow of blood from high to low pressure zones via internal thoracic and intercostal arteries.
Hospital de Santa Maria
Hospital de Santa Maria
CTA maximum intensity projection axial reconstruction illustrating an extensive network of collateral vessels allowing the flow of blood from high to low pressure zones via internal thoracic and intercostal arteries (circles).
Hospital de Santa Maria
Hospital de Santa Maria