Diseases of the Great
Vessels
Susan A. Raaymakers, MPAS, PA-C, RDCS (AE)(PE)
Radiologic and Imaging Sciences - Echocardiography
Grand Valley State University, Grand Rapids, Michigan
raaymasu@gvsu.edu
Tyler Kahle Story
(20 minutes duration)

http://media.bestcare.org/TylerKahleStory
Normal Aortic Anatomy

Six Segments
1.
2.
3.
4.
5.
6.
Annulus
Sinuses of Valsalva
Sinotubular Junction
Ascending Tubular Aorta
Arch
Descending Thoracic
Aorta
Normal Aortic Anatomy

Six Segments

Annulus



Represents the junction of the
prox. Ao and the LVOT.
Part of fibrous skeleton of the
heart and is contiguous with the
anterior mitral valve leaflet and
perimembranous septum
Fibrinous structure so relatively
stable and resistant to
dilation:useful for indexing to
remaining aortic sizing
 NL 13 +/-1 mm/m2
 NL size 2.0-3.1cm
Normal Aortic Anatomy

Six Segments

Sinuses of Valsalva


Normal aorta dilates at
the level of the sinuses
by approximately 6
mm/m2
Three sinuses of Valsalva
of equivalent size
 Right and left contain
ostia of right and left
coronaries respectively
 Non
Normal Aortic Anatomy

Six Segments

Sinotubular Junction


Aorta tapers to within 2 to 3 mm
of annular size
Crucial to nature of aortic valve
coaptation
 Insertion of aortic valve cusps:
continuous from the level of the
annuls up through the sinuses
to the level of the sinotubular
junction
 Dilatation of sinotubular junction
may result in splaying of
coaptation line of the aortic
cusps leading to secondary
aortic insufficiency
Normal Aortic Anatomy

Six Segments

Ascending Tubular Aorta


Dimension similar to sinotubular
junction
Ascending aorta terminates at the
left innominate artery
(brachiocephalic) where aortic
arch begins and continuous to the
left subclavian and ligamentum
arteriosum
Normal Aortic Anatomy

Six Segments

Arch

Three major branch vessels
 Innominate artery (brachiocephalic), left common carotid and left
subclavian

Descending Thoracic Aorta
Walls of the Aorta

Intima


Media


Thin and smooth
Elastic and muscular
Adventitia

Outer layer
Echocardiographic Evaluation
Echocardiographic Evaluation

Evaluation of the intrathoracic portion of
the aorta and of aortic disease


TTE: limited to proximal ascending aorta and a
small portion of the descending aorta behind
LA
Major use of TEE: high-resolution view of
entire length of aorta form aortic valve to
approximately the diaphragm

Accuracy equivalent to computed tomography (CT)
and magnetic resonance imaging (MRI)
Echocardiographic Evaluation

Superior angulation in parasternal longaxis view

Emphasizes visualization of normal ascending
aorta (typically 4 -5 cm may be seen)
20.03 Feigenbaum
Echocardiographic Evaluation

Suprasternal notch view


Images more feasible in children and
adolescents
Occasional discomfort of ultrasound probe in
this area
20.4 Feigenbaum
Echocardiographic Evaluation

Descending thoracic aorta seen in


Parasternal long axis behind LA
Level of the gastroesophageal junction,
posterior apical four chamber view
Non-dynamic
Echocardiographic Evaluation
Echocardiographic Evaluation

Transesophageal

Broader window than transthoracic

Visualization from annulus through ascending and
arch to level of gastroesophageal
Non-dynamic
Echocardiographic Evaluation

Transesophageal

Typically imaging begins with
imaging of the ascending aorta
with probe behind the left
atrium

Proximal 5 to 10 cm of the
ascending aorta can be
visualized

Scanning at a 120-degree
imaging plane
Non-dynamic
Echocardiographic Evaluation

Transesophageal


Rotate probe 30-60°
Series of short-axis views of
proximal ascending aorta
including short axis of aortic
valve
Non-dynamic
Echocardiographic Evaluation

Transesophageal


Descending aorta
Insertion of TEE probe deeper
toward gastroesophageal
junction
Non-dynamic
Intravascular Ultrasound

Performed with high-frequency: 20-30
MHz


Used in diagnosis and management of aortic
dissection and as a primary imaging tool
Allows highly detailed, high-resolution
Plaque
Aortic rupture
Diseases of the Aorta
Aortic Dilatation
 Aortic Dissection
 Thoracic Aortic Aneurysms
 Traumatic Injury
 Aortic Atherosclerosis
 Sinus of Valsalva Aneurysms

Aortic Dilatation

Dilatation can occur at any point along
aorta



Primary
Secondary
Idiopathic dilatation


Also referred to as Anuloaortic ectasia
Unclear whether distinct disease entity due
to aging, hypertension or unrecognized
disease of aorta
Aortic Aneurysm


Definition: Localized abnormal dilatation of aorta
containing all three layers of the aortic wall
Pathophysiology: Weakened media of the aorta
Tunica intima
Tunica media
Tunica externa
Aortic Aneurysm
Types


Saccular
Fusiform
Locations
Ascending aorta
 Aortic Arch
 Descending Thoracic Aorta
 Abdominal Aorta

45%
10%
35%
10%
Causes for Aortic Aneurysms
Atherosclerosis
 Medial Degeneration





Idiopathic (annuloaortic ectasia)
Marfan's Syndrome
Other heritable disorders
Associated with Bicuspid Aortic Valve
More Causes
Aortic Dissection with Dilitation of
persisting false lumen
 Trauma with incomplete aortic rupture
 Syphilis
 Mycotic (Bacterial, Fungal, Tuberculous
aortitis)
 Noninfectious aortitis (Giant-cell,
Takayasu’s Syndrome)

Aortic Dilatation

Primary

Occurs with cystic medial necrosis

Typified by Marfan’s
 May be seen in other connective ts disorders

Results in weakening of medial layers
 Subsequent dilation and aneurysm formation
Aortic Dilatation

Marfan’s


Primary
Characteristically involves ascending aorta and sinuses
Imaging recommendations:
 Radiography for skeletal abnormalities
 Serial chest radiography for demonstration of progressive
aortic dilation
 2D echocardiography for early dx and monitoring of aortic
dilation
 CT or MRI for evaluation of aortic disease
Aortic Dilatation

Secondary
Volume or pressure overload states


AI or HTN
Post stenotic aortic dilation

Valvular aortic stenosis
20.11 Feigenbaum
Aortic Dilatation

Dilated ascending aorta

Effacement (loss of tapering) of the sinotubular
junction

Classic effacement
 Sinotubular junction: same dimension as Valsalva sinus
Non-dynamic
Aortic ANEURYSMS

May occur in ascending aorta

Typically past sinotubular junction

Better visualized with TEE
20.11 Feigenbaum
Aortic ANEURYSMS
20.13 Feigenbaum
Aortic ANEURYSMS and DILATION

Rupture or dissection


Directly related to degree of dilation
Indication for prophylactic aortic surgery

55 mm
 Many centers use 50 mm

Rapid change in dilation (<than 5 mm per year)
Non-dynamic images
Marfan’s Syndrome


Inherited connective tissue disorder
Echocardiography: initial screening tool for
patients or first-degree relatives




TEE for more specific information
Marked dilation of ascending aorta
Disproportionate involvement of sinuses of
Valsalva
Early cases


Mild dilation of sinus
Sinotubular effacement

Malcoaptation of aortic cusps
 Resultant in AI
Marfan’s Syndrome
Patient #1
20.20b Feigenbaum
Patient #2
Level of sinuses: 5.8 cm
Aortic annulus: 2.8 cm
20.21a Feigenbaum
Valsalva Sinus Aneurysm
 May
form from any of the three
Valsalva sinuses

Most often arise form the right sinus
 Size:
highly variable
 Aneurysms arising from the right
Valsalva sinus typically protrude
down into the right atrium

Appear as “windsock” structure in the
right atrium
Valsalva Sinus Aneurysm

Right sinus of Valsalva aneurysm

Protruding into right ventricular outflow tract
20.24a Feigenbaum
20.24b Feigenbaum
Valsalva Sinus Aneurysm

Right sinus of Valsalva aneurysm

Protruding into right ventricular outflow tract
20.24a-c Feigenbaum
Valsalva Sinus Aneurysm

Colorflow

Major complication of Valsalva Sinus Aneurysm: rupture

Most common location for rupture: right atrium
 Results in instantaneous elevation of right heart pressures
 Jugular distension
 Loud continuous murmur
20.26 Feigenbaum
20.27 Feigenbaum
Valsalva Sinus Aneurysm

Colorflow

Major complication of Valsalva Sinus Aneurysm: rupture

Most common location for rupture: right atrium
 Results in:
 Instantaneous elevation of right heart pressures
Aortic Dissection
Acute

Symptoms



Typically occurs with pre-existing




Sudden onset of severe chest pain and/or back
pain
Wide range of secondary cardiovascular and
physiologic abnormalities
Aortic dilation
Cystic medial fibrosis due to Marfan’s
syndrome
Long standing hypertension
Any aspect of the aorta may dissect
Aortic Dissection

Two Basic Variants


Classic
Spontaneous hematoma
Aortic Dissection

Classic



Tear from lumen through the intima into the medial
layer with subsequent propagation of a column of blood
Further dissect the intima away form the media
Propagation may be both proximal and distal to the
initial intimal tear
Aortic Dissection

Classic

Typically begins either

At the area of the ligamentum arteriosum
 Propagates through the arch and into the ascending
aorta

Or starts in ascending aorta and propagate distally
Aortic Dissection

Spontaneous Intramural Hematoma


Clinical presentation with respect to nature of
symptoms: virtually identical to classic
dissection
Hemorrhage into the medial layer then
dissects proximally or distally to a variable
degree WITHOUT rupture into the adventitia
Aortic Dissection

Two schemes for identification



Stanford (A-B)
DeBakey (1, 2, 3)
Types

Type A(1): (70% occurrence)
Throughout ascending and
descending aorta

Type A(2): (5% occurrence)
Confined to ascending aorta

Type B(3): (25% occurrence)
Confined to descending aorta

Isolated: Aortic arch
Type II Dissection
20.31 Feigenbaum
20.35 Feigenbaum
20.34 Feigenbaum
Type II Dissection
20.31 Feigenbaum
20.35 Feigenbaum
20.34 Feigenbaum
True and False Lumens

True lumen





Pulsatile aortic flow
Expand w/systole
Circular or ovale typically
In descending aorta: usually
smaller of the two lumens
False lumen



Continuous flow in venous flow
pattern
Often filled with twirling
homogenous echoes (stasis of
blood or frank thrombus)
Tags of tissue (small muscle
remnants where the intima has
been sheared from the media)
Non-dynamic
True and False Lumens
True lumen
False lumen
20.36a Feigenbaum
20.36a Feigenbaum
Type III Aortic Dissection

Descending aortic dissection
20.39b Feigenbaum
Imaging Goals for Dissection

Ascending dissection
 Most are detected by TEE rather than
TTE
20.30b Feigenbaum
20.30a Feigenbaum
Intramural Hematoma



May occur at any point along the aorta
More common in the descending aorta and arch
Appears as a smooth homogenous concentric
thickening of the wall


Typically > 7 mm in thickness
No active flow with the “lumen” and no tear in
the intima
20.44 Feigenbaum
Goals of Imaging









Confirmation of diagnosis
Location
Extent of dissection
Mechanism of AI
Presence of pericardial or pleural effusions
Coronary artery involvement
Head vessel involvement
Detection of rupture
Location of:


Intimal tear (entry)
Re-entry site
Transesophogeal Echo
Superior over transthoracic echo
 CT, MRI and Aortography are also
common methods of diagnosis
 Pitt falls of TEE




Reverberations, catheters
Mirror image artifacts
Thoracic aneurysm with mural thrombus
Echo Findings

2D




MM



Presence of an intimal flap, which may appear as a thin
linear structure
A true and a false lumen
Pericardial effusion
Dilated aorta >4.2cm
Increased aortic wall thickness
Color/Doppler


AI
Flow between the true and false lumen
Role of TEE
Best for seeing ascending aortic
aneurysms
 Helps rule out aortic dissection versus
aortic aneurysm
 Instant results

Non-dynamic
Mechanisms of AI
Dilatation of aortic root
 Asymmetric dissection causes faulty
coaptation of the aortic valve
 Prolapsing intimal flap back through the
aorta

Aortic Atheroma

Atherosclerosis of the aorta






Frequently encountered in TEE
May be identified in SSN view
Common in advanced age, HTN, elevated
cholesterol
May be a component of atherosclerotic
aneurysm and intramural hematoma of the
aorta
Most common in descending aorta
Less frequently in ascending aorta
Aortic Atheroma

Characterized as symmetric and crescentic
(curved shaped)

Smooth, homogenous crescent filling a portion
of the aortic lumen, protruding or complex


Complex: defined as atherosclerotic disease with
epedunculated or mobile components
Grading System



I = 1 – 3.9mm thickness
II = > 4mm thickness
III = Debris (mobile regardless of size)
Aortic Atheroma
Two Different Patients
20.50a Feigenbaum
20.50b Feigenbaum
Miscellaneous Conditions
Aortic Pseudoaneurysm



Contained rupture of the aorta
Characterized by an extraluminal aneurysmal sack communicating
with the true lumen by a relatively narrow neck
Occur in several situations



Spontaneous rupture of an aortic aneurysm with subsequent sealing
off of the hemorrhage
Sequelae of aortic dissection with further rupture through the
adventitial layers
Rare occasions: iatrogenic injury
20.55 Feigenbaum
Miscellaneous Conditions
Aortic Trauma

Wide spread of extent of injury/pathology






Simple contusion
Intimal tear
Intramural hematoma
False Aneurysm
Frank rupture (transection)
Major dissection NOT a feature of aortic trauma(usually
no underlying medial disease)
Miscellaneous Conditions
Aortic Trauma

Blunt chest injury


High-speed impact injury (i.e. unrestrained MVA)
Partial or complete transection of the descending aorta,
classically at area of ligamentum arteriosum



Complete = nearly instantaneous fatal event
Partial = hemorrhage and shock
CT or MRI typically primary diagnostic tool
Traumatic Injury Cont.

Intimal Lacerations (transection)

The mechanism of injury historically
was thought to be rapid deceleration
with "whipping" of the aorta at points
of attachment (i.e., aortic root,
ligamentum arteriosus, diaphragmatic
hiatus).

More recent evidence suggests that
injury at the most common site, the
aortic isthmus, is due to

Compression of the anterior chest wall
and pinching of the aorta between
structures of the anterior bony thorax
and the thoracic spine.
Aortic Infections – mentioned earlier
under causes of aortic aneurysm
Bacterial or fungal infections of the aorta
is rare
 Manifest as a pedunculated mobile mass
 Syphilic aortic disease: rare encountered
in contemporary practice


Results in inflammatory thickening of the
proximal aorta
Aortic Thrombus




Rare
Bland mobile thrombus form within the thoracic aorta
More common in the proximal descending thoracic aorta
and is often associated with evidence of peripheral
embolization
Thrombi are highly mobile echo-dense masses within the
lumen, appear attached to the aortic wall by a fairly thin
stalk
20.59 Feigenbaum
Takayasu Arteritis




Inflammatory disease of the aorta and its proximal branches
Occurs in patients <40 years old
Results in marked, irregular intimal thickening and accumulation
of inflammatory tissue in the proximal aorta and ostia of major
branches including the coronary arteries
Echo: appears similar to atheroclerotic disease
20.61 Feigenbaum
Pulmonary Artery
Abnormalities
Pulmonary Artery Abnormalities

Most abnormalities of PA: congenital




Postenotic dilation
Branch pulmonary artery stenosis
Abnormal position of the pulmonary artery
Transposition of the great vessels

May also be involved by systemic diseases such
as Takayasu arteritis

Pulmonary artery dissection: rare

Reported in patients with chronic pulmonary
hypertension
Pulmonary Artery Abnormalities

Dilated pulmonary arteries




Right-sided volume overload (e.g., atrial septal
defect)
Pulmonary hypertension
Idiopathic dilation of the pulmonary artery
(Rare)
Finding of dilated PA mandates careful
evaluation for:

Right-sided pressure or volume overload
Pulmonary Artery Abnormalities

Standard views





PSAX
RVOT
Subcostal four with severe anterior tilt
SSN (right pulmonary artery)
High parasternal short axis
RPA
LPA
Non-dynamic
Pulmonary Artery Abnormalities

Transesphageal


0° esophageal level superior the LA
Long axis of pulmonary artery

May not be obtained in all patients d/t interposition of
the air-filled bronchus
RPA
LPA
SVC
AO
MPA
12-005 Feigenbaum
Pulmonary Artery Abnormalities

Transesphageal



90° plane (analogous to TTE RVOT view)
Image quality may be suboptimal due to
distance of PA from transducer in this view
Alternative studies




CT
MRI
Contrast angiography
Radionuclide ventilation/perfusion scan for
evaluation for pulmonary embolism
Pulmonary Artery Abnormalities

Limitations and alternative approaches

Acoustic access and quality


Body habitus and skill of sonographer
Interpretation must consider the likelihood of
 False-positive findings from beam-width artifacts,
reverberations and oblique image planes
 False-negative findings due to limited acoustic access and
poor resolution

Chest CT



Advantages: wide field of view, high accuracy and wide
availability
Disadvantages: ionizing radiation and non-portable nature
of the study
MRI

Advantages: high resolution, high diagnostic accuracy,
wide field of view and ability to orient the images along the
long axis of the aorta
Sources

Feigenbaum H, Armstrong W. (2004). Echocardiography. (6th
Edition). Indianapolis. Lippincott Williams & Wilkins.

Goldstein S., Harry M., Carney D., Dempsey A., Ehler D., Geiser
E., Gillam L., Kraft C., Rigling R., McCallister B., Sisk E.,
Waggoner A., Witt S., Gresser C.. (2005). Outline of Sonographer
Core Curriculum in Echocardiography.

Otto C. (2004). Textbook of Clinical Echocardiography. (3rd
Edition). Elsevier & Saunders.

Reynolds T. (2000). The Echocardiographer's Pocket Reference.
(2nd Edition). Arizona. Arizona Heart Institute.