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CHAPTER 23
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Arterial Disease
1. Which of the following is TRUE about computed tomography angiography (CTA) in evaluation of arterial
disease?
A. CTA is more accurate than angiography and evalua-
tion of lower extremity arterial occlusive disease.
B. Blooming artifact is the term used to describe artifact
secondary to thrombus formation in the aorta and
arteries.
C. As a low dose of contrast is used, it is unlikely to be
associated with kidney complications.
D. CTA has sensitivity, specificity, and accuracy that is
equivalent to invasive angiography.
2. Vascular stents can be used in the vascular system for
inadequate angioplasty with dissection or elastic recoil
of an arterial stenosis. Which of the following statements
appropriately describes vascular stents?
A. All vascular stents are made of metals that contain
stainless steel that will help self-expanding.
B. Vascular stents should be oversized by 1 to 2 mm
relative to the largest diameter of the normal vessel
adjacent to the lesion in order to prevent immediate
migration.
C. Vascular stents are used in short stenotic segments
because of their ability to expand and accommodate the area of stenosis without shortening or
lengthening.
D. Balloon expandable stents have a longer time to com-
plete endothelialization.
Answer: D
CTA is a noninvasive contrast-dependent method of imaging
arterial system. The contrast-filled vessels can be extracted
from the slices and rendered in the three-dimensional format.
CTA is increasingly being used to image the carotid bifurcation, and as computing power increases, the speed of image
acquisition and the resolution will continue to increase. The
major limitations of multidetector CTA are use of contrast
and presence of artifacts caused by calcification and stents.
CTA can overestimate the degree of in-stent stenosis, while
heavy calcification can limit the diagnostic accuracy of the
method by causing a “blooming artifact.” The artifact can
be overcome with alteration in image acquisition technique.
There are no randomized trials to document the superiority of multidetector CTA of compared to traditional angiography, but there is emerging evidence to support the claim
that multidetector CTA has sensitivity, specificity, and accuracy that rival invasive angiography. (See Schwartz 11th ed.,
pp. 901–902.)
Answer: B
Vascular stents are commonly used after inadequate angioplasty with dissection or elastic recall of arterial stenosis.
Appropriate indications for primary stenting of the lesion
without an initial trial of angioplasty alone are evolving and
managed that are dependent on the extent and the site of
the lesion. Stents are manufactured from a variety of metals including stainless steel, tantalum, cobalt basaloid, and
Nitinol. Vascular stents are classified into two basic categories: balloon-expandable stents and self-expanding stents.
These stents are always oversized by 1 to 2 mm relative to
the largest diameter of normal vessel adjacent to the lesion in
order to prevent immediate migration. With the involvement
of the cisterns, there is some degree of shortening that has
to be taken into account when choosing the area of deployment. Self-expanding stents can continually expand after
delivery; this allows them to accommodate adjacent vessels
of different size. Balloon-expandable stents are usually composed of stainless steel, mounted on an angioplasty balloon,
and deployed by a balloon inflation. Shortening of balloonexpandable stent during deployment depends on both the
stent geometry and the final diameter to which the balloon
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is expanded. The cisterns are more rigid and are associated
with a shorter time to complete endothelialization. They are
often of limited flexibility and have a higher degree of crush
resistance when compared to the self-expanding stents. (See
Schwartz 11th ed., pp. 905–906.)
3. An evaluation of the arterial segments of the lower
extremities, pulse volume recording (PVR) has which of
CHAPTER 23
Arterial Disease
the following characteristics?
A. The cuff is inflated to above systolic pressure to detect
pulse volume changes.
B. Brisk upstroke of the waveform in the pulse volume
recording is suggestive of proximal disease.
C. When compared with angiography, PVR has an accu-
racy of 30%.
D. Its best application is in patients with noncompress-
ible vessels that would interfere with accurate measurement of segmental pressures.
4. Which of the following is TRUE about patients with a
stroke?
A. Eighty-five percent of all strokes are hemorrhagic
and 15% are ischemic.
B. The commonest cause of the stroke is lacunar stroke.
It occurs in about 30% of the patients.
C. Cerebrovascular accident is used interchangeably
with hemorrhagic stroke.
D. Prior history of neurological symptoms such as tran-
sient ischemic attack (TIA) or stroke is a predictor for
recurrent ipsilateral stroke.
Answer: D
PVR is used specifically in patients with noncompressible
vessels where segmental plethysmography can be used to
determine the underlying arterial occlusive disease. Pressure
measurement in such patients is not accurate because of noncompressibility. Capsule placed at different levels on the leg
detect changes in blood volume and he produced a graft. To
obtain accurate PVR waveforms, the cuff is inflated to a pressure of 60 to 65 mm Hg, so as to detect volume changes without
causing arterial occlusion. Pulse volume tracings are suggestive
of proximal disease of the upstroke of the pulse is not brisk,
the peak of the wave tracing is rounded, and there is disappearance of the dicrotic notch. Although isolated segmental
limb pressures and PVR measurements are 85% accurate when
compared with angiography in detecting and localizing significant atherosclerotic lesions, when using combination, accuracy
reaches 95%. (See Schwartz 11th ed., p. 900.)
Answer: D
Approximately 700,000 Americans suffer an annual or recurrent stroke each year. Eighty-five percent of all strokes are ischemic and 15% are hemorrhagic. Common causes of ischemic
stroke are cardiogenic emboli in 35%, carotid artery stenosis
in 30%, lacunar in 10%, miscellaneous in 10%, and idiopathic
in 15%. The term “cerebrovascular accident” is often used
interchangeably to refer to an ischemic stroke. The severity
of carotid artery stenosis is a strong predictor for stroke with
more severe occlusive disease is associated with a higher incidence of stroke. A prior history of neurologic symptoms such
as TIA or stroke is an important determinant for recurrent
ipsilateral stroke. (See Schwartz 11th ed., p. 907.)
5. The following conditions qualify patients for being high
surgical risk for carotid endarterectomy EXCEPT:
A. High carotid bifurcation above C2 vertebral body.
B. Low common carotid artery, below clavicle.
C. Ipsilateral laryngeal nerve palsy.
D. Tracheostomy.
Answer: C
Since carotid artery stenting was approved by the US Food
and Drug Administration (FDA) for the clinical application
in 2004, the procedure has become a treatment alternative
in patients who are considered high risk for endarterectomy. Conditions that qualify patients as high surgical risk
for carotid endarterectomy include anatomical factors: High
carotid bifurcation above C2 vertebral body, low common
carotid artery below clavicle, contralateral carotid occlusion,
restenosis of ipsilateral prior carotid endarterectomy, previous neck irradiation, prior radical neck dissection, contralateral laryngeal nerve palsy, and presence of tracheostomy.
In addition, physiological factors that are considered as
high surgical risk for carotid endarterectomy include: Age
≥ 80 years, left ventricular ejection fraction (<30%), New York
Heart Association class III/IV congestive heart failure, unstable angina (Canadian Cardiovascular Society class III/IV
angina pectoris), recent myocardial infarction, clinically significant cardiac disease (congestive heart failure, abnormal
stress test, or need for coronary revascularization), severe
chronic obstructive pulmonary disease and end-stage renal
disease on dialysis. (See Schwartz 11th ed., pp. 911–912.)
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6. In regard to cerebral monitoring during carotid endarterectomy, which of the following is TRUE?
A. If the patient is awake, the best monitoring is stump
pressure.
B. Electroencephalogram (EEG) reflecting focal
decreases in amplitude and slowing of the EEG waves
are reflective of cerebral ischemia.
C. A decrease to <80% of baseline velocity in the ipsi-
lateral middle cerebral artery is a sign of cerebral
ischemia.
D. Stump pressure measurement is the most sensitive
test for potential cerebral ischemia.
Answer: B
Of both, carotid endarterectomy is one of the earliest vascular
operations ever described. This technique has been perfected
in the last two decades, surgeons continue to debate many
aspects of this procedure. For instance, there is no universal
agreement with regard to the best anesthetic of choice, the
best intraoperative cerebral monitoring, whether to routinely
shunt, open versus eversion endarterectomy, and patch versus
primary closure. Depending on the anesthetic given, the surgeon must decide whether intraoperative cerebral monitoring
is necessary or intra-arterial carotid shunting would be used.
In general, if the patient is awake, then his or her abilities to
respond to commands during carotid clamp determine the
adequacy of cerebral perfusion to the ipsilateral hemisphere.
On the other hand, intraoperative EEG or transcranial power
Doppler (TCD) has been used to monitor for adequate cerebral perfusion during the clamp. For patients undergoing
surgery under general anesthesia, focal ipsilateral decreases
in amplitude and slowing of EEG waves are indicative of cerebral ischemia. Similarly, a decrease to <50% of baseline velocity in the ipsilateral middle cerebral artery is a sign of cerebral
ischemia. For patients with poor collateral flow exhibiting
signs of cerebral ischemia, intra-arterial carotid shunting
with removal of the clamp will restore cerebral flow for the
remaining part of the surgery. Stump pressures have been
used to determine the need for intra-arterial carotid shunting. Some surgeons prefer to shunt all patients on a routine
basis and not use intraoperative cerebral monitoring. (See
Schwartz 11th ed., pp. 912–913.)
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Arterial Disease
7. Regarding carotid body tumors, which of the following is
TRUE?
A. The normal carotid body is located in the media or
the transition. Between the media and intima at the
bifurcation of the common carotid artery.
B. Carotid body tumors are rare lesions of neuromuscu-
lar system.
C. Approximately 20% to 25% of carotid body tumors
are malignant.
D. About 35% of the carotid body tumors are hereditary.
8. Which of the following is TRUE in relation to abdominal
aortic aneurysm?
A. Sixty percent of an AAA are infrarenal in location.
B. There is a higher predilection for juxtarenal and
suprarenal AAAs in women compared with men.
C. Clinically significant peripheral occlusive disease is
common with AAA and is present in about 40% of all
cases.
D. Concomitant common iliac and/or hypogastric
artery aneurysms of care in about 50% to 55% of
patients.
Answer: D
The carotid body origin is from the third branchial arch and
from neuro ectodermal derived in neural crest lineage. The
normal carotid body is located in the adventitia or periadventitial tissue at the bifurcation of the common carotid artery.
The gland is innervated by the glossopharyngeal nerve. Its
blood supply is derived predominantly from the external
carotid artery but can also come from the vertebral artery.
Carotid body tumor is a rare lesion of the neuroendocrine
system. Tumors involving the neural crest origin cells have
been referred to as part of a ganglioneuroma, glomus tumor,
or chemodectoma. Approximately 5% to 7% of carotid body
tumors are malignant. Although chronic hypoxemia has been
involved as a stimulus for hyperplasia of the carotid body,
approximately 35% of carotid body tumors are hereditary.
The risk of malignancy is greatest in young patients with
familial tumors. (See Schwartz 11th ed., pp. 918–919.)
Answer: B
An AAA is defined as a pathologic focal dilatation of the
aorta that is >30 mm or 1.5 times the adjacent diameter of
the normal aorta. Male aortas tend to be larger than female
aortas, and there is generalized growth of the aortic diameter
with each decade of life. Ninety percent of AAAs are infrarenal in location and have a fusiform morphology. There is
a higher predilection for juxtarenal and suprarenal AAAs
in women compared with men. Concomitant common iliac
and/or hypogastric artery aneurysms can be found in 20%
to 25% of patients. Although the etiology of most aortic
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aneurysms is atherosclerotic, clinically significant peripheral
occlusive disease is unusual and present in <10% of all cases.
(See Schwartz 11th ed., pp. 920–921.)
9. The ideal characteristics of an aneurysm for endovascular abdominal aortic aneurysm repair include all of the
following EXCEPT:
A. Neck length more than 20 mm.
CHAPTER 23
B. Neck diameter >18 mm, and <32 mm.
C. External iliac artery diameter >7 mm.
D. Aortic neck angle < 60 degrees.
Arterial Disease
Answer: A
Anatomic eligibility for endovascular repair is mainly based
on three areas: The proximal aortic neck, common iliac arteries, and external iliac and common femoral arteries, which
relate to the proximal and distal landing zones or fixation
site and the access vessels, respectively. The requirements
for proximal aortic neck are diameter of 18 to 28 mm and
the minimum length of 15 mm. Usually, multiple measurements of the diameter are taken along the length of the neck
to assess its shape. All diameter measurements are made from
mid wall to mid wall of the vessel. Secondary considerations
include the mural calcification < 50% circumference, luminal
thrombus < 50% circumference, and angulation < 45 degrees.
Presence of significant amount of any one of these secondary
features in combination with a relatively short proximal neck
may compromise successful short- and long-term fixation of
the stent graft and exclusion of the aneurysm. The treatable
diameters for common iliac arteries range from 8 to 20 mm,
and there should be at least 20 mm of patent artery of uniform diameter to allow adequate fixation. Finally, at least one
of two common femoral and external iliac arteries must be at
least 7 mm in diameter in order to safely introduce the main
delivery sheath. Slightly smaller iliac diameters may be tolerated depending on the specific device and in the absence of
severe tortuosity and calcific disease. Difficult access is one of
the main causes of increased procedural time and intraoperative complications. Using these criteria, approximately 60%
of all AAAs are anatomic candidates for endovascular repair.
(See Schwartz 11th ed., pp. 924–925.)
10. Which of the following is TRUE related to mesenteric
ischemia and mesenteric circulation?
A. Thrombosis is the commonest cause of mesenteric
ischemia in young patients.
B. Nonocclusive mesenteric ischemia most frequently
occurs in critically ill patients on vasopressors.
C. Duplex ultrasonography has accuracy of 50% for
detecting stenosis >70% in the superior mesenteric
artery (SMA).
D. Endovascular intervention is not indicated in patients
with asymptomatic occlusive disease of the mesenteric arteries.
Answer: B
Vascular occlusive disease of the mesenteric arteries is a relatively uncommon but potentially devastating condition that
generally presents in patient over 60 years of age. It is a three
times more frequent in women. There are three major mechanisms for visceral ischemia involving the mesenteric arteries:
Acute mesenteric ischemia, chronic mesenteric ischemia,
and nonocclusive mesenteric ischemia. The SMA is the most
commonly involved vessel in acute mesenteric ischemia.
Acute thrombosis occurs in patients with underlying mesenteric atherosclerosis, which typically involves the origin of
the mesenteric arteries while sparing the collateral branches.
In acute embolic mesenteric ischemia, the emboli typically
originate from the cardiac source. Nonocclusive mesenteric
ischemia is characterized by a low flow state and otherwise
normal mesenteric arteries and most frequently occurs in
critically ill patients on vasopressors. Duplex ultrasonography is a valuable noninvasive means of assessing the patency
of mesenteric vessels. A peak systolic velocity in the SMA of
>275 cm/s demonstrated a sensitivity of 92%, specificity of
96%, and overall accuracy of 96% for detecting >70% stenosis.
Similarly, duplex ultrasound had sensitivity and specificity of 87% and 82%, respectively with an accuracy of 82%
in predicting >70% stenosis in the celiac trunk. Endovascular treatment of mesenteric artery stenosis or short segment
occlusion by balloon dilatation or stent placement represent
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a less invasive therapeutic alternative to open surgical intervention particularly in patients whose medical comorbidities
place them at a higher operative surgical risk. Endovascular
therapy is also suited in patients with recurrent disease or
anastomotic stenosis following previous open mesenteric
revascularization. Prophylactic mesenteric revascularization
is rarely performed in the asymptomatic patient undergoing an aortic procedure for other indications. However, the
natural history of untreated chronic mesenteric ischemia may
justify revascularization in some minimally symptomatic or
asymptomatic patients if the operative risks are acceptable,
since the first clinical presentation may be acute intestinal
ischemia in as many as 50% of patients, with a mortality
rate that ranges from 15% to 70%. Mesenteric angioplasty
and stenting is particularly suited for this patient subgroup
given its low morbidity and mortality. (See Schwartz 11th ed.,
pp. 928–933.)
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Arterial Disease
11. Which of the following is TRUE about renal artery
disease?
A. Renal artery occlusive disease affects 5% to 10% of all
hypertensive patients in the United States.
B. The most common cause of renal artery occlusive
disease is atherosclerosis in 80% of patients followed
by fibromuscular dysplasia.
C. Renal artery revascularization is indicated in patients
with recurrent congestive heart failure or flash pulmonary edema not attributable to active coronary
ischemia in the presence of >70% stenosis of the renal
ar ter y.
D. All of the above.
Answer: D
Obstructive lesions of the renal artery can produce hypertension and it is reported in about 5% to 10% of all hypertensive patients in the United States. Approximately 80% of all
renal artery occlusive lesions are caused by atherosclerosis,
which typically involves a short segment of the renal artery
ostia and represent spillover disease from a severely atheromatous aorta. The second most common cause of renal
artery stenosis is fibromuscular dysplasia, which accounts for
20% of cases and is most frequently encountered in young,
often multiparous women. Fibromuscular dysplasia of the
renal artery presents a heterogeneous group of lesions that
can produce histopathological changes in the intima, media
or adventitia. The most common variety consists of medial
fibroplasia, in which thickened fibromuscular ridges alternate
with attenuated media producing the classic angiographic
“string of beads” appearance.
Indications for renal arterial revascularization include
≥70% stenosis of one or both renal arteries and at least one of
the following clinical criteria: Inability to adequately control
hypertension despite appropriate antihypertensive regime;
chronic renal insufficiency related to bilateral renal artery
occlusive disease or stenosis to a solitary functioning kidney;
dialysis-dependent renal failure in a patient with renal artery
stenosis but without another definite cause of end-stage renal
disease and recurrent congestive heart failure or flash pulmonary edema not attributable to active coronary ischemia. (See
Schwartz 11th ed., pp. 935–940.)
12. Which of the following is TRUE about atherosclerotic
aortoiliac occlusive disease?
A. Classified into three times with type I occurring
in 5% to 10% to patient extending into the lower
extremities below the knee.
B. Type II aortoiliac disease represents diffuse aortoiliac
disease above the inguinal ligament.
C. Type III represents multisegment occlusive disease
involving the aortoiliac area and extending to the
supra renal aorta.
D. Type I is more frequently found in men.
Answer: B
The distal abdominal aorta and the iliac arteries are common
sites affected by atherosclerosis. Based on the atherosclerotic
disease pattern, aortoiliac occlusive disease can be classified
into three types. Type I aortoiliac disease, which occurs in 5%
to 10% of patient, is confined to the distal abdominal aorta
and common iliac vessels. Due to the localized nature of this
type of aortic obstruction and formation of collateral blood
flow around the occluded segment, limb-threatening symptoms are rare in the absence of more distal disease. This type of
aortoiliac occlusive disease occurs in a relatively young group
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CHAPTER 23
Arterial Disease
of patients. Patients with type I disease pattern have a lower
incidence of hypertension and diabetes with a significant frequency of abnormal blood lipid levels particularly type IV
hyperlipoproteinemia. Type II aortoiliac disease represents
a more diffuse atherosclerotic progression and involves predominantly the abdominal aorta with disease extension into
the common iliac artery. This disease pattern affects approximately 25% of patients with aortoiliac occlusive disease.
Type III aortoiliac occlusive disease, which affects approximately 65% patient with aortoiliac occlusive disease, is widespread disease that is seen above and below the inguinal
ligament. Patients with multilevel disease are older, more
commonly with a male to female ratio of 6:1 and much more
likely to have diabetes, hypertension, and associated atherosclerotic disease involving cerebral, coronary, and basilar
arteries. (See Schwartz 11th ed., pp. 941–942.)
13. In regard to obturator bypass, which of the following is
TRUE?
A. It is indicated in patients with groin hematoma and
fever.
B. The conduit of Dacron, polytetrafluoroethylene
(PTFE), or autologous vein is tunneled through the
posteromedial portion of the obturator membrane.
C. The obturator artery and nerve pass in the anterome-
dial portion of the membrane.
D. 5-year patency of 57% has been reported.
14. In patients with acute limb ischemia, the following is
TRUE EXCEPT:
A. Immediate anticoagulation is indicated.
B. Hypercoagulable workup should be performed prior
to heparin initiation in all patients.
C. There is no clear superiority for thrombolysis over
surgery in terms of a 30-day limb salvage on mortality.
D. In the United States, surgery is used three- to five fold
more frequently than thrombolysis.
Answer: D
An obturator bypass is used to reconstruct arterial anatomy
in patients with a groin sepsis resulting from prior prostatic
grafting, intra-arterial drug abuse, growing neoplasm, or
damage from prior groin irradiation. This bypass can originate from the common iliac artery, external iliac artery, or
uninvolved limb of an aortobifemoral bypass. The conduit is
tunneled through the anteromedial portion of the obturator
membrane to the distal superficial femoral artery or popliteal
artery. The membrane must be divided sharply to avoid injury
to adjacent structures. Care must be taken to identify the
obturator artery and nerve that pass posterolaterally. There
have been very good results in terms of patency and limb salvage for obturator bypass. Some authors have reported 57%
5-year patency and 77% 5-year limb salvage rates, whereas
others have shown a higher rate of reinfection and low
patency requiring reintervention. (See Schwartz 11th ed.,
p. 946.)
Answer: B
Acute lower extremity ischemia manifesting with the five Ps:
Pain, pallor, paresthesia, paralysis, and pulselessness. The
sixth P, “poikilothermia” or “perishing cold,” is added. In the
absence of any significant contraindication, the patient with
an ischemic lower extremity should be immediately anticoagulated. This will prevent propagation of the clot into the unaffected vascular beds. Intravenous fluid should be started and
a Foley catheter inserted to monitor urine output. Baseline
labs should be obtained but hypercoagulable workup should
be performed only prior to initiation of heparin if there is a
sufficient suspicion. There is no clear superiority for thrombolysis over surgery in terms of a 30-day limb salvage on mortality. Access to each treatment option is a major issue in the
decision-making process, as time is often critical. National
registry data from the United States revealed that surgery is
used in three- to five fold more frequently than thrombolysis.
(See Schwartz 11th ed., p. 954-955.)
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15. In the absence of a suitable vein for lower extremity
bypass, prosthetic grafts can be used. Which of the following can be used to improve patency of prosthetic
grafts?
A. Altering the geometry at the distal anastomosis by
increasing the size of the arteriotomy
B. Bonding agents into the outer surface of the graft
C. Bonding anticoagulants to the conduit to improve
patency of the graft
D. Applying rings to the graft to improve patency
Answer: C
If a vein is unavailable, polytetrafluoroethylene (PTFE) or
Dacron can be used for above-knee bypass or in some cases
below the knee. The addition of rings to the PTFE did not
confer benefit in a single prospective, randomized clinical
trial. For infrageniculate prosthetic bypasses, use of a vein
patch, cuff, or other venous anastomotic modifications can
improve patency. Methods to improve prosthetic graft performance have consisted of altering the geometry at the distal anastomosis to get the benefit obtained with vein cuffs
and covalently binding agents onto the luminal surface with
anticoagulant, anti-inflammatory, and antiproliferative characteristics. A comparison of precuffed PTFE versus PTFE
with a vein cuff showed a 1 year and 2 years primary patency
rates were 52% and 49% in the precuffed group and 62% and
44% in the vein cuff group, respectively. Another approach
for improving outcomes using prosthetic for bypass grafts
involves binding anticoagulants to the conduit. The Gore propaten graft has heparin-bonded into the luminal surface of
the PTFE graft using Carmeda bioactive surface technology.
The heparin-binding does not alter the micro structure and
handling characteristic of the PTFE. A prospective randomized trial suggested that heparin-bonded Dacron or PTFE
was superior to plain PTFE for above-knee popliteal bypass.
The 3-year primary patency rate for the heparin-bonded graft
was 55% compared with 42% for the PTFE. But both of these
patency rates are inferior to greater saphenous vein grafts.
(See Schwartz 11th ed., p. 967-968.)
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Arterial Disease
16. The following is TRUE about fibromuscular dysplasia
EXCEPT:
A. The characteristic beaded appearance of fibromuscu-
lar dysplasia (FMD) is due to areas of medial thinning alternating with areas of stenosis.
B. The most commonly affected are the medium-sized
arteries.
C. The commonest involved arteries are the internal
carotid arteries.
D. FMD occurs most frequently in women.
Answer: C
FMD is a vasculopathy of uncertain etiology that is characterized by segmental arterial involvement. Histologically, fibrous
tissue proliferation, smooth muscle cell hyperplasia, and elastic fiber destruction alternate with mural thinning. The characteristic beaded appearance of fibromuscular dysplasia is
due to areas of medial thinning alternating with areas of stenosis. The most commonly affected arteries are the mediumsized arteries, including the renal, internal carotid, vertebral,
subclavian, mesenteric, and iliac arteries. The internal carotid
artery is the second most common site of involvement after the
renal arteries. FMD occurs most frequently in women (90%)
and is recognized at approximately 55 years of age. Only 10%
of patients with FMD will have complications attributable to
the disease. Pathologically, FMD is heterogeneous group of
four distinct types of lesions that are subgrouped based on
the predominant site of involvement within the vessel wall. Of
the four types (medial fibroplasia, intimal fibroplasia, medial
hyperplasia, and perimedial dysplasia), medial fibroplasia is
the most common pathological type, affecting the internal
carotid artery and the renal artery and occurring in 85% of
the reported cases. (See Schwartz 11th ed., pp. 972–973.)
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17. Which of the following is TRUE about adventitial cystic
disease of the popliteal artery?
A. It occurs in about 5% usually in the popliteal artery.
B. The disease affects men in a ratio approximately
of 5:1.
C. Patients present in their 40s and 50s.
D. Computed tomography angiogram (CTA) of the
lower extremities is the best diagnostic modality.
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Arterial Disease
Answer: B
The adventitial cystic disease of the popliteal artery was first
described in 1954. It is a rare arterial condition occurring at
an incidence of 0.1%, usually in the popliteal artery. This disease affects men in a ratio of approximately 5:1. The incidence
is approximately 1 in 1200 cases of claudication or 1 and 1000
peripheral arteriograms. The disease may affect other vascular sites, such as the femoral, external iliac, radial, ulnar,
and brachial arteries. The diagnosis should be considered in
young patients with a mass in a nonaxial vessel in proximity
to a related joint. The synovial-like mucin-filled cyst reside
in the subadventitial layer of the vessel wall and have a similar microscopical appearance to a ganglion cyst. Despite the
similarity and suggestion of a joint origin for these lesions,
histochemical markers have failed to link the cystic lining
to synovium. Patient presenting at a young age, with bilateral lower extremity claudication and minimal risk factors
for atheroma formation should be evaluated for adventitial
cystic disease as well as for popliteal artery entrapment syndrome and Buerger’s disease. Peripheral pulses may be present in the limb when extended, but then can disappear during
knee-joint flexion. Noninvasive studies may suggest arterial
stenosis with elevated velocities. Color-flow duplex scanning
followed by T2-weighted magnetic resonance imaging (MRI)
now appears to be the best diagnostic choice. Angiography
will demonstrate a smooth, well-defined, crescent-shaped
filling defect, the classic “scimitar” sign. There may be associated calcifications in the cyst wall and no other evidence
of atherosclerotic occlusive disease. The recommended treatments are excision of the cyst with the cystic wall, enucleation,
or simple aspiration when the artery is stenotic. Retention of
the cystic lining leads to continued secretion of the cystic
fluid and recurrent lesions. And 30% of patients who have
an occluded artery, resection of the affected artery, followed
by an interposition graft using autogenous saphenous vein, is
recommended. (See Schwartz 11th ed., p. 973.)
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Venous and Lymphatic Disease
1. All of the following regarding venous anatomy are TRUE
EXCEPT:
A. Veins are thin-walled, collapsible, and highly disten-
sible to a diameter several times greater than that in
the supine position.
B. The small saphenous vein (SSV) is accompanied by
the sural nerve.
C. The radial, ulnar, brachial, anterior tibial, posterior
tibial, peroneal, and popliteal veins usually exist as
paired veins.
D. The subclavian vein courses anterior to the anterior
scalene muscle.
Answer: C
Veins are thin-walled, highly distensible, and collapsible.
Their structure specifically supports the primary functions of
veins to transport blood toward the heart and serve as a reservoir to prevent intravascular volume overload.
Lower extremity veins are divided into superficial, deep,
and perforating veins. The superficial venous system lies
above the uppermost fascial layer of the leg and thigh and
consists of the great saphenous vein (GSV) and SSV and
their tributaries. The GSV originates from the dorsal pedal
venous arch and courses cephalad and medially, anterior to
the medial malleolus, entering the common femoral vein
approximately 4 cm inferior and lateral to the pubic tubercle.
The saphenous nerve accompanies the GSV medially from
the ankle to the level of the knee and supplies cutaneous sensation to the medial leg and ankle. The SSV originates laterally from the dorsal pedal venous arch and courses cephalad
in the posterior calf. Most often, it penetrates the popliteal
fossa, between the medial and lateral heads of the gastrocnemius muscle, to join the popliteal vein. The termination of the
SSV may be quite variable, however, with a proximal extension of the SSV (the vein of Giacomini) connecting with the
deep femoral vein or GSV. The sural nerve accompanies the
SSV laterally along its course and supplies cutaneous sensation to the lateral malleolar region.
The deep veins follow the course of major arteries in the
extremities. In the lower leg, paired veins parallel the course
of the anterior tibial, posterior tibial, and peroneal arteries,
to join behind the knee forming the popliteal vein. Venous
bridges connect the paired axial tibial veins in the lower leg.
The popliteal vein continues through the adductor hiatus to
become the femoral vein. In the proximal thigh, the femoral
vein joins with the deep femoral vein to form the common
femoral vein, becoming the external iliac vein at the inguinal
ligament.
As in the lower extremity, there are deep and superficial
veins in the upper extremity. Deep digital veins form the
palmar venous arches of the hand and empty into the paired
radial and ulnar veins. These follow the named arteries in the
arm and are known as the venae comitantes. They become the
brachial veins most often near the antecubital fossa and then
combine to contribute to forming the axillary vein. Superficial
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