DOI:10.2214/AJR.07.2370
AJR 2007; 189:712-719
© American Roentgen Ray Society
Vascular Ehlers-Danlos Syndrome: Imaging Findings
Massimo Zilocchi1,2,
Thanila A. Macedo1,
Gustavo S. Oderich3,
Terri J. Vrtiska1,
Pietro R. Biondetti2 and
Anthony W. Stanson1
1 Department of Radiology, Mayo Clinic, 200 First St., SW, Rochester, MN
55905.
2 Present address: Department of Radiology, Fondazione IRCCS, Ospedale Maggiore
Policlinico, Mangiagalli Regina Elena, Milan, Italy.
3 Division of Vascular Surgery, Mayo Clinic, Rochester, MN.
Received November 28, 2006;
accepted after revision April 7, 2007.
Address correspondence to T. A. Macedo
(macedo.thanila{at}mayo.edu).
Abstract
OBJECTIVE. Vascular Ehlers-Danlos syndrome (EDS), formerly known as
EDS type IV, is an autosomal dominant disorder characterized by fragility of
medium and large arteries due to type III procollagen deficiency. Our purpose
was to review the imaging findings in a cohort of patients with a diagnosis of
vascular EDS.
MATERIALS AND METHODS. The radiologic, surgical, and genetic
databases at a single multispecialty medical practice were reviewed for a
35-year period between 1971 and 2006. Thirty-three patients with a clinical
diagnosis of vascular EDS were identified. Imaging studies were available for
28 patients, 13 men and 15 women, with a mean age of 39.8 ± 16 years at
the time of diagnosis. A vascular radiologist reviewed a total of 189 imaging
examinations: 87 CT, 27 MRI, 59 sonography, and 16 angiography.
RESULTS. Vascular abnormalities were present in 22 (78%) of 28
patients. Arterial abnormalities included 41 aneurysms, 19 dissections, 12
ectasias, and 10 occlusions. There was one splenic vein aneurysm and one
carotid cavernous fistula. Six patients had a total of 10 parenchymal infarcts
involving the brain (n = 5), kidney (n = 3), and spleen
(n = 2). Nine patients had 10 hemorrhagic events, five related to
spontaneous vascular rupture and five associated with interventional or
surgical procedures. Six patients had 13 nonvascular findings.
CONCLUSION. The most common findings were arterial aneurysms and
dissections, followed by arterial ectasias and occlusions. Life-threatening
complications included hemorrhage and infarcts.
Keywords: Ehlers-Danlos syndrome • vascular imaging
Introduction
Ehlers-Danlos syndrome (EDS) is a rare heterogeneous group of connective
tissue disorders with distinct inheritance patterns and biochemical defects.
The estimated prevalence is one in every 25,000 births
[1]. Vascular EDS, formerly
known as EDS type IV, is an autosomal dominant disorder caused by heterozygous
mutations in the COL3A1 gene encoding for type III procollagen
[1–7].
The clinical implication of a structural defect in type III procollagen is
excessive tissue fragility predisposing to premature arterial, intestinal, or
uterine rupture [8]. Unlike the
other types of EDS, vascular EDS carries a poor prognosis because of the risk
of life-threatening arterial rupture.
The diagnosis of vascular EDS is challenging. Patients often have subtle
phenotypic features and are unaware of the diagnosis at the time of their
first vascular complication
[9]. From the radiologist's
perspective, prompt diagnosis of patients with vascular EDS is of paramount
importance for at least two reasons. First, invasive studies such as
conventional angiography and other percutaneous interventions should be
avoided because of the excessive risk of arterial tear or dissection due to
catheter-related trauma [10,
11]. Therefore, noninvasive
imaging studies such as sonography, CT angiography (CTA), and MR angiography
are preferred over conventional angiography. Second, familiarity with the
imaging findings of vascular EDS is important because the diagnosis may first
be suspected on the basis of radiologic findings. The purpose of this study
was to discern the imaging findings in a cohort of 28 patients with a clinical
diagnosis of vascular EDS.
Materials and Methods
Patients
We reviewed the radiologic, surgical, and medical genetics database
collected at a single multispecialty medical practice for a 35-year period
between 1971 and 2006. Thirty-three patients were identified with the clinical
diagnosis of vascular EDS. The study was approved by the institutional review
board.
Imaging studies were available in 28 patients, who formed our study
population. There were 13 men and 15 women with mean age of 39.8 ± 16
years (range, 17–81 years) at the time of vascular EDS diagnosis. Eight
women were nulliparous, seven were multiparus. The clinical characteristics
(Table 1) and outcome were
previously reported [12], and
herein we concentrate on imaging findings.
The clinical diagnosis of vascular EDS was made on the basis of at least
two of four major diagnostic criteria, as defined by the revised nosology of
Villefranche in 1997 [2]. These
criteria include thin, translucent skin; extensive bruising; characteristic
facial features (thin, pinched nose and prominent eyes); and history of
arterial, intestinal, or uterine fragility
[2]. Laboratory confirmation of
the diagnosis was made in 22 patients by the presence of structurally abnormal
type II procollagen using a culture of dermal fibroblasts or through the
detection of COL3A1 gene mutation. Six patients had the diagnosis
established solely on the basis of clinical criteria. Of the 28 patients
included in the study, only nine (32%) had an established diagnosis before
presentation at our institution.
Imaging Technique and Analysis
Each of the 28 patients underwent at least one imaging study, including CT,
CTA, MRI, MR angiography, sonography, or conventional angiography. Thirteen
patients had three or more studies, 10 had two, and five had one. The mean
number of examinations per patient was 6.7 ± 8.5 (range, 1–34
examinations). Imaging findings were divided into one of two categories:
vascular and nonvascular. Vascular complications were defined as arterial or
venous rupture, dissection, aneurysm, and organ infarct or rupture. A vascular
radiologist reviewed a total of 189 examinations
(Table 1). Multiple studies in
a given patient were reviewed at the same time.
A variety of equipment and protocols were used during a time period
involving more than three decades of imaging advances. Conventional
angiography was performed in standard technique, with most examinations
acquired through femoral artery access. CT was performed with a section
thickness ranging from 1.25 to 10 mm. Sixteen CT examinations were performed
without IV contrast material. CTA was performed with a section thickness
ranging from 0.6 to 3 mm during the arterial phase of contrast triggered by
automatic bolus tracking and injection of 100–140 mL of iodinated
contrast material. MRI was performed, including T1- and T2-weighted sequences,
in 27 examinations and 3D time-of-flight MR angiography with gadolinium
enhancement in 17 cases.
Results
Vascular abnormalities were present in 22 of 28 patients. Of these
patients, three (3/22) had the vascular abnormalities on previous outside
examinations, which were not available for our review. Two (2/22) patients
presented with hemorrhagic complications without other vascular findings. The
remaining 17 of 22 patients had vascular findings as summarized in
Table 2. Only nonvascular
findings were found in two of 28 patients. No abnormalities were found in four
(14.3%) of 28 patients.
Vascular Findings
A total of 83 vascular findings, including ectasia (n = 12),
aneurysm (n = 42), dissection (n = 19), and occlusion
(n= 10), were noted in 17 of the 28 patients. Fifty vascular
abnormalities occurred in nine men and 33 occurred in eight women, with an
average number of 5.5 lesions in men and 4.1 lesions in women. The spectrum
and distribution of vascular findings are summarized in
Figure 1. Vascular
abnormalities were most commonly seen in the visceral (n = 26), iliac
(n = 22), and head and neck (n = 16) locations. However, the
most common location of abnormalities considering the overall number of
patients was visceral arteries (eight patients), head and neck (eight
patients), and aorta (eight patients). The single vessel with the largest
number of lesions was the iliac artery: 13 abnormalities were noted in three
men and nine in two women (one of whom was pregnant). Most patients (13/17)
with vascular findings had multiple vascular abnormalities (range, 2–18
abnormalities) (Fig. 2); three
patients had more than nine abnormalities. Other vascular findings included
spontaneous carotid cavernous fistula and acute deep venous thrombosis of the
calf veins. Fifty-eight examinations (30.7%) showed no abnormalities.
View larger version (42K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1 —Spectrum and distribution of vascular findings in
Ehlers-Danlos syndrome: total of 83 abnormal vascular findings including
ectasia, aneurysm, dissection, and occlusion. DTA = descending thoracic aorta,
IMA = inferior mesenteric artery, SFA = superior femoral artery, SMA =
superior mesenteric artery.
|
|
View larger version (90K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2 —22-year-old woman with common iliac and hypogastric artery
aneurysms. CT angiogram with 3D reconstruction reveals dissecting aneurysm of
right common iliac artery (thin arrow) as well as aneurysms of right
hypogastric artery and left common iliac artery (thick arrows).
|
|
Vascular Complications
Six patients had a total of 10 parenchymal infarcts involving the brain
(n =5), kidney (n = 3), and spleen (n = 2). Seven
patients had 10 hemorrhagic events, including five spontaneous vascular
ruptures and five hemorrhagic events associated with interventional or
surgical procedures. The spontaneous vascular ruptures consisted of, in one
patient each, subcapsular and intraparenchymal splenic hematoma, hemothorax,
intraparenchymal lung hemorrhage, splenic vein–ruptured aneurysm
(Fig. 3A), and inferior
epigastric artery rupture (Fig.
3B). Two patients had hemorrhagic events after catheterization.
These included a perforation of the internal mammary artery with associated
hemomediastinum (Fig. 3C) and a
perforation of the carotid artery during attempts to occlude a carotid
cavernous fistula. The other three hemorrhagic complications included a
subcapsular hepatic hematoma after cholecystectomy, a small perihepatic
hematoma after liver biopsy, and a prolonged groin hematoma after superficial
femoral artery graft placement in one patient each.
View larger version (132K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3B —51-year-old woman with vascular Ehlers-Danlos syndrome. Three
days later, patient developed spontaneous rupture of left inferior epigastric
artery with active bleeding and a rectus sheath hematoma shown in this CT
image.
|
|
View larger version (142K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3C —51-year-old woman with vascular Ehlers-Danlos syndrome.
Patient underwent coil embolization complicated by perforation of left
internal mammary artery, extravasation of contrast material, and development
of hemomediastinum (arrow), shown in this radiograph obtained during
conventional angiography.
|
|
Progression of Vascular Disease
Five patients had serial studies obtained over a period of 3–7 years.
A summary of the imaging findings is outlined below:
Patient 1—An 81-year-old man with a clinical diagnosis of
vascular EDS and no biochemical or molecular confirmation had progression of
multiple aneurysms over a 3-year period. A 5-cm ascending thoracic aorta and
distal arch aneurysm increased to a maximum diameter of 6 cm during a 19-month
follow-up, prompting surgical repair. The thoracoabdominal aorta at the
diaphragmatic level enlarged from 4.1 to 5 cm over 33 months, and then to 5.7
cm during the next 3 months. An internal iliac artery aneurysm enlarged from 3
to 4 cm, and the deep femoral artery enlarged from 1.1 to 1.4 cm over 33
months. Bilateral common iliac artery aneurysms remained stable in size. A new
6-cm paraanastomotic aneurysm developed in the distal anastomosis of a
previously placed femoropopliteal graft, and a 2.1-cm left subclavian aneurysm
increased to 2.7 cm in 6 months.
Patient 2—A 47-year-old man with a clinical and laboratory
diagnosis of vascular EDS presented with spontaneous renal artery dissection
and renal infarcts. Five days after presentation he developed dissections of
the gastroduodenal and contralateral renal and splenic arteries with
associated splenic infarct. Repeat examination 3 days later showed new
dissection of the celiac artery, dissection and dilatation of the common
hepatic artery, and occlusion of the gastroduodenal branch (Figs.
4A,
4B, and
4C). Three-year follow-up
imaging revealed new dissection and ectasia of both the common and the
external iliac arteries.
Patient 3—A 34-year-old woman with clinical and laboratory
evidence of vascular EDS presented with a 1.2-cm celiac axis saccular aneurysm
(Fig. 5A) and developed
near-complete thrombosis over a 2-day period. Follow-up examination 2 months
later showed recanalization of the celiac axis aneurysm and resolution of the
thrombus. This patient also had bilateral common iliac artery aneurysms, right
internal iliac ectasia, and a left internal iliac aneurysm
(Fig. 5B) that developed a
small amount of mural thrombus over 2 years.
View larger version (72K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 5A —34-year-old woman with vascular Ehlers-Danlos syndrome. CT
angiography of abdomen with volume-rendered 3D reconstruction shows 1.2-cm
saccular aneurysm (arrow) arising from inferior wall of celiac
axis.
|
|
View larger version (106K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 5B —34-year-old woman with vascular Ehlers-Danlos syndrome. CT
angiography of pelvis with volume-rendered reconstruction shows bilateral
common iliac arteries, left internal iliac aneurysm, and right internal iliac
ectasia.
|
|
View larger version (128K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4D —47-year-old man with multiple vascular abnormalities.
Enhanced CT scan of pelvis 3 years later shows patient has developed new
dissection and ectasia of left common and external iliac arteries
(arrow).
|
|
Patient 4—A 65-year-old man with clinical and laboratory
diagnoses of vascular EDS and a history of aortobifemoral and femoropopliteal
bypasses developed multiple aneurysms. These included a 6-cm femoral
anastomotic aneurysm and a 1.3-cm internal iliac aneurysm over a 17-year
interval. In addition, at an 8-month follow-up multiple aneurysms were noted,
including bilateral fusiform aneurysms of the vertebral arteries, ectasia of
the ascending thoracic aorta, a 1.6-cm celiac artery aneurysm, a 1.2-cm
proximal superior mesenteric artery aneurysm, a 1.8-cm mid superior mesenteric
artery fusiform thrombosed aneurysm, bilateral renal artery aneurysms, and a
2.5-cm femoral anastomotic aneurysm.
Patient 5—A 33-year-old woman with clinical and laboratory
diagnoses of vascular EDS developed dissection of the left renal artery and
cortical infarcts over an 8-month interval. In addition, 1 month later she
developed ectasia of the previously dissected main renal artery and also a new
dissection in the contralateral renal artery.
Nonvascular Findings
Six patients had 13 nonvascular findings, including three cavernous
hemangiomas, two cases of diverticulitis, and one case each of cholecystitis,
sclerosing cholangitis, cholangiocarcinoma, focal nodular hyperplasia of the
liver, lumbar vertebral body hemangioma, recent pancreatitis, and ulcerative
colitis. One patient had partial colectomy because of ruptured sigmoid
colon.
Discussion
Ehlers [13] and Danlos
[14] described the classic
features of skin hyperelasticity and joint hypermobility in the early 1900s.
Since then, a variety of terms have been used to describe the vascular
manifestations of EDS. Sack in 1936 first introduced the term "status
dysvascularis" [15], and
Barabas [3] in 1967 described
the vascular or arterial–ecchymotic type. The disorder was then named
after the two physicians as "Sack-Barabas syndrome." The first
classification system of EDS defined 11 types, of which "type IV
EDS" was used to describe patients with increased vascular fragility. A
more recent consensus conference has simplified this old classification system
into six distinct varieties: classic, hypermobility, vascular, kyphoscoliosis,
arthrochalasia, and dermatosparaxis types. Therefore, the current recommended
nomenclature is "vascular EDS."
Vascular EDS is rare and accounts for fewer than 4% of all EDS patients
[6,
7]. Patients often have subtle
and variable phenotypic features as compared with patients with other forms of
EDS. The clinical diagnosis can be established on the basis of major
diagnostic criteria. Excessive bruising and a tendency to form hematomas is
the most common sign and may be the first clue to the diagnosis in children
and adolescents. Skin hyperelasticity is usually not present. Instead, nearly
80% of patients have thin, translucent skin with highly visible superficial
veins on the chest, shoulders, and abdomen
[12]. A characteristic facial
appearance—thin, delicate, and pinched nose; thin lips; and prominent
bones and eyes—is noticed in 30% or fewer of vascular EDS patients
[1,
8,
12]. Although the clinical
diagnosis of vascular EDS should have a high specificity, laboratory
confirmation is strongly recommended to confirm the diagnosis. The preferred
strategy for definitive diagnosis is direct assessment of procollagen III
deficiency through culture of dermal fibroblasts, which requires skin biopsy.
Alternatively, analysis of the DNA sequence can determine the presence of
COL3A1 gene mutation.
Vascular EDS is of special interest to the radiologist because it can be
characterized by widespread vascular changes, including aneurysms,
dissections, ruptures, and fistula formation. The disorder can affect medium
and large arteries in any location. Because patients are frequently unaware of
the diagnosis at the time of their first vascular complication, vascular EDS
should be suspected in young patients presenting with unusual or extensive
vascular findings.
Previous case reports have discussed involvement of the thoracic and
abdominal aorta, the celiac axis, and the splenic, hepatic,
pancreaticoduodenal, renal, iliac, carotid, cervical, and intracranial
arteries
[16–23].
In our study, the main characteristic in patients with vascular EDS is the
tendency to have multiple abnormalities in various vascular segments at a
relatively young age. In fact, of the patients with vascular abnormalities,
most (13/17) had more than two vascular abnormalities, and in three cases
there were more than nine abnormalities in the same patient. Although serial
examinations were available in only five patients, all of them showed
progression of vascular findings: aneurysm enlargement and development of
secondary complications such as dissections, occlusions, or spontaneous
ruptures. The most common vascular segments affected, in decreasing order of
frequency, were the abdominal visceral arteries, iliac arteries, thoracic and
abdominal aorta, lower limb, carotid, vertebral, subclavian, pulmonary, and
cerebral arteries.
In our experience, the most common complications were hemorrhagic events
and parenchymal infarcts affecting the cerebral, renal, and splenic
circulation. Vascular ruptures are common and may result from minor trauma or
be iatrogenic or spontaneous in nature. In a recent article, Boutouyrie et al.
[24] described the geometric
and elastic properties of conducting arteries to assess the pathogenesis of
vascular complications in patients with vascular EDS. There was abnormally low
intima–media thickness, which generates high wall stress and potentially
increases the risk of dissection and rupture
[24]. This is shown in our
study by the occurrence of spontaneous ruptures of the inferior epigastric
artery, spontaneous subcapsular and intraparenchymal splenic hematoma, splenic
vein aneurysm rupture, and pulmonary hemorrhage with hemothorax.
The role of routine noninvasive imaging and periodic arterial screening has
not been evaluated in vascular EDS patients
[25]. However, we found that
the use of noninvasive imaging such as sonography, CTA, and MR angiography
readily diagnosed and identified early complications in vascular EDS.
Conventional angiography was used more frequently at the beginning of our
experience and was associated with hemorrhagic complications in two patients.
We currently have substituted noninvasive techniques for conventional
angiography because of the higher complication rates of angiography due to
vascular wall fragility [10,
11] and the improved
resolution available with noninvasive imaging examinations. Conventional
angiography is currently used as part of a planned interventional procedure,
such as coil embolization of bleeding arteries in remote locations.
In conclusion, patients with vascular type EDS usually have multiple
vascular abnormalities, with aneurysms being the most common, followed by
dissection and ectasia involving the visceral arteries, aorta, and head and
neck most frequently. Our series showed that the vascular abnormalities are
progressive; therefore, noninvasive imaging should be considered not only as a
diagnostic tool but also as a valuable tool in the follow-up of identified
vascular lesions.
References
- Byers PH. Ehlers-Danlos syndrome. In: Rimoin DL, Connor JM, Pyeritz
RE, eds. Emery and Rimoin's principles and practice of medical
genetics, 3rd ed., vol. 1. New York, NY:
Churchill Livingstone, 1997:1067
-1081
- Beighton P, De Paepe A, Steinmann B, Tsipouras P, Wenstrup RJ.
Ehlers-Danlos syndromes: revised nosology, Villefranche, 1997. Am J
Med Genet 1998; 77:31
-37[CrossRef][Medline]
- Barabas AP. Heterogeneity of the Ehlers-Danlos syndrome:
description of three clinical types and a hypothesis to explain the basic
defect(s). Br Med J 1967;2
: 612-613[Free Full Text]
- Barabas AP. Vascular complications in the Ehlers-Danlos syndrome,
with special reference to the "arterial type" or Sack's syndrome.
J Cardiovasc Surg 1972;13
: 160-167[Medline]
- Pope FM, Martin GR, Lichtenstein JR, et al. Patients with
Ehlers-Danlos syndrome type IV lack type III collagen. Proc Natl
Acad Sci U S A 1975; 72:1314
-1316[Abstract/Free Full Text]
- Germain DP, Herrera-Guzman Y. Vascular Ehlers-Danlos syndrome.
Ann Genet 2004;47
: 1-9[Medline]
- Germain DP. Clinical and genetic features of vascular Ehlers-Danlos
syndrome. Ann Vasc Surg 2002;16
: 391-397[CrossRef][Medline]
- De Paepe A, Malfait F. Bleeding and bruising in patients with
Ehlers-Danlos syndrome and other collagen vascular disorders. Br J
Haematol 2004; 127:491
-500[CrossRef][Medline]
- Pepin M, Schwarze U, Superti-Furga A, Byers PH. Clinical and
genetic features of Ehlers-Danlos syndrome type IV, the vascular type.
N Engl J Med 2000;342
: 673-680[Abstract/Free Full Text]
- Driscoll SH, Gomes AS, Machleder HI. Perforation of the superior
vena cava: a complication of digital angiography in Ehlers-Danlos syndrome.
AJR 1984; 142:1021
-1022[Free Full Text]
- Slingenberg EJ. Complications during intravascular diagnostic
manipulations in the Ehlers-Danlos syndrome. Neth J
Surg 1980; 32:56
-58[Medline]
- Oderich GS, Panneton JM, Bower TC, et al. The spectrum, management
and clinical outcome of Ehlers-Danlos syndrome type IV: a 30-year experience.
J Vasc Surg 2005;42
: 98-106[CrossRef][Medline]
- Ehlers E. Cutis laxa neigung zu haemorrhagien in der haut, lokerung
mehrerer artikulationen. Dermatol Ztschr1901; 8:173
-174
- Danlos M. Un cas de cutis laxa avec tumeurs par contusion chronique
des coudes et des genoux (xanthome juvenile pseudodiabetique de MM Hallopeault
Mace de Lepinari). Bull Soc Franc Dermatol Syph1908; 19:70
- Sack G. Status dysvascularis, ein Fall von besonderer
Zerreiblichkeit der Blutgefabe. Dtsch Arch klink Med1936; 178:663
-669
- Karkos CD, Prasad V, Mukhopadhyay U, Thomson GJ, Hearn AR. Rupture
of the abdominal aorta in patients with Ehlers-Danlos syndrome. Ann
Vasc Surg 2000; 14:274
-277[CrossRef][Medline]
- Parfitt J, Chalmers RTA, Wolfe JHN. Visceral aneurysms in
Ehlers-Danlos syndrome: case report and review of the literature. J
Vasc Surg 2000; 31:1248
-1251[CrossRef][Medline]
- Casana R, Nano G, Dalainas I, Tealdi DG. Endovascular treatment of
hepatic artery aneurysm in a patient with Ehlers-Danlos syndrome: case report.
Int Angiol 2004;23
: 291-295[Medline]
- Imamura A, Nakamoto H, Inoue T, et al. Ruptured dissecting aneurysm
in bilateral iliac arteries caused by Ehlers-Danlos syndrome type IV: report
of a case. Surg Today 2001;31
: 85-89[CrossRef][Medline]
- Schievink WI, Piepgras DG, Earnest F, Gordon H. Spontaneous
carotid-cavernous fistulae in Ehlers-Danlos syndrome type IV. J
Neurosurg 1991; 74:991
-998[Medline]
- Nekrysh SY. Association between heritable connective tissue
disorders and intracranial aneurysms. Surg Neurol2000; 54:77
-78[Medline]
- Kato T, Hattori H, Yorifuji T, Nakahata T. Intracranial aneurysms
in Ehlers-Danlos syndrome type IV in early childhood. Ped
Neurol 2001; 25:336
-339[CrossRef][Medline]
- Yost BA, Vogelsang JP, Lie JT. Fatal hemoptysis in Ehlers-Danlos
syndrome: old malady with a new curse. Chest1995; 107:1465
-1467[CrossRef][Medline]
- Boutouyrie P, Germain DP, Fiessinger JN, Laloux B, Perdu J, Laurent
S. Increased carotid wall stress in vascular Ehlers-Danlos syndrome.
Circulation 2004;109
: 1530-1535[Abstract/Free Full Text]
- Bergqvist D. Ehlers-Danlos type IV syndrome: a review from a
vascular surgical point of view. Eur J Surg1996; 162:163
-170[Medline]
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
Top
Abstract
Introduction
