Sabato 27 ottobre 2012 - Pacini Editore

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Fig. 2 The histological examination of the anterior descending
branch of the left coronary artery showed a more or less centric
haematoma, located between the coronary tunica media
and adventitia flattened and occluded the lumen (H&E 40x).
Fig. 3 The endofibrotic lesion was composed by myofibroblast
proliferation with distruped internal elastic membrane. (h&E
40x).
stenosis of external iliac arteries (EIAs). Surgery consisted of
shortening the artery with resection of the fibrotic lesions, and
enlargement of the arteries with a saphenous vein patch. Histological
examination of a 3.5 cm. long segment of EIAs showed
subendothelial plaque with abundant myofibroblast and a distruped
internal elastic membrane (Fig. 3). Because of the failing
of this treatment, an aorto-femoral bypass was performed. One
year after the last surgical treatment, the patient is asymptomatic
during exercise
Discussion. Lowenthal and Jacob first reported a case of lienal
vein aneurysm (LVA) in 1953 1 . LVA occurs predominantly in
women and the majority of LVAs are asymptomatic, incidental
findings, until complication as rupture, thrombosis or compression
of adjacent structures 2 . Rupture of LVA in pregnancy is a
very unusual and catastrophic event with a very high maternal and
fetal mortality rate. The present case is the first report with multiple,
true, saccular and fusiform aneurysms, with lethal rupture
in pregnancy. The precise etiology of LVA remains unknown,
because a few of the cases were studied. In the reported cases the
possible role of hormones leading to structural abnormalities of
the vascular wall has not been demonstrated, because of the rarity
of LVA, and so any peculiarity of circulation during pregnancy,
as hyperdynamic circulation. Different conditions have been associated
with LVA, including hepatic cirrhosis, portal hyperten-
CONGRESSO aNNualE di aNatOmia patOlOGiCa SiapEC – iap • fiRENzE, 25-27 OttOBRE 2012
sion, pancreatitis and pregnancy, but it can be idiopathic too 3 . In
all reported cases associated with pregnancy the aneurysm was
single; the shape, alterations of the vein wall and site were not
described. Aneurysms of the lienal artery are known more than
those of lienal vein as site, shape, evolution and management, because
these ones are diagnosed more frequently as incidental findings
during assessment for abdominal pain or other disorders 4 .
The present case is the first report of sudden death of a pregnant
woman and fetus from a rupture of maternal lineal vein aneurysm,
complication of multiple aneurysms with accurate histological
description (Fig. 2). Primary spontaneous coronary artery dissection
(PSCAD) has been defined as an intramural haematoma of
the media of the vessel wall (false lumen) which flattens the true
lumen, leading to blood flow obstruction and acute myocardial
ischaemia, in the absence of trauma or iatrogenic causes. PSCAD
is a rare event responsible for acute myocardial ischaemia and
was first described in 1931 in a 42 year old white woman who
died suddenly after experiencing chest pain. The disease is also
know as dissecting aneurysm, intramural haemorrhage or haematoma.
When secondary causes, such as aortic dissection, trauma,
coronary angiography,angioplasty, or surgical manipulations are
excluded 5-7 , the aetiology of spontaneous coronary artery dissection
remains uncertain and the disease is considered “primary”.
Most of the patients do not have risk factors for coronary artery
disease, and hypertension has rarely been reported 5 . On the basis
of epidemiological data, the condition occurs in one in 20 000 to
30 000 deliveries and has a high mortality rate for both mother and
child. The aetiology of PSCAD is unknown. The high incidence
in pregnancy and puerperium indicates hormonal changes and
haemodynamic stress as possible factors. Heefner 8 hypothesised
a two step process for the pathogenesis of SCAD. Firstly, the haemodynamic
stress of pregnancy leads to an initial intimal rupture.
This is followed by a delayed bleeding in the tunica media caused
by the clotting changes that occur during the puerperium 8 . A
primary rupture of the vasa vasorum into the vessel wall has been
noted in some cases. Antiphosholipid antibodies may have a role
in the pathogenesis of dissection by causing endothelial dysfunction,
although such an association with spontaneous coronary
artery dissection has not been reported 9 . Arterial endofibrosis
(E) is an uncommon arterio-occlusive condition that affects highperformance
endurance athletes, cyclists in particular 10 11 . Patients
typically present with rapid fatigue and thigh claudication, which
resolves quickly postexercise. Most patients are found to have
a simple focal stenosis secondary to fibrotic plaques within the
external iliac artery. The epidemiology of external iliac artery E
is not well described. It has been reported that 20% of top-level
cyclists will develop sports-related flow limitations of the EIAs 12 .
E is most often described in cyclists, but cases have been reported
in other groups of endurance athletes including triathletes, runners,
cross-country skiers, rowers, and rugby players 10 11 . Patients do
not necessarily need to be professionals. E development has been
linked to both anatomic and mechanical factors. Studies of affected
athletes have noted tethering of the EIA to the psoas muscle
in 50% to 64% of cases 10 12 13 . Further, the middle portion of the
EIA is subject to both high shear forces and high blood flows
during maximal exercise. A variety of etiologic factors have been
suggested, including external compression due to psoas muscle
hypertrophy, high-flow conditions due to increased cardiac output
and adaptive systolic hypertension, and kinking/tortuosity.
Lengthening of the EIA is noted in E patients as the arteries to the
psoas muscle in the central portion of the vessel create an immobile
segment “working against” the relatively mobile adjacent segments
of EIA. The subsequent excess length predisposes the artery
to repetitive kinking during the pedaling process 13 . This results in
repeated trauma to the arterial wall, which can cause an inflammatory
reaction 14 . The endofibrotic lesions have been reported
to be composed by loose connective tissue matrix with moderate
to high cellularity consisting of spindle and stellate shaped cells.