Aortic Aneurysm: DR Rahul C
Aortic Aneurysm: DR Rahul C
Aortic Aneurysm: DR Rahul C
Dr rahul c
ANATOMY
• The aorta is the ultimate conduit, carrying, in an average lifetime,
almost 200 million litres of blood to the body.
IV. Graft wall ( fabric ) porosity ( <30 days after graft placement )
Surgery
• Ascending aorta
• Themain principle of surgery for ascending aortic
aneurysms is that of preventing the risk of dissection or
rupture by restoring the normal dimension of the
ascending aorta.
• If the aneurysm is proximally limited to the sinotubular
junction and distally to the aortic arch, resection of the
aneurysm and supra-commissural implantation of a
tubular graft is performed under a short period of
aortic clamping, with the distal anastomosis just below
the aortic arch.
• If the aneurysm extends proximally below the
sinotubular junction and one or more aortic
sinuses are dilated, the surgical repair is guided
by the extent of involvement of the aortic
annulus and the aortic valve.
• Surgical mortality for isolated elective
replacement of the ascending aorta (including
the aortic root) ranges from 1.6–4.8% and is
dependent largely on age and other well-known
cardiovascular risk factors at the time of
operation.
• Descending aorta
• The surgical approach to the descending aorta is
a left thoracotomy between the fourth and
seventh intercostal spaces, depending on the
extension of the aortic pathology .
• Established methods for operation of the
descending aorta include the left heart bypass
technique, the partial bypass, and the operation
in deep hypothermic circulatory arrest.
• Thoraco-abdominal aorta
• When the disease affects both the descending thoracic
and abdominal aorta, the surgical approach is a left
thoracotomy extended to paramedian laparotomy.
• Therisk of paraplegia after thoraco-abdominal repair is
in the range of 6–8%.
• Measures to reduce this include permissive systemic
hypothermia (34degree C), reattachment of distal
intercostal arteries between T8 and L1, and the pre-
operative placement of cerebrospinal fluid drainage.
• Abdominal aorta
• Open abdominal aortic repair usually involves a
standardmedian laparotomy, but may also be
performed through a left retroperitoneal approach.
• The aneurysmal aorta is replaced either by a tube or
bifurcated graft, according to the extent of aneurysmal
disease into the iliac arteries.
• Theexcluded aneurysmis not resected, but is closed
over the graft, which has a haemostatic effect and
ensures that the duodenum is not in contact with the
graft, as this may lead to erosion and a possible
subsequent aorto-enteric fistula.
EVAR VS OSR
• For a subset of AAA patients, all being
anatomically and physiologically eligible for
both conventional EVAR and open repair, a
head-to-head comparison of the two
techniques was prompted
• In individuals considered fit for conventional surgery, EVAR
was associated with lower short-term mortality than OSR.
• Class I
• Class I
• Class I
• 5. For patients with isolated aortic arch aneurysms less than 4.0 cm
in diameter, it is reasonable to reimage using computed
tomographic imaging or magnetic resonance imaging, at 12-month
intervals, to detect enlargement of the aneurysm. (LOE: C)
• Class I
•
• Understanding of genetic alterations resulting in aneurysms
may suggest avenues to pharmacologic therapy (with
conventional drugs designed to shortcircuit the mechanism
of aneurysm formation and progression).