The document discusses aneurysms and aortic dissections. It defines an aneurysm as an abnormal dilatation of a blood vessel wall due to weakening. Aortic dissections occur when the inner layer of the aorta tears, allowing blood to surge between the layers. Risk factors include hypertension, smoking, genetics. Symptoms include chest pain. Diagnosis involves imaging tests like ultrasound, CT, or MRI. Treatment depends on location but may include open or endovascular surgery to repair or replace the damaged vessel.

1. NAME – NEHA DIWAN

2.  An aneurysm is defined as a permanent
abnormal dilatation of a blood vessel occurring
due to congenital or acquired weakening or
destruction of the vessel wall.
 Most commonly, aneurysms involve large elastic
arteries, especially the aorta and its major
branches.
 Aneurysms can cause various ill effects such as
thrombosis and thromboembolism, alteration in
the flow of blood, rupture of the vessel and
compression of neighbouring structures.

3.  An aortic dissection is a
serious condition in which
the inner layer of the
aorta, the large blood
vessel branching off the
heart, tears. Blood surges
through the tear, causing
the inner and middle
layers of the aorta to
separate (dissect). If the
blood-filled channel
ruptures through the
outside aortic wall, aortic
dissection is often fatal.

4.  The term dissecting aneurysm is applied for a
dissecting haematoma in which the blood enters
the separated (dissected) wall of the vessel and
spreads for varying distance longitudinally.
 The most common site is the aorta and is an
acute catastrophic aortic disease.
 The condition occurs most commonly in men in
the age range of 50 to 70 years.
 In women,dissecting aneurysms may occur
during pregnancy.

5.  The pathogenesis of dissecting aneurysm is explained on the basis of
weakened aortic media.
 Various conditions causing weakening in the aortic wall resulting in dissection are
as under:
 i) Hypertensive state -
 About 90% cases of dissecting aneurysm have hypertension which predisposes
such patients to degeneration of the media in some questionable way.
 ii) Non-hypertensive cases -
 These are cases in whom there is some local or systemic connective tissue
disorder e.g.
 a) Marfan’s syndrome, an autosomal dominant disease with genetic defect in
fibrillin which is a connective tissue protein required for elastic tissue formation.
 b) Development of cystic medial necrosis of Erdheim, especially in old age.
 c) Iatrogenic trauma during cardiac catheterisation or coronary bypass surgery.
 d) Pregnancy, for some unknown reasons.

6. Once medial necrosis has occurred,
haemodynamic factors,
chiefly hypertension, cause tear in the intima and
initiate the dissecting aneurysms.
The media is split at its weakest point by the
inflowing blood.
An alternative suggestion is that the medial
haemorrhage from the vasa vasorum occurs first
and the intimal tear follows it.
Further extension of aneurysm occurs due to entry
of blood into the media through the intimal tear.

7.  Dissecting aneurysm differs from atherosclerotic and
syphilitic aneurysms in having no significant dilatation.
 Therefore, it is currently referred to as ‘dissecting
haematoma’. Dissecting aneurysm classically begins in the
arch of aorta. In 95% of cases, there is a sharply incised,
transverse or oblique intimal tear, 3-4 cm long, most often
located in the ascending part of the aorta.
 The dissection is seen most characteristically between the
outer and middle third of the aortic media so that the
column of blood in the dissection separates the intima and
inner two-third of the media on one side from the outer one-
third of the media and the adventitia on the other.
 The dissection extends proximally into the aortic valve ring
as well as distally into the abdominal aorta

8.  Occasionally, the dissection may extend into the
branches of aorta e.g. into the arteries of the neck,
coronaries, renal, mesenteric and iliac arteries.
 The dissection may affect the entire circumference of
the aortic media or a segment of it.
 In about 10% of dissecting aneurysms,a second intimal
tear is seen in the distal part of the dissection so that the
blood enters the false lumen through the proximal tear
and re-enters the true lumen through the distal tear.
 If the patient survives, the false lumen may develop
endothelial lining and ‘double-barrel aorta’ is formed.

9. Thoracic aorta and intramural haematoma have been described
 I. DeBakey classification. Depending upon the extent of aortic
dissection, three types are described:
 Type I: Comprises 75% of cases; the intimal tear begins in the
ascending aorta but dissection extends distally for some distance.
 Type II: Comprises 5% of cases and dissection is limited to the
ascending aorta.
 Type III: Constitutes the remaining 20% cases. In these cases, intimal
tear begins in the descending thoracic aorta near the origin of
subclavian artery and dissection extends distally.

10.  II. Stanford classification. Depending upon clinical
 management, these are divided into 2 types:
 Type A (Proximal dissection): Involves the
ascending aorta
 and includes type I and II of the above scheme
because clinical management of DeBakey type I
and II is not
 different.
 Type B (Distal dissection): Limited to descending
aorta and
 sparing the ascending aorta; it corresponds to
DeBakey type III

13.  EFFECTSThe classical clinical manifestation of a dissecting aneurysm is
excruciating tearing pain in the chest moving downwards.
 The complications arising from dissecting aneurysms are as under:
 1. Rupture Haemorrhage from rupture of a dissecting
 aneurysm in the ascending aorta results in mortality in 90% of cases. Most
often, haemorrhage occurs into the pericardium;
 less frequently it may rupture into thoracic cavity, abdominal cavity or
retroperitoneum.
 2. Cardiac disease –
 Involvement of the aortic valve results in aortic incompetence. Obstruction
of coronaries results in ischaemia causing fatal myocardial infarction.
 Rarely, dissecting aneurysm may extend into the cardiac chamber.
 3. Ischaemia –
 Obstruction of the branches of aorta by dissection results in ischaemia of
the tissue supplied.
 Thus,there may be renal infarction, cerebral ischaemia and infarction of the
spinal cord.

15.  Abdominal ultrasound.This test is most commonly used to
diagnose abdominal aortic aneurysms.You lie on a table while a
technician moves a wand (transducer) around your abdomen.
Ultrasound uses sound waves to send images to a computer
screen.
 CT scan.This painless test can provide your doctor with clear
images of your aorta, and it can detect the size and shape of an
aneurysm.
 During a CT scan, you lie on a table inside a doughnut-shaped
machine. CT scanning generates X-rays to produce cross-sectional
images of your body.You might have contrast dye injected into
your blood vessels that makes your arteries more visible on the CT
pictures (CT angiography).
 MRI. In this test, you lie on a movable table that slides into a
machine. An MRI uses a magnetic field and pulses of radio wave
energy to make pictures of your body.You might have a dye
injected into your blood vessels to make them more visible
(magnetic resonance angiography).

16.  Being male and smoking
significantly increase the risk
of abdominal aortic aneurysm.
Screening recommendations
vary, but in general:
 Men ages 65 to 75 who have
ever smoked cigarettes should
have a one-time screening
using abdominal ultrasound.
 For men ages 65 to 75 who
have never smoked, your
doctor will decide on the need
for an abdominal ultrasound,
usually based on other risk
factors, such as a family
history of aneurysm.

17.  SURGERY
 Open abdominal surgery.This involves removing the damaged section of
the aorta and replacing it with a synthetic tube (graft), which is sewn into
place. Full recovery is likely to take a month or more.
 Endovascular repair.This less invasive procedure is used more often.
Doctors attach a synthetic graft to the end of a thin tube (catheter) that's
inserted through an artery in your leg and threaded into your aorta.
 The graft — a woven tube covered by a metal mesh support — is placed at
the site of the aneurysm, expanded and fastened in place. It reinforces the
weakened section of the aorta to prevent rupture of the aneurysm.
 Endovascular surgery isn't an option for about 30 percent of people with
an aneurysm. After endovascular surgery, you'll need regular imaging tests
to ensure that the repair isn't leaking.
 Long-term survival rates are similar for both endovascular surgery and
open surgery.

19.  Don't use tobacco products.Quit smoking or chewing
tobacco and avoid secondhand smoke.
 Eat a healthy diet. Focus on eating a variety of fruits and
vegetables, whole grains, poultry, fish and low-fat dairy
products. Avoid saturated fat, trans fats and limit salt.
 Keep your blood pressure and cholesterol under control. If
your doctor has prescribed medications, take them as
instructed.
 Get regular exercise.Try to get at least 150 minutes a week
of moderate aerobic activity. If you haven't been active, start
slowly and build up.Talk to your doctor about what kinds of
activities are right for you.
 If you're at risk of an aortic aneurysm, your doctor might
recommend other measures, such as medications to lower
your blood pressure and relieve stress on weakened arteries.

20.  Goldschmidt-Clermont PJ et al: Atherosclerosis 2005: Recent discoveries
 and novel hypotheses. Circulation 112:3348, 2005.
 Grundy SM,Theroux P: Pathophysiology of coronary artery disease.
 Circulation 111:3481, 2005.
 Dalman RL, et al. Overview of abdominal aortic aneurysm.
https://www.uptodate.com/contents/search. Accessed Jan. 21, 2019.
 Spryngerd M, et al. Screening program of abdominal aortic aneurysm. Angiology.
Jan. 17, 2019; e1. https://doi.org/10.11770003319718824940. Accessed Jan. 21,
2019.
 Abdominal aortic aneurysms (AAA). Merck Manual ProfessionalVersion.
http://www.merckmanuals.com/professional/cardiovascular-disorders/diseases-
of-the-aorta-and-its-branches/abdominal-aortic-aneurysms-aaa. Accessed Jan.
21, 2019.
 Final recommendation statement abdominal aortic aneurysm: Screening. U.S.
Preventive ServicesTask Force.
https://www.uspreventiveservicestaskforce.org/Page/Document/Recommendati
onStatementFinal/abdominal-aortic-aneurysm-screening. Accessed Feb. 5, 2019.
 Riggin ER.Allscripts EPSi. Mayo Clinic, Rochester, Minn. March 6, 2019.
 Connolly HM (expert opinion). Mayo Clinic, Rochester, Minn. March 11, 2019