Arterial Aneurysms

Question 1

What is an aneurysm?

Answer 1

A focal permanent dilatation of an artery that is > 1,5 times the normal diameter of the artery

Question 2

What is ectasia?

Answer 2

Focal dilatation of an artery that is <1,5 the normal diameter but >1 x the diameter

Question 3

What is arteriomegaly?

Answer 3

Diffuse dilatation of the entire arterial segment

Question 4

What is aneurysmosis?

Answer 4

Multiple arterial aneurysms with intervening normal arterial segments

Question 5

5 complications of arterial aneurysms

Answer 5

Rupture 
Acute or chronic thrombotic occlusion 
Acute or recurrent thromboembolism 
Pressure related complications 
Spontaneous fistulisation

Question 6

what is a true aneurysm

Answer 6

The wall of the aneurysm (sac) incorporates all the conventional layers of an artery, i.e. the intima, media and adventitia.

Question 7

what is a false aneurysm?

Answer 7

The wall of the aneurysm comprises adventitia and compressed surrounding tissue only.

Question 8

what is the aetiology of arterial aneurysms

Answer 8

• degenerative aneurysms
• infective aneurysms
• connective tissue disorders
• trauma

Question 9

how are arterial aneurysms classified?

Answer 9

Anatomical location
· Aneurysm type: True or false
(pseudoaneurysms)
· Morphology
· Size
· Aetiology
· Clinical presentation

Question 10

explain the classification of arterial aneurysms based on anatomical location

Answer 10

aortic - abdominal aortic aneurysm, thoraco abdominal aortic aneurysm
non aortic - peripheral, renal,carotid, subclavian

Question 11

explain the classification of arterial aneurysms based on morphology

Answer 11

fusiform - spindle shaped

saccular - saccular outpouching in an arterial segment ( complicated at a smaller diameter compared to fusiform )

Question 12

explain the classification of arterial aneurysms based on size and the consequence for treatment

Answer 12

small: asymptomatic, low risk of complications - observe over time
large: even if asymptomatic have a high risk of complication therefore treat early

Question 13

explain the classification of arterial aneurysms based on aetiology

Answer 13

degenerative: atherosclerotic, fibromuscular dysplasia, intimo medial mucoid degeneration
infective: tb, syphyllis
inflammatory/vascultis: takayasus, giant cell arteritis
connective tissue: marfans, ehler danlos
post dissection: cystic media necrosis, trauma
post stenotic: thoracic outlet syndrome, coarctation of the aorta
trauma:
congenital: turners, menkes syndrome, tuberous sclerosis

Question 14

what is the most common aneurysm

Answer 14

abdominal aortic aneurysm AAA

Question 15

how are AAAs classified anatomically?

Answer 15

• Infra-renal: ~ 90% of AAAs are infra-renal
  · Juxta-renal: the proximal neck (distance between the renal arteries and the aneurysm sac) is less than 8mm in length.
  · Para-renal: one of the renal arteries comes off the aneurysm itself
  · Supra-renal: both the renal arteries and or the mesenteric vessels come off the aneurysm
  · Thoraco-abdominal aortic aneurysm (TAAA): This may involve any part of the aorta between the left subclavian artery and the aortic bifurcation. Some of these TAAAS have a AAA component as well.

Question 16

why do AAAs develop? list 5 theories?

Answer 16

Uncontrolled hypertension
· Hypercholesterolaemia
· Smoking
· Imbalances between proteases
and anti-proteases[ --> destruction of collagen and elastin in the media. These enzymes include elastase and metallo-proteinase (MMP) 2 and 9]
· Infection: chlamydia pneumonia

Question 17

classify AAAs accordign to size

Answer 17

small: 4-5.5cm and low risk of rupture 1-2%
large: >5.5cm in diameter with high risk of rupture

Question 18

Relate aneurysm size and risk of rupture

Answer 18

<4cm     0% per year
4-5cm    0.5 to 5% per year
5-6cm   3 to 15% per year
7-8cm    10 to 20% per year
7-8cm     20 to 40% per year 
>8cm    30 to 50% per year

Question 19

clinical approach to aneurysms

Answer 19

asymptomatic
symptomatic
complicated

Question 20

typical symptoms in patients with AAA

Answer 20

Vague abdominal pain
· Recent onset backache
· Vomiting (duodenal
compression)
· Constipation (colonic
compression)
· Flank pain (ureteric
compression)
· Chronic venous disease
(venous compression)

Question 21

complications of AAA

Answer 21

acute lower limb ischaemia (macro embolism)
blue toe syndrome ( microembolism)
rupture: free intraperitoneal or contained retroperitoneal or chronic contained leak
aorto enteric fistula
aorta caval fistula

Question 22

which imaging modalities are used to confrim the diagnosis fo AAA

Answer 22

abdominal duplex ultrasound (DUS)
computed tomography angiography CTA
magnetic resonance angiography
conventional digital subtraction angiography

Question 23

why should we screen for AAA?

Answer 23

70% are asymptomatic (undetected) prior to rupture.
overall mortality for ruptured AAA = 90%
~75% die before reaching a hospital.

< 5% mortality with elective AAA repairs.

Ultrasound is effective and inexpensive.

MASS trial: ~53% reduction in aneurysm related mortality

Question 24

who do we screen for AAA?

Answer 24

Elderly Caucasian males > 65 years
· Elderly patients with documented peripheral aneurysms
· Patients with documented thoracic aortic aneurysms
· Family history of AAAs

Question 25

how do we conservatively treat AAA?

Answer 25

``` Smoking cessation strategies · Weight loss · Anti-platelet therapy · Lipid-lowering strategies · B-Blockers · Optimum blood pressure control ```

Question 26

indications for surgical intervention

Answer 26

``` -All symptomatic AAAs · All complicated AAAs · Asymptomatic AAA > 5.5 cm in males · Asymptomatic AAAs > 5 cm in females · Small AAAs on surveillence with rapid enlargement ( > 1 cm after 1 year on repeat scan) · Asymptomatic AAA with a large iliac aneurysm > 3cm · Asymptomatic saccular AAA >3 cm ```

Question 27

surgical options

Answer 27

open repair EVAR laparoscopic assisted AAA repair +robotic assisted AAA repairs

Question 28

risk factors for operative mortality

Answer 28

Age > 70 years Gender – females Renal dysfunction / chronic renal failure Severe pulmonary dysfunction Cardiac co-morbidity: recent myocardial infarction, intractable CCF,unstable angina, significant arrhythmia or valvular disease.

Question 29

what is the classic triad that pts present with after a ruptured AAA

Answer 29

-Sudden onset severe backache · Shock · Pulsatile abdominal mass

Question 30

what is cullens sign?

Answer 30

bluish discolouration involving the scrotum, around the umbilicus

Question 31

what is grey turners sign?

Answer 31

blue ish discolouration involving the flanks

Question 32

on admission pts should be evaluated with these investigations

Answer 32

``` A full blood count · Creatinine levels · Electrocardiogram (ECG) · Serial blood pressure recordings · The patients age · The patients co-morbidities · History of previous abdominal /vascular surgery ```

Question 33

what are the 5 variables in the hardman risk index and what is it for?

Answer 33

It is a predictive scoring system that aids decision making for intervention 1. Age > 79 (octogenerians or older) ·2 Blood pressure persistently < 90 mmHg systolic · 3Creatinine > 179 uMol/L · 4 Haemoglobin level < 9 g/dL · 5 Ischaemic ECG

Question 34

how does one interpret the hardman risk index score?

Answer 34

3 or more variables: 100% operative mortality 2 variables: 70% mortality - can be offered surgery 1 or less variables" benefit enormously from surgery 0 variables: operative mortality still 15%

Question 35

where are thoraco abdominal aortic aneurysms located

Answer 35

distal to the left subclavian artery and involves both the descending thoracic and abdominal aorta

Question 36

aetiology of TAAAs 6 examples

Answer 36

``` - Non-specific degenerative · Takayasu’s disease · Intimo-medial mucoid degeneration · HIV-related aneurysms · Mycotic aneurysms · Tuberculous aortitis with aneurysms ```

Question 37

clinical features of TAAA

Answer 37

``` -High interscapular backache · Chest and/or abdominal pains · Dysphagia · Dysnoea · Stridor, hoarseness, superior vena cava syndrome (these are more common in aortic arch aneurysms) ```

Question 38

treatment options for TAAA

Answer 38

1. open surgical repair 2. hybrid procedures 3. endovascular repair

Question 39

explain how a dissecting aortic aneurysm develops

Answer 39

complication of chronic aortic dissection --> arterial wall dissects via an intimal tear resulting in a true lumen and a false lumen --> the false lumen gradually enlarges to become aneurysmal

Question 40

what is the difference between stanford A and stanford B acute aortic aneurysms?

Answer 40

stanford A: arising from ascending aorta and treated surgically stanford B: arising from distal to the left subclavian artery and mostly managed medically B more common than A

Question 41

clinical features of dissecting aortic aneurysms

Answer 41

Features of compression (chest pain, dysnoea, dysphagia, etc) · Rupture (overall mortality > 95%) · Malperfusion. The dissection may extend into aortic branch vessels resulting in ischaemic complications viz. stroke, mesenteric ischaemia, renal dysfunction, lower extremity ischaemia, paraplegia.

Question 42

treatment options for dissecting aortic aneurysms

Answer 42

1. Open surgical repair 2. Endovascular thoracic aneurysm repair (TEVAR) 3. Hybrid procedures

Question 43

clinical features of peripheral aneurysms ( lower extremity > upper extremity)

Answer 43

1. Thrombo-embolic complications · Acute limb ischaemia · Claudication · Critical limb ischaemia · Blue toe syndrome / Blue digit syndrome 2. Features of compression · Regional / discomfort · Limb swelling /distended veins(venous compression) · Nerve compression 3. Rupture. This is exceptionally rare in peripheral aneurysms (< 5%)

Question 44

clinical presentation of popliteal aneurysms

Answer 44

Approximately 50% are bilateral · Approximately 50% have an associated AAA · Approximately 40% – 50% will have an associated femoral aneurysm · Approximately 50% will present clinically with acute limb ischaemia

Question 45

2 most common peripheral aneurysms

Answer 45

popliteal and femoral account for 90% of peripheral aneurysms

Question 46

aetiology of popliteal aneurysms

Answer 46

non specific degenerative trauma HIV related tuberculous aneurysm

Question 47

indications for treatment of popliteal aneurysm

Answer 47

· All symtomatic or complicated aneurysms | · All asymptomatic non-specific degenerative aneurysms > 2cm

Question 48

treatment of popliteal aneurysm

Answer 48

1. Open surgical repair. 2. Endovascular popliteal aneurysm repair (EVPAR) using peripheral covered stents.

Question 49

complications of popliteal aneurysms

Answer 49

thrombotic occlusion thromboembolism rupture

Question 50

aetiology of femoral aneurysms

Answer 50

``` · Pseudoaneurysms. These are anastomotic aneurysms = =most common femoral aneurysms. · Non-specific degenerative aneurysms · HIV-related aneurysms · Tuberculous aneurysms · Mycotic aneurysms · Trauma ```

Question 51

clinical presentation of femoral aneurysms

Answer 51

· Approximately 70% are bilateral | · Approximately 25% are associated with a AAA

Question 52

indications for treatment of femoral aneurysms

Answer 52

· All symptomatic or complicated femoral aneurysms | · All asymptomatic non-specific degenerative aneurysms > 2.5 cm

Question 53

treatment of femoral aneurysms

Answer 53

open surgical repair