Aneurysm

AneurysmIt is a blood sac that

communicates with the lumen of an artery

They are classified according to – Etiology

• congenital• Acquired

– pathological ,

– traumatic and

AneurysmThey are classified

according to

Structure true or

false

Shape • fusiform • saccular • dissecting

Aneurysm

Aneurysm (Etiology)Congenital

–Cerebral , splenic , renal or celiac

Acquired– Degenerative Atherosclerosis (Commonest)– Traumatic

• Blunt trauma that weakens an area of the wall• Penetrating trauma causing false aneurysm (pulsating hematoma)

– Post stenotic– Cystic medial necrosis – Septic emboli of subacute endocarditis – Marfan’s syndrome – Ehler Danlos syndrome– Syphilis

Aneurysm (Clinical)

A- Silent

B- The presence of a swelling (6 criteria )

1.On the line of an artery

2.Expansile pulsation

3.Decrease with proximal compression

4.Increase with distal compression

5.A murmur or bruit

6.Weak distal pulses

Aneurysm (Clinical)

C-Secondary effects– Adjacent structures compression

1. Vein ~thrombosis 2. Nerve~sensory or motor affection3. Bone ~ erosion

• Ischemic limb• Embolism & thrombosis

D- Complications 1. Rupture 2. Thrombosis ~ to acute ischemia 3. Distal emboli~ distal ischemia 4. Infection ~secondary hemorrhage due to rupture

Differential diagnosis

1. Very vascular tumors

2. Pulsating hematoma

3. Abscess

4. A swelling overlying an artery

5. A swelling under an artery

6. AV fistula

7. Turtous artery ( Circoid aneurysm)

8. Pulsating empyema

9. encephalocele

InvestigationsPlain X ray ( calcification) Doppler U/S

•ArteriographySpiral CT scan

Treatment

Surgery is indicated if the size is more than 4 cm(range up to 7 cm )

• Standard treatment is – excision with graft replacement – Insertion of the graft can be done inside the sac

without its removal

• Excision with arterial ligation in aneursyms of small arteries

• Procedures not in use– Endo-aneurysmorraphy– Endoluminal thrombosis

Abdominal aortic aneurysms

• An AAA is an increase in aortic diameter by greater than 50% of normal

• Usually regarded as aortic diameter of greater than 3 cm diameter

• More prevalent in elderly men

• Male : female ratio is 4:1

Abdominal aortic aneurysms

AAA diameter expands exponentially at  approximately 10% / year ( 3mm Year)

Risk of rupture increases as aneurysm expands (Laplace law)

5 year risk of rupture: o        5.0 – 5.9 cm = 25% o        6.0 – 6.9 cm = 35% o        More than 7 cm = 75%

Overall only 15% aneurysms ever rupture 85% of patients with a AAA die from an unrelated

cause

Screening• AAA are suitable for screening as

elective operation of asymptomatic aneurysms can reduce mortality associated with rupture

– Mortality of emergency operation is > 50%

– Mortality of elective surgery is < 5%

Screening– Who should be screened ?

1. Probably males over 65 years - especially hypertensives

2. Single U/S at 65 years reduces death from ruptured AAA by 70% in screened population

3. Patients with small aneurysms should undergo regular surveillance

4. Repeated ultrasound every 6 months

Clinical features

75% are a-symptomatic Possible symptoms include

1. Epigastric pain 2. Back pain 3. Malaise and weight loss (with

inflammatory aneurysms)4. Multiple small infarction in the on the foot5. DIC

Clinical features

• Rupture presents with o        Sudden onset abdominal pain

o        Hypovolaemic shock

o        Pulsatile epigastric mass

• Rare presentations include o        Distal embolic features

o        Aorto-caval fistula

o        Primary aorto-intestinal fistula

Pre-operative investigationNeed to determine

– Extent of aneurysm – Fitness for operation

Methods– Ultrasound, – Conventional CT and– More recently spiral CT

Determines – Aneurysm size, – Relation to renal arteries, – Involvement of iliac vessels

Pre-operative investigation

Most significant post operative morbidity and mortality related to cardiac disease

so if there is pre-operative symptoms of cardiac disease patient will need

– cardiological opinion

– May need thallium scan or

– cardiac catheterisation

– Cardiac revascularisation required in up to 10% patients

Surgery

Surgery

Surgery

Surgery

Surgery

Endo-vascular repair

• Introduced by Parodi 1991

• There is a few clinical trials over the past 10 years .

• the complications of the technique is not yet finally determined.

Endo-vascular repair

• It is done to avoid complications of open surgery which is mainly related to cross clamping of the aorta especially if it is above the renal arteries – spinal cord ischemia ,– renal ischemia

Endo-vascular repair