Aneurysm. It is a blood sac that communicates with the lumen of an artery They are classified...
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Transcript of Aneurysm. It is a blood sac that communicates with the lumen of an artery They are classified...
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