Arterial.9.Aneurysm Flashcards
Definition of aneurysm
It’s a sac that contains blood and communicates with the lumen of an artery
Classification of aneurysm
Aneurysms can be classified according to
- Etiology :
- Structure : True or false.
- Shape : Fusiform, saccular
Etiology in Classification of aneurysm
- Pathological
- Traumatic
- Congenital
Pathological Etiology in Classification of aneurysm
1) Atherosclerosis.
2) Collagen diseases :
3) Syphilis.
Collagen diseases in Pathological Etiology in Classification of aneurysm
- Behcet’s disease.
- Marfan syndrome
- Ehler’s Danlos syndrome.
Traumatic Etiology in Classification of aneurysm
A. Blunt trauma:
B. Penetrating injury
Pathogenesis of Blunt trauma in Traumatic Etiology in Classification of aneurysm
- Blunt trauma to an artery may weaken part of its wall.
* Later this weak area progressively yields leading to aneurysmal dilatation.( True aneurysm)
Pathogenesis of Penetrating trauma in Traumatic Etiology in Classification of aneurysm
- A penetrating injury to an artery may cause a small hole in the wall Leading to a haematoma surrounding the artery.
- Later on, this clot is surrounded by a false capsule of organised fibrous tissue and the result will be a false aneurysm
Congenital Etiology in Classification of aneurysm
- These may occur in the circle of Willis & causes subarachnoid haemorrhage.
- Other sites include the splenic, renal or coeliac vessels.
Structure in Classification of aneurysm
True aneurysms
False aneurysms
True aneurysms in Structure in Classification of aneurysm
The wall of a true aneurysm is formed of the 3 layers of the dilated artery.
False aneurysms in Structure in Classification of aneurysm
- a false aneurysm is actually a haematoma communicating with lumen of an artery through a partial tear in its wall.
- Thus, the wall of the false aneurysm is formed by the fibrous wall of the haematoma
Clinical picture of aneurysms
- Symptoms
* Examination
Symptoms in Clinical picture of aneurysms
- Silent aneurysms :
- Swelling
- Symptoms of complications or compression on adjacent structures.
Silent aneurysms in Symptoms in Clinical picture of aneurysms
Some aneurysms e.g. of the abdominal aorta are commonly silent & accidentally discovered on ultrasound examination that is done for another reason.
Examination in Clinical picture of aneurysms
- Site
- shape
- Surface
- Consistency
- Compressibility
- Special character
- Special tests
- Palpation and Auscultation
Site in Examination in Clinical picture of aneurysms
swelling lies along the line of an artery.
shape in Examination in Clinical picture of aneurysms
rounded swelling
Surface in Examination in Clinical picture of aneurysms
Smooth swelling
Consistency in Examination in Clinical picture of aneurysms
cystic swelling
Compressibility in Examination in Clinical picture of aneurysms
Compressible swelling
Special character in Examination in Clinical picture of aneurysms
- The swelling gives expansile pulsations
* The most important sign
Special tests in Examination in Clinical picture of aneurysms
Proximal pressure on the main artery results in diminution or disappearance of pulsations
Distal compression on the main artery causes the aneurysm to increase in size and become more tense
Palpation and Auscultation in Examination in Clinical picture of aneurysms
A systolic thrill may be felt
A bruit may be heard
most important sign of aneurysm in Examination in Clinical picture of aneurysms
The swelling gives expansile pulsations
meaning of expansile pulsations
pulsations in all directions
Complications of aneurysm
- Rupture
- Distal ischaemia :
- Infection
- Compression on adjacent structures
Rupture in Complications of aneurysm
- the most serious complication )> fatal hge
* Pseudo aneurysm is more liable to rupture (its wall is fibrous tissue)
The most serious complication of aneurysm
Rupture
Etiology of distal ischemia in Complications of aneurysm
a) Acute ischaemia
b) Chronic ischaemia
Pathogenesis of Acute ischaemia in Etiology of distal ischemia in Complications of aneurysm
a mural thrombus within the aneurysm may be the source for athero-embolization.
Pathogenesis of Chronic ischaemia in Etiology of distal ischemia in Complications of aneurysm
gradual decrease of blood supply distal to the aneurysm.
Infection in Complications of aneurysm
Leads to :
- Rupture
- Secondary haemorrhage
Compression on adjacent structures in Complications of aneurysm
- Compression of an adjacent vein may cause DVT.
- Compression of a nerve may cause motor or sensory affection.
- The adjacent bone may also be eroded.
Differential Diagnosis of aneurysms
- An arterio-venous fistula “Varicose aneurysm”.
- A swelling overlying an artery may elicit transmitted arterial pulsations :
- A very vascular tumour as an osteosarcoma or metastases.
- An abscess.
difference between aneurysms and a swelling overlying an artery
- Pressure on the proximal artery
* Moving the swelling away from the artery
Pressure on the proximal artery in aneurysms in difference between aneurysms and a swelling overlying an artery
Decrease its size
Pressure on the proximal artery in a swelling overlying an artery in difference between aneurysms and a swelling overlying an artery
does not change the size of the swelling.
Moving the swelling away from the artery in aneurysms in difference between aneurysms and a swelling overlying an artery
The pulsations Persists
Moving the swelling away from the artery in a swelling overlying an artery in difference between aneurysms and a swelling overlying an artery
The pulsations disappear
Treatment of aneurysms
- The standard line of treatment is excision and graft.
- Exclusion graft
- Excision with arterial ligation
Indication of Excision with arterial ligation
can be done for aneurysms of small arteries as the radial and ulnar arteries