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
Incidence of Abdominal Aortic Aneurysm
- The most frequent type of aneurysms.
* It affects the aorta below the origin of the renal arteries in 95% of cases
ETIOLOGY of Abdominal Aortic Aneurysm
Atherosclerosis is most common cause
and is responsible for 95% of AAAs.
Clinical picture of AAA
- Asymptomatic aneurysms
- Pain is the commonest symptom :
- Swelling “Not Common”:
Asymptomatic aneurysms in Clinical picture of AAA
In 75% of patients the AAA is discovered accidentally during a routine abdominal U.S examination.
Pain in Clinical picture of AAA
- Incidence
* Pathogenesis
Incidence of Pain in Clinical picture of AAA
The commonest symptom
Pathogenesis of Pain in Clinical picture of AAA
- An A.A.A. gradually enlarges and compresses on surrounding structures causing vague abdominal pain & dyspepsia.
- Back and flank pain result from vertebral compression.
Swelling in Clinical picture of AAA
- Incidence
* Pathogenesis
Incidence of Swelling in Clinical picture of AAA
Not common
Pathogenesis of Swelling in Clinical picture of AAA
- Visible pulsating abdominal mass
* in cases of large AAA reaching the anterior abdominal wall.
Complications of AAA
- Rupture “The most serious complication”
2. Distal embolization
Rupture in Complications of AAA
- The classic triad
* Types of rupture
The classic triad of Rupture in Complications of AAA
- Sudden severe pain
- Pulsatile abdominal mass.
- Shock
Types of rupture of Rupture in Complications of AAA
Retroperitoneal rupture: Can be saved
Intraperitoneal rupture is fatal & the patient usually does not reach the hospital.
Alternative name for Retroperitoneal rupture in Types of rupture of Rupture in Complications of AAA
Postero-lateral rupture
Alternative name for Intraperitoneal rupture in Types of rupture of Rupture in Complications of AAA
Anterior rupture
Distal embolization in Complications of AAA
- Definition
* Consequences
Definition of Distal embolization in Complications of AAA
A mural thrombus within the aneurysm may be the source for athero-embolization
Consequences of Distal embolization in Complications of AAA
a) Acute embolic ischemia
b) Blue toe syndrome
Acute embolic ischemia in Consequences of Distal embolization in Complications of AAA
if the embolus is lodged in a large artery
Blue toe syndrome in Consequences of Distal embolization in Complications of AAA
- if a small embolus is lodged in one of the digital arteries of the toes.
- The toes are cold blue & ischemic while the patient is having intact pedal pulse.
Investigation of AAA
- Abdominal U.S “Best screening test”.
- CT scan :
- Angiography or digital subtraction angiography :
Best screening test for AAA
Abdominal U.S
Advantages of CT scan in Investigation of AAA
- very accurate in determining the size of the aneurysm
* very accurate in the diagnosis of leaking or ruptured AAA
Angiography or digital subtraction angiography in the investigation of AAA
- Advantages
* Disadvantages
Advantages of Angiography or digital subtraction angiography in the investigation of AAA
lt allows identification of iliac artery involvement as well as suprarenal extension
lt provides precise assessment of associated occlusive disease of the peripheral arteries as well as the renal and mesenteric arteries.
Disadvantages of Angiography or digital subtraction angiography in the investigation of AAA
Angiography or digital subtraction angiography is Not reliable to determine the diameter of the aneurysm
the reason why Angiography or digital subtraction angiography is Not reliable to determine the diameter of the aneurysm
because of the mural thrombus which reduces the aneurysm lumen size.
Treatment of AAA
- Plan of management
* Type of surgery for aneurysm repair
Plan of management in Treatment of AAA
- Immediate surgery
- Urgent surgery
- Elective surgery
- Regular follow up
Indication of Immediate surgery in Plan of management in Treatment of AAA
patients with the diagnosis of rupture
Indication of Urgent surgery in Plan of management in Treatment of AAA
- patients with symptoms of acute expansion
symptoms of acute expansion in Indication of Urgent surgery in Plan of management in Treatment of AAA
severe pain of acute onset but with no leak on C.T. scan
Indication of Elective surgery in Plan of management in Treatment of AAA
a) Symptomatic aneurysms regardless of the size
b) Asymptomatic aneurysms 5 cm or more in diameter
Regular follow up in Plan of management in Treatment of AAA
- Indication
- Modalities
- Time of intervention
Indication of Regular follow up in Plan of management in Treatment of AAA
Asymptomatic aneurysms less than 5 cm in diameter
Modalities of Regular follow up in Plan of management in Treatment of AAA
Ultrasound is done every 6 months.
Time of intervention in Regular follow up in Plan of management in Treatment of AAA
- Surgery is required if the serial studies show an enlarging aneurysm > 5 mm in 6 months
or
- The patient becomes symptomatic
Type of surgery for aneurysm repair in Treatment of AAA
A. Open exclusion graft
B. Endovascular repair
Open exclusion graft in Type of surgery for aneurysm repair in Treatment of AAA
- Principle
* Complications
Principle of Open exclusion graft in Type of surgery for aneurysm repair in Treatment of AAA
- Opening the aneurysm and excluding it by implanting a synthetic graft
- The anterior wall of the aneurysm should be closed over the synthetic graft
The reason why The anterior wall of the aneurysm should be closed over the synthetic graft in Principle of Open exclusion graft in Type of surgery for aneurysm repair in Treatment of AAA
- To separate it from the bowel
* To avoid pressure necrosis And aortoenteric fistula
Complications of Open exclusion graft in Type of surgery for aneurysm repair in Treatment of AAA
تنطيط
- Declamping hypotension
- Trash foot
- Left colon ischemia
- Paraplegia
- Renal failure.
Declamping hypotension in Complications of Open exclusion graft in Type of surgery for aneurysm repair in Treatment of AAA
Due to accumulation of V.D metabolites in ischaemic limbs
Trash foot in Complications of Open exclusion graft in Type of surgery for aneurysm repair in Treatment of AAA
- Microembolization to the digital arteries of the feet
* occurs with aortic aneurysm repair
Left colon ischemia in Complications of Open exclusion graft in Type of surgery for aneurysm repair in Treatment of AAA
due to Affection of inferior mesenteric arteries
Paraplegia in Complications of Open exclusion graft in Type of surgery for aneurysm repair in Treatment of AAA
due to Affection of Lumbar arteries
Endovascular repair in Type of surgery for aneurysm repair in Treatment of AAA
Principle:
Indications
Principle of Endovascular repair in Type of surgery for aneurysm repair in Treatment of AAA
insertion of an endoluminal stented graft through bilateral femoral arteriotomies.
Indications of Endovascular repair in Type of surgery for aneurysm repair in Treatment of AAA
This technique is expensive & recurrence of the aneurysm may occur.
It is therefore indicated for :
* High risk patients who can not tolerate anesthesia and open surgery
Pathogenesis of recurrence in Indications of Endovascular repair in Type of surgery for aneurysm repair in Treatment of AAA
failure of Fixation of graft
Incidence of Popliteal aneurysm
the commonest peripheral aneurysm.
Etiology of Popliteal aneurysm
1) Traumatic
2) Pathological
Morphology of Traumatic Etiology of Popliteal aneurysm
Saccular
Main complication of Traumatic Etiology of Popliteal aneurysm
rupture
Morphology of Pathological Etiology of Popliteal aneurysm
Fusiform
Main complication of Pathological Etiology of Popliteal aneurysm
- Thrombosis and
* Distal embolization
Clinical picture of Popliteal aneurysm
Usually small size swelling (3-4 cm)
but ischaemia is common.
Treatment of Popliteal aneurysm
Exclusion & bypass using autogenous saphenous vein graft
No attempt to excise the aneurysm as damage to the popliteal vein will occur.
problem about Treatment of Popliteal aneurysm
No attempt to excise the aneurysm as damage to the popliteal vein will occur.
Cause of pseudo aneurysm
Penetrating trauma
Treatment of pseudo aneurysm
- Evacuation (not excision)
* Arterial repair by suture or vein patch graft
Recent trends in management of pseudo-aneurysm
- U.S guided compression.
- U.S guided thrombin injection.
- Embolization.
- Endovascular stent graft