Aneurysm
Aneurysm It is a blood sac that communicates with the lumen of an artery They are classified according to Etiology congenital Acquired pathological , traumatic and
Aneurysm They are classified according to Structure Shape true or false Shape fusiform saccular dissecting
Aneurysm
Aneurysm (Etiology) Congenital Acquired –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 ) On the line of an artery Expansile pulsation Decrease with proximal compression Increase with distal compression A murmur or bruit Weak distal pulses
Aneurysm (Clinical) C-Secondary effects D- Complications Adjacent structures compression Vein ~thrombosis Nerve~sensory or motor affection Bone ~ erosion Ischemic limb Embolism & thrombosis D- Complications Rupture Thrombosis ~ to acute ischemia Distal emboli~ distal ischemia Infection ~secondary hemorrhage due to rupture
Differential diagnosis Very vascular tumors Pulsating hematoma Abscess A swelling overlying an artery A swelling under an artery AV fistula Turtous artery ( Circoid aneurysm) Pulsating empyema encephalocele
Investigations Doppler U/S Plain X ray ( calcification) Spiral CT scan Arteriography
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 ? Probably males over 65 years - especially hypertensives Single U/S at 65 years reduces death from ruptured AAA by 70% in screened population Patients with small aneurysms should undergo regular surveillance Repeated ultrasound every 6 months
Clinical features 75% are a-symptomatic Possible symptoms include Epigastric pain Back pain Malaise and weight loss (with inflammatory aneurysms) Multiple small infarction in the on the foot DIC
Clinical features Rupture presents with Rare presentations include 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 investigation Need 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