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 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 affection 3.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

Investigations Plain 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 foot 5.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 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

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