Definitions

Congenital or acquired localised area of

abnormal dilations of blood vessels or the

heart

Whats the importance?

Aneurysm & dissections are important causes of

stasis & subsequent thrombosis, tendency to rupture.

Types of Aneurysm

True aneurysm

- Involves all 3 layers of

the artery

(intima, media, adventitia)

- attenuated wall of the heart

- Eg: atherosclerotic, congenital

aneurysms, syphilitic aneurysm,

ventricular aneurysm from

transmural MI

False Aneurysm

- wall defect that leads to

extravascular hematoma that

communicate with the

intravascular space

(pulsating hematoma)

- Eg: ventricular rupture after MI

contained by pericardial adhesions

& leaks at the junction of a

vascular graft with a natural artery

Spherical outpouching 5cm 20cm Often contain thrombus

Cylindrical dilation

Causes of Aneurysms

1) Loss of smooth muscles cells or change in the smooth muscle cell

synthetic phenotype (ischemia, Marfan syndrome)

Most commonly:

Atherosclerosis (Abdominal aortic aneurysm) and hypertension

(Ascending aortic aneurysm)

2) Excessive connective tissue degradation

(eg. Local inflammatory response Macrophages in atherosclerotic

plaque, MMP, TIMP cystic medial degeneration)

3) Weakened vessel walls (trauma, vasculitis, congenital defects berry

aneurysm, infections mycotic aneurysms, 3syphilis- obliterative

endarteritis esp ascending thoracic aorta)

4) Inadequate or abnormal connective tissue synthesis (eg. Marfan

syndrome-defective synthesis of fibrillin, Ehlers-Danlos syndrome-deficient

synthesis of type III collagen for bv, bowel wall)

Example of Aneurysms Berry aneurysm - replacement of muscular wall by fibrous tissue,

involve Circle of Willis at the point of branching, young to middle age (suspect when young pt have chronic headache)

Predisposing factor : Hypertension

Complication : Subarachnoid hemorrhage

Capillary microaneurysm (Charcoat-Bouchard) - rupture of branches of arteris in brain (eg: middle cerebral artery)

- adult, HPT due to hyaline arteriolosclerosis, cn cause stroke

Syphilitic aneurysm - 3 syphilis, ascending thoracic & arch of aorta

Mycotic aneurysm - Bacterial or fungal infection via blood streeam

- Involve cerebral vessels

Abdominal Aortic Aneurysm

Anteropostero diameter of 3cm is generally accepted as aneurysm

Degeneration of the elastin and collagen

(Local inflammatory infiltrates in atherosclerotic arteries

Excessive ECM degradation, destructive proteolytic

enzymes.Compromise diffusion of nutrients & wastes btw

vascular lumen & arterial wall, compress underlying media)

Degeneration & necrosis, thinning of arterial wall, expansion accelerates, risk of rupture increases

Risk factors:

Men older than 60 y/o

Smoking

Familial predisposition (atherosclerosis/HPT)

Hereditary defects in structural component of aorta ( Marfan syndromes)

Abdominal Aortic Aneurysm

Typically occur btw aortic bifurcation & renal arteries Can be saccular or fusiform Up to 15cm diameter, 25cm in length Variants: i) Inflammatory AAAs

characterized by dense periaortic dense fibrosis containing many macrophages, giant cells

ii) Mycotic AAAs

occur when circulating microorganisms (as in

bacteremia from a Salmonella gastroenteritis),

suppuration accelerate medial destruction, rapid dilation, rupture

Complications (ROCE) :

1) Rupture into peritoneal cavity/ retroperitoneal

tissues massive, fatal hemorrhage!!

2) Obstruction of a vessel branching off the aorta

( i.e. vertebralspinal cord, mesenteric arteries-GI

tract, renal-kidney, iliac-legs, reproductive organs)

3) Compression on adjacent structures ( ureter,

vertebrae)

4) Embolism from atheroma/mural thrombus

Symptoms of Abdominal Aortic Aneurysm

Asymptomatic

- pulsatile mass in abdomen

(incidentally discovered on abdominal examination,

calcification on plain abdominal X-ray, CT, ultrasound scan)

Symptomatic

- Abdominal pain/ back pain (need urgent surgery)

- due to rapid expanding aneurysm that causes pressure on

adjacent structures

- Fainting, hypotension (cardiovascular collapse), pain

that mimic renal colic pain due to leaking/ruptured aneurysm

Investigations for arterial disease Angiography CT scan X ray (chest, abdominal) Exercise ,resting ECG echocardiography Ultrasounds (carotid, abdominal, Doppler s

ultrasound)

Duplex ultrasonography Urine test for sugar, blood glucose Blood test for EST, CRP, serum cholesterol Ankle brachial pressure index (to look for PVD)

Prevention of arterial disease 1) Patients

Quit smoking Control blood sugar level Lower cholesterol & blood pressure level Eat food that are low in saturated fat (healthy diet) Exercise regularly, maintain BMI Sleep regularly (circadian rhythm) Regular body checkup Avoid contraceptive pills (choose alternatives), alcohol

(anti-ADH effects)

Drink lots of water, exercise foot & Wear elastic compression stockings for long flight travel

Take prophylaxis (anticoagulants)

2) Healthcare personnel

Monitor blood pressure, glucose, cholesterol level, body weight of the patient

Ultrasound scan of abdominal aorta for all men reaching 65 y/o

Give local anesthesia than general anesthesia during surgery

Give prophylaxis (anticoagulant) perioperatively

Prevention of arterial disease

Principles of Management of Arterial Disease 1) Non-surgical

Acute:

control ABCs (stop bleeding, resuscitation, treatment of thrombi or emboli)

obtain intravenous access, and administer oxygen, baseline laboratory studies, special investigations like ECG, chest radiograph, treatment of

thrombi or emboli (heparin infusion to increase APTT to 1.5 times normal

levels)

Contraindication in the presence of active internal bleeding, intracranial

bleeding, or bleeding at non-compressible sites.

Chronic:

Treat & monitor underlying diseases (eg.HPT, diabetes mellitus)

Regular risk factors assessment, screening, preventive measures

Principles of Management of Arterial Disease 2) Surgical

- Operative exploration (small vessels ligated, partial tear sutured or closed

with a vein patch, replace injured area with a segment of saphenous vein)

- Fasciotomy (split the deep fascia widely to relieve compartment pressure)

- Reconstructive surgery

- Insert stent-graft (endovascular repair)

- Angioplasty

- CABG

- Lumbar sympathectomy (increase blood supply to allow ulcer healing)

- Amputation