Vascular 1 Flashcards
What layer does atherosclerosis affect
- effects the intimal of the artery
what can atherosclerosis casue
- aneurysm and rupture
- occlusion by thrombus
- critical stenosis
what makes up a plaque
- Cells (SMC, macrophages and other white blood cells)
- ECM - collagen, elastin and prostaglandins
- Lipids
What is intermittent claudication
Pain in the limb brought on by exertion - it is relieved at rest, and recurs on similar effort
- muscle is in pain as it is not getting enough oxygen as it requires
How do you measure intermittent claudication
Measure it in terms of how far someone can walk on the flat
- usually can rest by standing for 2 or 3 minutes and then they can go on again
What condition can have a similar presentation to intermittent claudication
spinal ischaemia can have a similar presentation
What is critical limb ischaemia
- can be seen as the extreme of intermittent claudciation
- rest pain (constant pain and opiate analgesia) and tissue loss
- less than 50mmHg at ankle
- blood flow is so little that they get pain without doing anything
- often get pain at night
In critical limb ischaemia what is the blood pressure at the ankle
- less than 50mmHg at ankle
How common is peripheral artery disease
Population 55-74yrs:
• 25% asymptomatic PAD
• 5% – claudication
– 23% of claudicants will develop CLI over 10 yrs
if you measure the systolic pressure at the ankle and divide that by systolic pressure in the arm the lower it is the
higher the risk of death
what is the mortality of peripheral vascular disease
- PAD has a greater mortality rate than Cerebrovascular / Coronary artery disease
- 3% death per year
describe the outcomes of critical limb ischaemia
- 90% require reconstruction / angioplasty
- 25% amputation rate
- 50% die within 5 yrs (MI, CVA)
When examinaing patients with critical limb ischaemia what do you have to think about
- nerves - sensation - damaged first
- movement
- pain
What investigations do you use for peripheral vascular disease
- ABPI (confounders) -Duplex
- MRA / CTA
- Diagnostic angiogram
What are the risk factors for peripheral vascular disease
- smoking
- diabetes
- hypertension
- hypercholestrolemia
- hyperhomocysteinemia
- C reactive protein
What are the treatment options for peripheral vascular disease
• Conservative
– Lifestyle modification (exercise)
- diets - reduce refined sugar and fats
– Stop smoking
• Medical
– Risk factor optimisation
• Surgical
– Endovascular - Angioplasty
– Open - Surgical bypass
– Adjuncts
What medicines are used to control peripheral vascular disease
Diabetes control
- Reduce HbA1C by 1%- 21% reduction in complications
Cholesterol control
- Simvastatin 40mg -24% reduction in revascularisation
- HDL protective, LDL causes atherosclerosis
Blood pressure control
- HOPE study 26% reduction in events
Anti-platelets
- Aspirin 75mg 23% reduction in events
Anti-oxidants and vitamins
-Omega-3 fish oils
What happens in an angioplasty
- use a balloon and stent and expand the balloon
- this can expand the vessel and increae blood flow
- can also use a stent to keep the artery open
What are the risks and benefits of angioplasty
Risk
- failure to dilate
- re-stenosis
- surgical salvage e.g. if you rupture the vessel or cause dissection of the vessel
- amputation
- death
- contrast anaphylaxis
- renal dysfunction is less than 24 hours
benefits
- minimally invasive
- short stay
- quick recovery
what is bypass surgery preserved for
- preserved for patients with critical limb ischaemia
What is a prosthetic graft made out of
PTFE/Dacron
What veins do they use in a periperhal vascualr disease bypass surgery
- Long saphenous vein (most common)
- human umbilical vein
- PTFE (least common)
What are the risks and benefits for bypass surgery
Risks
- graft failures
- MI
- infection
- limb loss
- death
- in bed for longer
Benefits
- save limb
- retain indepedence
- wound healing
if patients are going to live longer than 2 years then it is better to do a …… in peripheral vascular disease
bypass than an angioplasty as bypass survives better at the moment
How do you deifne an aneurysm
Localised dilatation of an artery greater than twice normal diameter
Where do abdominal aortic aneurysms happen
Below the level at which the renal arteries come of
What is the commonest peripheral abdomen
Popliteal anuerysm
in patients with abdominal aortic aneurysm how common it is to have a popliteal aneurysm
- 10% of those with a AAA have a popliteal aneurysm
* 50% of those with a popliteal aneurysm have a AAA
How many popliteal aneruysms are bilateral
• 50% of popliteal aneurysms are bilateral
What is the definition of an abdominal aortic aneurysm
Aortic diameter >3cm
What is the growth of aneurysms a year
- tends to grow +/- 10% a year
What is the prevalence of an abdominal aortic aneurysm
- 9% prevalence in men over 65
* 12% incidence in hypertensive men
What is the mortality of an abdominal aortic aneurysm
• Mortality at rupture 90%
What is the pathogensis of abominal aortic aneurysms
- Intimal atherosclerosis
- Mural thrombus
- Destruction of elastic lamellae
inflammatory response is due to imbalance of matrix degrading proteinases and inhibitors
Autoimmune responses is increased
- cytokines
- chemoattractants
- peptide growth factors
What are the altered gene products found in abdominal aortic aneurysms
- Increased proteolysis (MMP-1, MMP-9)
* Increased inflammation – (cytokines, Chlamydia Ag / Ab, Adhesion molecules)
What are the risk factors for abdominal aortic aneurysms
- 1-5% positive family history
- ethnicity - higher in northern europeans compared to asians and africans
- smoking - relative risk is 2 and there is increased expansions
- hypercholesterolaemia
- hypertension
Name the three types of aneurysm
- saccular aneurysm
- fusiform aneurysm
- ruptured aneurysm
how is diabetes linked to aneurysm
- slower growth of an aneurysm
What are the indications for surgery for abdominal aortic aneurysm
- greater than 5.5cm in diameter
- rapid enlargement greater than 1cm a year
- symptomatic abdominal aortic aneurysm
How does open abdominal aortic aneurysm surgery work
- put a clamp on the aorta where it starts and ends
- open up the sac of the anueryms - take out the clot and then stitch the graft in
What is the risk of open abdominal aortic aneurysm surgery
- Mortality (5-10%)
- Myocardial Infarction
- Multi-organ failure
- Paraplegia
- Haemorrhage
- Infections (Wound / Graft)
- Fistulae
- Hernia
How does endovascular abdominal aortic anuerysm work
- use delivery sheaths to put stents up to seal in the healthy neck below the arteries going to kidneys and below all the aneurysms
- this reduces the pressure and over time the sac gets smaller
What are the beneftis and costs of endovascular abdominal anuerysm
pros
- 1% mortality rate
- decreased insult
- 2 day hospital stay
- can be percutaneous
cons
- cost - have to do surveillance
- surveillance
- re-interventions
- durability - 9 years after the procedure if you have an open surgery your mortality is less than the endovascualr abdominal anuerysm
who is screened for an abdominal aortic aneurysm
- men
- over aged 65
- more than 3cm go onto a surveillance programme
How do you screen abdominal aortic aneurysm
Single trans- abdominal ultrasound
What is an arterial dissection and what can cause it
- disruption to the intimal layer this could be due to iatrogenic, traumatic and spontaneous
- means that the blood cannot get into the vital branches of that blood vessel
- now have a channel of blood near where the wall is weak therefore you can get a localised aneurysm
What is the pain like in aortic dissection
- Severe tearing central to chest pain radiating to back
What are the risk factors for aortic dissection
- hypertension
Genetic/connective tissue
- bicuspid aortic valve
- marfans syndrome
- ehlers danlos
- any connective tissue disorder
How can you diagnose aortic dissection
CTA
What are the types of aortic dissection
Type A
Type B
Where are the types of aortic dissection
Type A
- nearest the heart
Type B
- further down after brachiopcehalic and caroitd and subclavian
What are the differences between type A and type B aortic dissection
Type A
- 95% mortality without immediate surgery (1% per hour)
Type B
- immediate and strict blood pressure control and monitoring - may need surgery to prevent sudden aortic catastrophy
What is the epidemiology of varicose veins
- 1/3 population 18-65 years
- Probably genetic link (familial)
- 120,000 Varicose vein procedures /year UK
What causes varicose veins
- happens when blood comes down the vein
- get a big column of blood sitting in the vein and then the vein ends up getting stretched
- back pressure from the little veins emptying into the veins get larger
- this is the varicose veins
What do you look for in history, examination and investigation of varicoe veins
History
- Family history
- previous DVT
- previous long bone
Examination
- bleeding
- skin problems
Investigation
- patent deep veins
- confirm root cause
How do you describe varicose veins
- Dilated
- tortuous
- incompetent
- refluxing
- aching if they have been standing for a while
How do you treat varicose veins
Conservative
- leg elevation
- class I compression hosiery
Medical
- topical relief
Surgical
- open ligation and stripping
- foam sclerotherapy - injection of a sclerosant that works as a poision against the lining of the vein that causes it to close up
- endovenous solutions - such as laser therapy - close the vein and force the blood to go in a vein that does work
Name the three surgical treatments for varicose veins
- open ligation and stripping
- foam sclerotherapy
- endovenous solutions
What are the complications of varicose veins
- Swelling
- Discomfort
- Itching
- Varicose eczema
- Haemosiderin deposition • Lipodermatosclerosis
- Bleeding
- Ulceration
what are the early and late compications of tratmetn in open ligation
Early
- bleeding
- bruising
- discomfort
- infection
- DVT/PE - life threatening complication
late
- recurrence
- parasthesia
What are the benefits of the endovenous surgery
- One hour treatment time
- Immediate ambulation
- Can be performed in physician’s office
- Much less expensive
- complications are mild and infrequent
