Vascular Flashcards
What is peripheral arterial disease?
Narrowing of arteries supplying limbs and periphery, reducing blood supply to these areas. Usually lower limb claudication.
What is intermittent claudication?
Cramping leg pain due to ischaemia in a limb, occurring during exertion and relieved by rest.
What is critical limb ischemia?
End-stage of peripheral arterial disease, where there is an inadequate supply of blood to a limb to allow it to function normally at rest. The features are pain at rest, non-healing ulcers and gangrene. There is a significant risk of losing the limb.
6Ps:
pain, pallor, pulseless, paralysis, parasethesia, perishing cold
What is acute limb ischemia?
Rapid onset limb ischemia - usually a clot in the arterial supply of the distal limb
Define necrosis and gangrene.
Necrosis = tissue death
Gangrene - due to inadequate blood supply
What is atherosclerosis?
Atheromas (fatty deposits in artery walls) and hardening and stiffening of the blood vessel walls (sclerosis). Caused by chronic inflammation and activation of immune system in artery wall. Lipids deposited first followed by fibrous atheromatous plaques. These cause stiffening, hypertension, heart strain; stenosis, and can rupture –> ischemia.
What is Leriche syndrome?
Leriche syndrome occurs with occlusion in the distal aorta or proximal common iliac artery. There is a clinical triad of:
Thigh/buttock claudication
Absent femoral pulses
Male impotence
How can you differentiate arterial and venous ulcers?
Arterial ulcers are caused by ischaemia secondary to an inadequate blood supply. They are painful, esp at night when elevated; peripheral, punched out, smaller, deeper, well defined borders, “punched-out”, reduced bleeding
Venous ulcers are caused by impaired drainage and pooling of blood in the legs.
Occur after a minor injury to the leg. Larger, superficial, irregular, gently sloping borders, gaiter area - mid-calf to ankle (more proximal),
signs of chronic venous insufficiency (e.g., haemosiderin staining and venous eczema), less painful and pain is worse on lowering the leg
How is peripheral arterial disease diagnosed?
Ankle-brachial pressure index (ABPI) = ratio of systolic blood pressure (SBP) in the ankle (around the lower calf) compared with the systolic blood pressure in the arm, taken manually using a Doppler probe.
0.9 – 1.3 = normal
0.6 – 0.9 = mild PAD
0.3 – 0.6 = moderate to severe PAD
< 0.3 = severe disease to critical ischaemic
An ABPI above 1.3 can indicate calcification of the arteries, making them difficult to compress. This is more common in diabetic patients.
What is the management for intermittent claudication?
Lifestyle change to manage modifiable risk factors for atherosclerosis - stop smoking, diet
Optimise medical treatment of comorbidities
Exercise training
Medical - atorvastatin 80mg, clopidogrel 75mg OD, naftidrofuryl oxalate (5-HT2 antagonist that dilates peripheral blood vessels)
Surgical - Endovascular angioplasty and stenting. Endarterectomy (cutting vessel open and removing plaque), bypass surgery. Think similar to cath lab
How is critical limb ischemia managed?
Urgent referral to vasc team, analgesia, revascularisation with EVAS, endarterectomy, bypass or amputation if unable to revascularise
How is acute limb ischemia managed?
Urgent referral to vascular.
Endovascular thrombolysis, endovascular thrombectomy, surgical thrombectomy, endarterectomy, bypass surgery, amputation if unable to revascularise.
What can cause stroke in someone with a DVT?
Septal defect (VSD, ASD)
What are thrombophilias? Give 5 examples
Thrombophilias are conditions that predispose patients to develop blood clots. Eg: Antiphospholipid syndrome Factor V Leiden Antithrombin deficiency Protein C or S deficiency Hyperhomocysteinaemia Prothombin gene variant Activated protein C resistance
How is VTE prevented?
Every patient admitted to hosp is assessed for risk, receive prophylaxis unless contraindicated (eg already on anticoags). This is usually with LMWH. Anti-embolic compression stocking are also used, contraindicated in significant peripheral artery disease.
How does a DVT present? Where do you measure the leg?
Calf or leg swelling 10cm below the tibial tuberosily, >3cm difference
Dilated superficial veins
Tenderness to the calf (particularly over the site of the deep veins)
Oedema
Colour changes to the leg
How is VTE diagnosed?
- D Dimer - exclude VTE where there is low suspicion. Raised in pneumonia, malignancy, HF, surgery, pregnancy
- Doppler - repeat in 1 week if negative but likely DVT
- CTPA or VQ for PE (eg CTPA CI in significant kidney impairment so cant have contrast)
How is VTE managed?
DOAC eg apixaban. Guideline change in 2020 from using LMWH.
Catheter directed thrombolysis for iliofemoral DVT.
Long term anticoag eg with DOAC:
3 months if reversible cause then review
6 months if uprovoked OR irreversible underlying cause eg APLS, cancer
IVC filter in rare cases of recurrent PE or unsuitable for anticoagulation.
How do you investigate an unprovoked DVT?
Review medical history, physical exam, baseliine blood results. Ask about FHx of VTE - hereditary thrombophilia. We no longer routinely do imaging.
If not continuing on anticoagulation, consider APLS antibodies
What are varicose veins?
Distended superficial veins measuring more than 3mm in diameter. Caused by valve incompetency from DVT, obesity, pregnancy, increasing age
May present with heavy sensation in legs, aching, oedema, cramps, restless legs, CVI
What are reticular veins?
Dilated blood vessels in the skin measuring less than 1-3mm in diameter
What is telangiectasia?
Dilated blood vessels in the skin measuring less than 1mm in diameter, also known as spider veins or thread veins.
What is chronic venous insufficiency and what are 3 signs?
When blood pools in the distal veins, the pressure (venous hypertension) causes the veins to leak small amounts of blood into the nearby tissues. The haemoglobin in this leaked blood breaks down to haemosiderin, which is deposited around the shins in the legs. This gives a brown discolouration to the lower legs.
Pooling of blood in the distal tissues results in inflammation –> dry, inflamed skin aka venous eczema.
The skin and soft tissues become fibrotic and tight, causing the lower legs to become narrow and hard, referred to as lipodermatosclerosis.
Inflammation of sc fat - panniculitis
Inverted champagne bottle appearance
Atrophie blanche - smooth white tissue
What is a saphenous varix? How can you diagnose it?
Dilated vein at saphenofemoral junction. Cough test - apply pressure at the SFJ and ask patient to cough, feel for thrill
