Disease of the Peripheral Arteries, Aorta, and Vasculitis Flashcards
What is intermittent claudication?
- Cramping, tightness, fatigue
- Involves buttock, hip, thigh, calf, foot
- Exercised-induced
- Distance to claudication is unchanged
- Does not occur with standing
- Relieved by rest (Usually within 5 minutes)
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Only ~ 1/3 of the PAD patients experience classic IC
- remaining have either atypical symptoms or are asymptomatic
Why is peripheral artery disease (PAD) so difficult to treat?
PAD patients are not getting proper care
- Among hypercholesterolemic patients:
- 68% of CAD patients were on lipid lowering therapy
- 46% of PAD patients on lipid lowering therapy (p=0.08)
- 94% of CAD patients were told to follow a low fat/cholesterol diet
- 83% of PAD patients told the same (p=0.01)
- Exercise:
- 71% of CAD patients exercised
- 50% of PAD patients exercised (p<0.01)
- 74% of CAD patients were told to exercise by their physician
- 46% of PAD patients were told to exercise (p<0.01)
What is done on physical examination for PAD?
- Auscultate the abdomen, femoral arteries, for the presence of bruits
- Palpate for the presence of an abdominal aortic aneurysm
- Palpate the femoral, popliteal, posterior tibial, and dorsalis pedis pulses
- Inspect the feet for ulcers, fissures, calluses, tinea, tendinous xanthomas, and evaluate overall skin care
There can be a congenital absence of ankle pulses
How are pulses graded?
- normal: 2
- diminished: 1
- absent: 0
What can be inspected in a patient with PAD?
- Hair loss
- Muscle atrophy
- Thickened and brittle toenails
- Smooth and shiny skin
- Subcutaneous fat atrophy
- Skin fissures
- Ulceration
- Gangrene
What is the difference betwen pallor and dependent rubor in PAD patients?
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Pallor
- Supine position or elevation
-
Dependent rubor
- Filling of dilated skin capillaries with deoxygenated blood
What are some noninvasive evaluations for PAD?
- Ankle-Brachial Index
- Ankle-Toe Index
- Exercise treadmill testing
- Segmental limb pressures
- Pulse volume recordings
- Arterial Duplex ultrasonography
- Doppler Ultrasonography
- CT Angio
- MRI
What is ABI?
ABI = Ankle systolic pressure/ Brachial artery systolic pressure
- Systolic blood pressures are measured in each arm and then at each Dorsalis Pedis and Posterior Tibialis
- ABI for each leg is calculated by dividing the higher of either the PT or DP by the higher of the two brachial
- If normal, repeat on treadmill
How can you determine the severity of PAD using ABI?
-
ABI values:
- Noncompressible vessels: > 1.30
- Normal: 0.90–1.30
- Mild: 0.70–0.89
- Moderate: 0.40–0.69
- Severe: < 0.40
- ABI<0.9 is up to 95% sensitive and specific for detecting angiographic arterial disease
- ABI does not define the disease location
What radiographic tool is used to aid in PAD diagnosis?
Ultrasonography
- Vessel anatomic characteristics
- Functional significance of stenosis
- Color flow Doppler:
- Twofold increase in PSV→ ≥ 50% stenosis
- Threefold increase in PSV→ ≥ 75% stenosis
What are the treatment goals for patients with PAD?
- Smoking cessation
- Lipid control
- LDL-C, ≤ 100 mg/dL (Ideally <70)
- BP control
- Blood Pressure <140/90)
- Use ACE inhibitors
- B-blockers acceptable
- Diabetes control
- HbA1C ≤ 7.0%
- Antiplatelet therapy
- ASA, clopidogrel
- Achieving ideal body weight
- Exercise
How is cigarette smoking involved in PAD?
- Two to fivefold increased risk of PAD
- Approximately 84%-90% of patients with claudication are current or ex-smokers
- Smoking increases the risk of PAD >> CAD
- Diagnosis of PVD is made 10 years earlier among smokers
- Amount and duration of tobacco use correlate directly with the development of PAD
- Patients that continue to smoke experience
- More common progression to CLI and limb loss
- Decreased the LE arterial bypass patency rates
How is diabetes mellitus involved in PAD?
- Two to fourfold increased risk of PAD
-
Different anatomic characteristics:
- Extensive disease
- Greater propensity for vascular calcification
- Infrapopliteal disease more common
- Among patients with PAD diabetics more likely to have an amputation
What is the importance of the reudction in HbA1C?
UK prospective diabetes study (UKPDS):
- Risk reduction per 1% reduction in HgA1c:
- Risk for amputation: 37%
- Death from PAD: 43%
- Myocardial infarction: 14%
- Stroke: 12%
- Heart failure: 16%
When are pentoxifylline and cilostazol used for PAD?
only in emergencies
What is the contraindication for cilostazol?
heart failure
Exercise: Just Do It! (Nike)
Why is it beneficial?
- Supervised exercise walking programs improve symptoms of claudication
- Sessions of 30 min in duration
- At least 3 times a week
- At least 6 months
-
Possible mechanisms:
- Formation of collateral vessels
- Improvement of endothelium-depended vasodilators
- Improvement of muscle metabolism
- Improved walking efficiency
What two antiplatelet drugs are beneficial in PAD treatment?
What drug is ineffective?
- Aspirin, typically in daily doses of 75 to 325 mg, is recommended (Level of Evidence: B)
- Clopidogrel (75 mg per day) is recommended as a safe and effective alternative antiplatelet therapy to aspirin (Level of Evidence: B)
- Warfarin has no benefits and can be potentially harmful ⇒ ↑ risk of major bleeding
Indications for Revascularization for Intermittent Claudication:
- Lifestyle-limiting symptoms
- Continued disability despite appropriate non-surgical management
- Technically feasible revascularization options exist
- Expectation of favorable risk/benefit ratio
- Revascularization options:
- Percutaneous
- Surgical
- Combined
What patients are at risk for acute aortic dissection (AoD)?
Consider acute aortic dissection in patients with:
- Chest, back or abdominal pain
- Syncope
- Symptoms consistent with perfusion deficit
- CNS, mesenteric, myocardial, or limb ischemia
What is seen on physical exam in a patient with AoD?
- Vital signs at baseline
- Cardiac exam- Murmurs , heaves, and pulses
- Pulmonary exam- Rales
- Neuro exam: Focal deficits
What is the differential diagnosis for AoD?
What do you look for on CxR, ECG, echocardiogram and CT chest?
-
Differential diagnoses:
- Acute myocardial infarction
- Aortic dissection
- Aortic aneurysm
- Pulmonary embolism
- Chest X Ray: Heart size and contour
- ECG: Identify ischemia, pericardial effusion,
- Echocardiogram: Look at the heart valves, cardiac function, aortic disease
- CT Chest: Look for pulmonary embolism or aortic dissection
What are the high risk features associated with AoD?
What is done in a patient with two or more high risk features?
immediate surgical consultation and arrange for expedited aortic imaging
