Peripheral Arterial Disease 1 Flashcards
What are some risk factors of PAD? 15.
- Diabetic
- Hypertension
- Hyperlipidemia
- Coronary artery disease (CAD)
- Previous history of CVA or MI
- Smoking
- Chronic renal insufficiency
- Age
- Family history
- Male
- Obesity
- Sedentary lifestyle
- Elevated levels of homocysteine
- Excessive levels of C-reactive protein
- History of radiation
What are some physical signs and symptoms of PAD? 8
- Skin changes
- Palpations
- Auscultations
- Limb pressures
- Claudication (intermittent)
- Ischemic rest pain
- Necrosis
- Pseudoclaudication
What are some skin changes seen in PAD? 9
- Pallor
- Rubor
- Dependent Rubor
- Cyanosis
- Temperature
- Nonhealing ischemic ulcers
- Gangrene
- Trophic changes (hair loss, nail thickening, skin thinning)
- Capillary refill time
In terms of PAD what are palpations?
- Pulses graded 0-4
- Aneurysms
In terms of PAD what can Bruits be caused by?
Significant stenosis
In stenosis how many bruits are not heard?
> 90%
In terms of signs and symptoms, what does the difference of limb pressures do?
Difference in limb pressures indicate disease, if there is a >20 mmHg in upper and lower extremity
What is claudication (intermittent)?
Lack of blood supply to a group of muscles
Is claudication reproducible?
Yes
What are common sites of claudication for PAD? 4
- Hip
- Buttock
- Thigh
- Calf
In terms of PAD sites of disease are always where in relation to the muscle group?
Proximal
How does claudication feel like?
Pain that occurs during exercise but subsides at rest
Ischemic rest pain is always an indicator of what?
Advanced multi-segment disease
In terms of ischemic rest pain, pain presents how?
Severe and constant
What does ischemic rest pain affect?
The dorsum of the foot and toes
Early onset of ischemic rest pain occurs when?
Only at night when the limb is not in a dependent position and may be relieved by lowering the foot or mildly exercising
In terms of ischemic rest pain, does rest relieve pain?
NO
What is the most severe symptom of PAD?
Tissue death
What is pseudoclaudication? Can it be reproducible?
- Pain caused by other factors
- No
What is the most common location of atherosclerotic disease?
Femoral artery at the adductor canal?
Atherosclerosis disease may appear how and affect what kind of levels?
- Focal or diffuse
- May affect any level or multiple levels
What are other common sites of Atherosclerosis besides common femoral?
At bifurcations and the popliteal artery
What is the most common cause of embolism?
From plaque breaking loose from the heart or a proximal aneurysm and traveling until it becomes lodged in a smaller vessel
What kind of plaque formation is embolism formed from?
Stenotic plaque formation
What is aneurysm? 3
- Dilation of all walls
- Trauma or atherosclerosis
- May contain a large amount of thrombus
Where are common areas of aneurysm? 3
- Abdominal aorta
- Femoral
- Popliteal arteries
What kind of upper extremity aneurysms are there? 2
- Subclavian aneurysms
- Ulnar aneurysms
In terms of subclavian aneurysms, embolization occur where?
Distal arteries in the hand
Subclavian aneurysms most commonly result as a result of what?
Compression of the subclavian artery due to the thoracic outlet syndrome
What are ulnar aneurysms due to?
Due to trauma from using the hand as a hammer
What are some sonographic features to look for in terms of aneurysms? 3
- Diameter increased >50%
- Colour doppler outlines thrombus and shows to and fro flow along the outer wall
- Note actual lumen size if there is thrombus
Where are measurements taken in terms of planes for aneurysm?
- Sag
- Trans
- AP
How do we measure for Aneurysms?
Outer wall to Outer wall
What does this image demonstrate?
Abdominal Aortic aneurysm
What are some uses for peripheral arterial duplex testing? 5
- Stenosis or occlusion
- Evaluate bypass grafts
- Presence of aneurysms
- Locate stenotic lesions Pre-surgery/ intervention
- Follow up poster surgery or effectiveness of medical therapy
What are some limitations of extremity duplex testing? 3
- Surface obstruction
- Obesity
- Calcified walls
What are some upper extremity limitations?
IV/ PICC lines
What are some patient history things to look out for? 12
- Exercise related claudicaiton
- Rest pain
- Paralysis
- Paresthesia
- Poikilothermia
- Ulceration/ gangrene of feet/ toe
- Previous therapeutic vascular procedure
- Arterial trauma
- Aneurysmal disease
- Abnormal ABI/WBI
- Absent peripheral pulses
- Bruit
What are some indications for a lower extremity exam?
Decrease in ABI >0.15 compared to previous exam
What is an indication for an upper extremity duplex test? 5
- Abnormal arterial arm pressure - pressure difference >20mmHg
- Thoracic outlet symptoms
- Evaluation prior to dialysis access
- Cold sensitivity
- Raynaud’s syndrome
What are some things we look for in 2D images of lower extremity exams? 2
- Identification of lie of vessels
- Plaque assessment
What are some beneficial things in terms of colour doppler that we see with lower extremity testing? 9
- Locate and follow vessels
- Vessel patency
- Flow direction
- Identify plaque
- Place doppler sample
- Stenosis or occlusion
- Evaluate bypass grafts
- Presence of aneurysm
- Follow up
What can pulsed doppler do? 3
- Confirm patency of vessels
- Flow speed
- Waveform assessment
What kind of probe do we use for a lower extremity arterial protocol?
5-7 mHz linear transducer
(3.5 mHz curvilinear for iliacs and CFAs)
What is the patient position for Lower extremity arterial protocols?
- Supine
- Head slightly elevated
- Thigh externally rotated and knee flexed
What are the arteries we assess in the lower extremity arterial protocol?
- Distal external iliac
- Common femoral artery
- Deep femoral artery
- Femoral artery
- Popliteal artery
- Bifurcation of tibal- perorenal trunk and anterior tibial arteries
- Dorsalis pedis and posterio tial arteries
During a lower extremity arterial protocol, when indicated what do we record? 4
Additional greyscale images from the:
1. Abdominal aorta
2. Common iliac arteries
3. External iliac arteries
4. Tibial arteries
What do we do when a stenosis is discovered?
“Walk” the sample gate through the stenotic area and obtain representative waveforms
1. Within 2cm proximal
2. Highs PSV
3. Distal to stenosis
When a stenosis is discovered after walking the sample volume what should we do? 2
- Document post stenotic turbulence and colour bruit
- Measure the diameter reduction in sagittal and transverse
In terms of a suspected stenosis, colour flow can do what?
Obscure the true luminal reduction if the gain is set too high, whenever possible, measure it in greyscale
What does PSV stand for?
Peak systolic volume
What are the PSV in lower extremity? (External iliac, common femoral, FA prox and distal, Pop)
During a lower extremity arterial protocol we should document additional findings with what?
Greyscale and colour imaging
What are things we should document during lower extremity protocol? 5 (things we would document if we see)
- Aneurysms
- Plaque
- Thrombus
- Wall irregularity
- AV fistula
When an occlusion is suspected what should we do? 2
- Documentation of flow with PW and any collateral branches
- Note the level of flow reconstitution when seen
REPEAT FOR THE CONTRALATERAL SIDE
What kind of probe is used for a upper extremity protocol?
7-10 MHz linear transducer is used, a 2-5 MHZ may be used to visualize proximal subclavian or innominate
What is the patient position for upper extremity exams?
Supine with a small pillow under the head with the arm externally rotated/ elbow flexed
What are the arteries that are assessed in the upper extremity?
- Subclavian
- Axillary artery
- Brachial
- Radial artery
- Ulnar artery
- Palmar arch if necessary
Label
What is the typical protocol for upper extremity duplex? 5
- Record greyscale, colour and spectral images in a sag views.
- Document additional grayscale and colour images at areas of suspected stenosis
- Classify the stenosis according to department diagnostic criteria
- Document any additional abnormal findings with grayscale and colour imaging
- Repeat for the contralateral side
What is the PSV of upper extremity arteries? (SCA, AXA, BrA, RA and UA, Palmar arch and digits)
What are some findings that we might see with Upper extremity?
- Aneurysms
- Plaque
- Thrombus
- Wall irregularity
- AV fistula
When doing a peripheral arterial interpretation what do we determine? 4
- Plaque location and characteristics
- PSV and flow characteristics
- V2/V1 PSV (VR)
- Any change in the spectral waveform
What is an interpretation of a normal?
Absence of a hemodynamically significant lesion <50%
What does a normal greyscale look like ?
No echoes are seen within the artery lumen
What does a normal colour doppler look like?
Colour dopplers fill the entire lumen from wall to wall
What does a normal doppler waveform and flow velocities look like?
- Normal waveforms are multiphasic and high resistance
- PSV are relatively uniform throughout the sampled arterial segment
What does an abnormal greyscale look like?
Intraluminal echoes are seen and decreased lumen can be measured
What does an abnormal colour doppler look like?
- Colour does not fill the entire lumen and colour jet is seen
- Colour mosaic seen due to post stenotic turbulence
What is a multiphasic waveform?
waveform crosses the baseline and contains both forward and reverse components
What kind of waveform is this?
Multiphasic
What is a monophasic waveform?
Waveform does not cross the baseline and blood flows in a single direction
What kind of waveform is this?
Monophasic
What is a high resistance waveform?
Sharp upstroke and brisk downstroke, with or without diastolic flow reversal
What kind of resistive waveforms are these?
High resistive
What is a intermediate resistive waveform?
Sharp upstroke, brisk downstroke, visible presence of a end-systolic notch and continuous forward flow throughout diastole that is above the baseline
What kind of resistance waveform is this?
Intermediate
What is a low resistance waveform?
Prolonged downstroke in late systole and continuous forward flow throughout diastole. Prolonged diastolic downslope with presence of pan-diastolic flow
What kind of resistive waveform is this?
Low resistive
What would we see with a stenosis? 5
- Focal velocity increase (>double that of the proximal arterial segment)(>50% diameter reduction) Vr > 2.0
- Focal velocity increase (>triple that of the proximal arterial segment)(>70% diameter reduction) Vr >3.0
- Spectral waveform changes
- Colour aliasing (proper settings0
- Potential colour bruit
What are some indirect signs of stenosis when a proximal velocity is difficult to obtain?3
- Increased velocities with luminal reduction and post stenotic turbulence
- Spectral waveform changes from one segment to the next
- Compare waveforms at the same site in the contralateral artery
What type pf waveform indicates occlusion?
Staccato indicates a distal occlusion
With an occlusion, how is flow detected?
Flow is not detected by colour or spectral doppler
Occlusion extent can be determined if what happens?
A large collateral is seen at the proximal and distal ends
If there is an occlusion we should use what?
Flow in an adjacent vein as a guide to identify an occluded artery. Always confirm by placing the doppler sample in the vessel lumen
Label
What are some medical treatments for occlusions? 5
- Modify the risk factors
- Exercise routine
- Antiplatelet medication
- Anticoagulation
- Thrombolysis
What are surgical treatments of stenosis/ occlusions? 4
- Bypass grafting
- Artherectomy
- Resection
- Amputation
What are some endovascular treatments for stenosis/ occlusions? 3
- Angioplasty
- Stent
- Intra-arterial directed thrombolysis
