1. Non Atherosclerotic Peripheral Artery Disease
Ido Weinberg, MD MSc
Assistant Professor of Medicine
Harvard Medical School
Massachusetts General Hospital

2. Disclosure
I have no disclosures pertaining to this talk

3. This talk is based on a review:
I will mention other references that complement this review
The talk will focus on clinical aspects and diagnosis and less on treatment of each entity

4. Talk Outline Defining the problem When should NAPAD be suspected?
Diagnosis of exertional limb discomfort
Useful differentiating characteristics

5. Talk Outline Defining the problem When should NAPAD be suspected?
Diagnosis of exertional limb discomfort
Useful differentiating characteristics

6. Peripheral Artery Disease (PAD)
The presence of a stenosis or occlusion in the aorta or arteries of the limbs
This talk will focus on the lower extremity peripheral artery disease. We will mention but not focus on other vascular beds.
Circulation. 2011 Nov 1;124(18):

7. Intermittent Claudication
Recurring burning, aching, fatigue, or heaviness in the leg muscles with predictable level of walking, that
resolves with a predictable duration of rest (< 10 minutes)
Exertional leg pain is the focus of this talk.
These symptoms are very common in primary care and more common among cardiology patients
JAMA. 2001 Oct 3;286(13):

8. Some patients with claudication don’t have atherosclerosis or even a vascular problem
This is a central slide
Atherosclerosis is the most common cause of intermittent claudication
However there are many other causes. If you don’t think about these causes, chances are you won’t diagnose them.
The easiest way to remember the various causes is to divide them into vascular and non-vascular causes.
I will elaborate regarding many of the vascular causes during this presentation
However, one must remember to think about non vascular causes. Specifically, as PAD is a disease of the elderly, an open mind helps in making the diagnosis (Example 1: patient referred for critical limb ischemia and found to have acute gout. Example 2: Poor fitting insoles and foot pain in an elderly woman)
Circulation. 2012 Jul 10;126(2):213-22

9. PAD (atherosclerosis) is common0% 5%
10%
15%
20%
25%
30%
35%
29%
11.7%
19.8%
19.1%
14.5%
4.3%
When common risk factors were included, the prevalence of PAD was approximately one in three patients
PARTNERS5
Aged >70 years, or 50–69 years with a history diabetes or smoking
San Diego2
Mean age 66 years
Diehm4
Aged 65 years
Rotterdam3
Aged >55 years
NHANES1
Aged 70 years
Aged >40 years
1. Selvin E, Erlinger TP. Circulation. 2004;110: Criqui MH et al. Circulation. 1985;71: Diehm C et al. Atherosclerosis. 2004;172: Meijer WT et al. Arterioscler Thromb Vasc Biol. 1998;18: Hirsch AT et al. JAMA. 2001;286:

10. Non-Atherosclerotic PAD is Uncommon
0.03%
5-30%
0.25%
0.17%
JAMA. 2001;286:
Circulation. 2012 Jun 26;125(25):
Arthritis Rheum. 2004 Apr 15;51(2):264-8
Br J Surg. 1981 Jul;68(7):501-6
Circulation. 2012 Jul 10;126(2):213-22

11. Talk Outline Defining the problem When should NAPAD be suspected?
Diagnosis of exertional limb discomfort
Useful differentiating characteristics
The following clues should be noticed when evaluating ANY patient (i.e. the suspicion arises from the ‘standard’ evaluation of all patients with exertional leg discomfort). Specialized imaging and maneuvers are reserved when particular suspicion arises as will be discussed further in a bit

12. Consider Known Condition Involvement
Fibromuscular Dysplasia
Takayasu arteritis / Giant Cell Arteritis
Previous trauma
Athletisism
Severe venous disease
Spinal illness

13. Atherosclerosis is Age Dependent
Atherosclerosis is typical of older individuals. While atherosclerosis of the young has been described and is not uncommon, when young people present with symptoms think NAPAD. Also remember, NAPAD can present in older individuals.
J Vasc Surg. 2000 Jan;31(1 Pt 2):S1-S296

14. Disease Distribution and Appearance
PAD
NAPAD
Distribution:
Multiple vascular beds
Multiple and single vascular beds
Lower extremity
Lower and upper extremity
Specific syndrome-related distribution
Appearance:
Variable lesion length
Calcifications
Typical appearance
Presence of peri-vascular findings
Aortic arch and great vessels, distal disease (TAO), isolated mid aorta (idiopathic/vasculitis), external iliac
Typical appearance – Beading (FMD), Macaroni / halo, corkscrew (distal), redundant external iliac, redundant carotid/vertebral (FMD)
Peri-vascular findings – edema, compression

15. Ancillary Findings Constitutive symptoms Atypical ulcerations Rash
Superficial venous thrombosis

16. Atypical Ulcers

17. Telltale Rash

18. Popliteal Arterial Entrapment Syndrome
Young age
Symptoms: Acute vs. Neglected
Diagnostic maneuvers
Prompt surgical treatment
Pain, paresthesias, and cold feet after exercise
If neglected - ischemic rest pain and tissue necrosis
Forced plantar flexion – Disappearing popliteal signal

19. Types of PAES
J Vasc Surg. 2008 Dec;48(6 Suppl):61S-65S

20. Cystic adventitial disease
Middle-aged
Lingering symptoms
Inconsistent symptoms over years
Diagnosis:
Ishikawa sign
MRI
Hourglass/Scimitar sign
Ishikawa sign – Pedal pulses disappear with passive knee flexion

21. Diagnosis of Cystic Adventitial Disease
A – Angiogram with and without
forced plantar flexion
B – Sequential T2 weighted
MRI showing external compression of the popliteal artery A B
Radiographics. 2004 Mar-Apr;24(2):467-79

22. Endofibrosis of the iliac artery
Cyclists
Tailored exercise test
Non invasive imaging
Not only cyclists
Usually surgical treatment
Circulation. 1999 Aug 3;100(5):e38

23. Fibromuscular dysplasia
Middle aged Women > Men
Multi-system and “soft” symptoms / signs
Remember the various subtypes
More common than usually quoted
Diagnosis can often be incidental but on the other hand may be catastrophic
Renal, carotid, intracranial
Think about SAM
Circulation. 2012 Jun 26;125(25):
J Vasc Interv Radiol. 2011 Oct;22(10):1380-7

24. Thromboangiitis obliterans
Young male smokers
Absence of other CV risk factors
Upper and lower extremity
Distal and not proximal
Corkscrew collaterals
Superficial vein thrombosis
Once perhaps the most common form of ‘PAD’
Often difficult diagnosis to make in “grey” zone (middle aged, other risk factors)
Allen’s test

25. Intermittent Claudication in Vasculitis
Claudication is often not the sole presentation in vasculitis
Isolated mid-aortic involvement is not uncommon in Asia
Inflammatory marker and vascular inflammation are not present in “burned out” vasculitis
Long segments (macaroni)

26. Idiopathic mid-aortic syndrome, Hypoplastic arota
A form of coarctation (mid-aortic) or a congenital discrepancy between arterial size and the physiological need (hypoplastic)

27. Talk Outline Defining the problem When should NAPAD be suspected?
Diagnosis of exertional limb discomfort
Useful differentiating characteristics

28. Physical Findings in PAD
Absent or diminished peripheral pulses
Vascular bruits
Hair loss (?)
Dystrophic nail changes
Rapid elevation pallor or dependent rubor of the limb
Evidence of tissue loss (ulceration, gangrene)
JAMA. 2006 Feb 1;295(5):536-46

29. Hemodynamic Noninvasive Tests
Ankle-Brachial Index (ABI)
Exercise ABI
Segmental pressure examination
Pulse volume recordings

30. The Ankle-brachial Index (ABI)
Ankle SBP
Brachial SBP
ABI =
>1.3 Non-compressible
Normal
Borderline
Mild-Moderate
Severe
The ABI is the result of the ankle systolic pressure divided by the brachial systolic pressure.
The ABI can be measured simply and noninvasively in the medical office with an ABI meter.
Keywords: ABI
The ABI is 90% sensitive, 98% specific for detecting PAD (stenosis >50%) 30

31. Segmental Limb Pressures and Pulse Volume Recordings
150
110
108 62
ABI
146
100 84
0.56 31

32. Imaging Tests Duplex ultrasonography Computed tomographic angiography
Magnetic resonance angiography
Conventional contrast angiography

33. Arterial Duplex Ultrasound Testing
Diagnose anatomic location
Presence of stenosis 33

34. Elevated velocities and alliasing (turbulance) denote stenosis

35. Computed Tomographic Angiography (CTA)
Requires iodinated contrast
Requires ionizing radiation
Produces an excellent images
Unlike MRA, computed tomographic angiography, or CTA, requires the use of an iodinated contrast medium and ionizing radiation.
However, technological advances enable CTA to produce an excellent picture of the arteries of the lower extremity. 35

36. Magnetic Resonance Angiography (MRA)
Pros:
No ionizing radiation
Cons:
Requires local expertise
Gadolineum associated with Nephrogenic Systemic Fibrosis
Claustrophobia
Pacemaker/implantable cardioverter-defibrillator
Obesity
MRA has virtually replaced contrast arteriography in helping to establish the diagnosis of PAD.
MRA not only provides an excellent picture of the arteries but also has the advantage of not using ionizing radiation.
Instead, MRA uses a noniodine-based intravenous contrast medium that rarely causes renal insufficiency or allergic reaction.
However, approximately 10% of patients cannot be assessed by using MRA because of claustrophobia, a pacemaker or implantable cardioverter-defibrillator, or obesity.
Keywords: PAD 36

37. Where is the lesion located?

38. Lesion location – Cont’d

39. NAPAD Diagnostic Algorithm

40. Talk Outline Defining the problem When should NAPAD be suspected?
Diagnosis of exertional limb discomfort
Useful differentiating characteristics

41. Tips to differentiate atherosclerosis from NAPAD – Clinical clues
Age of onset
Sex predominance
Symptom trigger
Time to symptom resolution with rest
Additional symptoms
Physical examination and maneuvers

42. Rapid fire…

43. Which lesion is typical of PAD?

44. What will this patient complain of?

45. What is this patient’s likely gender?

46. Can this patient present with intermittent claudication?

47. Summary – Think about NAPAD
NAPAD are rare compared to Atherosclerotic PAD
Most NAPAD can be suspected clinically and from standard imaging studies
Think about NAPAD in every patient who presents with exertional leg discomfort
If NAPAD is diagnosed, tailor treatment accordingly

48. Thank you