- Clinical science
Peripheral arterial disease (PAD) is characterized by narrowing and, in final stages, occlusion of the peripheral arteries due to atherosclerotic plaques. Smoking is the most important risk factor for developing PAD. PAD is often a silent disease, but patients may present with features of arterial insufficiency (intermittent claudication, reduced temperature and pulse rate in affected limb, skin discoloration, and trophic changes). On occasion, critical limb ischemia is the only presenting complaint. Segmental blood pressures and pulse volume recordings, particularly the ankle-brachial index (ABI), may support the diagnosis. Further imaging may confirm and assess the location and severity of arterial stenosis or occlusion. Treatment focuses on smoking cessation, graduated exercise, avoiding extremely cold temperatures, and modifying other cardiovascular risk factors. If conservative treatment fails, interventional and surgical management is recommended for low-risk patients with potential long-term success.
Prevalence: 8.5 million in the US
- Prevalence increases with age, starting from the age of 40
- US incidence rates are highest among African Americans, followed by Hispanics, who are at a slightly higher risk than non-hispanic whites.
- Peak incidence: 60–80 years of age
- Sex: ♂ = ♀
Epidemiological data refers to the US, unless otherwise specified.
Fontaine Classification of PAD
|Stage I|| |
|Silent disease|| |
|Intermittent claudication (10–35% of patients)|| |
|Absent or diminished pulses|
|Trophic changes|| |
|Rest pain|| |
|Critical limb ischemia|
A bruit, suggestive of arterial stenosis, may be heard in > 60–70% of cases with PAD!
- ABI is the ratio of systolic ankle blood pressure (BP) to systolic brachial BP
- Normally, ankle BP and brachial BP are equal (ABI = 1), or ankle BP is only slightly higher because of gravity (ABI ≥ 0.9)
- Differences in systolic BP indicate different pathologies:
- Exercise testing may be required if patients have a normal resting ABI 
While vascular imaging is not necessarily required for diagnosis, it is useful to determine the site and severity of arterial stenosis or occlusion (especially preoperatively and postoperatively)
- Digital subtraction angiography (DSA): gold standard
- CT angiography
- MR angiography
Measurements in diabetic or older patients may be inaccurate because of !
|Differential diagnosis of claudication|
|Patient characteristics||Clinical Features|
|Causes of arterial occlusion||Vasculitides|| |
| || |
|Popliteal entrapment syndrome|
|Cystic adventitial disease|| || |
|Mimics of arterial occlusion|
| || |
| || |
The differential diagnoses listed here are not exhaustive.
- Smoking cessation!
- Supervised graded exercise therapy
- Foot care (especially in diabetic patients)
- Avoid cold temperatures
- Modify cardiovascular risk factors: see
- PDE inhibitors (i.e., cilostazol): indicated when smoking cessation and exercise are unsuccessful
- Failure of conservative and pharmacologic treatment
- Inability to perform normal work or activities because of claudication
- No limitations to exercise by other disease (e.g., chronic heart failure) if claudication is improved
- Anatomy of the lesion allows low-risk and long-term success of intervention
- Minimally invasive interventional radiology: percutaneous transluminal angioplasty (PTA) with or without stenting
- Operative vascular reconstruction (bypass surgery): an autologous vein (e.g., great saphenous vein) is used to bypass the stenosis
- Last resort in the event of gangrene
- Definition: skin defect due to impaired blood flow to the lower extremities
- Etiology: most often seen in peripheral arterial disease
- Clinical features
- Differential diagnosis:
- Infection of ulcers; sepsis
- Surgical complications: bleeding, infection of vascular prosthesis, relapse
We list the most important complications. The selection is not exhaustive.