Recognizing The Damaging Impact Of PAD
Jeffrey Bowman DPM MS
A recent Lancet report noted that in 2010, 202 million people worldwide had peripheral artery disease (PAD).1 Consider the following statistics about PAD and related complications.2
• Those who smoke are two to three times more likely to have lower extremity PAD.
• Patients with PAD are four to five times more likely to suffer a transient ischemic attack or stroke.
• Those with PAD are two to six times more likely to die from coronary heart disease.
Peripheral artery disease refers to a group of disorders leading to progressive stenosis, occlusion or aneurysmal dilation of the aorta and its non-coronary branches. These branches include: carotids, the upper extremity blood vessels, viscera and lower extremity blood vessels.3
The most common cause of PAD is atherosclerosis.4 Other risk factors for PAD include: smoking, diabetes, hypertension, increased levels of cholesterol and lipids, arteriosclerosis and family history.3,4
The presence of diabetes can complicate PAD in several ways.3
• Patients with diabetes tend to be affected by PAD more severely than those without diabetes.
• Atherosclerosis in patients with diabetes is more diffuse and occurs over a much longer course of the artery than in patients without diabetes.
• Atherosclerosis tends to occur earlier in those with diabetes.
• Atherosclerosis tends to progress more aggressively in people with diabetes versus people without diabetes.3
Keys To Diagnosis
When working up a patient with suspected PAD, clinicians can refer to the Fontaine classification of PAD based on symptoms.3,5
I. Asymptomatic PAD
III. Ischemic rest pain
IV. Ulceration and tissue loss
Claudication. Peripheral arterial disease can cause pain in the leg when there is exertion.3,5 The pain is relieved by rest and is reproducible with walking.
Often, exercise-induced ischemia causes this pain. However, one should not confuse claudication with muscular pain or leg cramps. Muscular pain not only occurs with activity but also with standing or changing positions. Leg cramps can be associated with many conditions but are generally not a sign of ischemia.
Critical limb ischemia. Peripheral arterial disease can present with ischemic rest pain, which is a more severe form of the disease. The pain can worsen with elevation of the foot and leg.
Physicians should consider critical limb ischemia as Type III PAD due to pain at rest.3 The rest pain is due to severely compromised or occluded vasculature. Patients will more than likely have pain with elevation of the foot or leg as the blood flow further reduces. As the leg lowers, you will notice increased dependent ruborin the foot.
Acute limb ischemia. Thrombosis of an atherosclerotic plaque most likely causes this symptom.3Typical signs and symptoms include: pain, paralysis, paresthesias, lack of a pulse, pallor and polar.
Asymptomatic. This does not mean that arterial function is normal.3 Individuals may not have the classic symptom of exercise-induced pain but they may have noticed a reduction in speed and balance. Most of these patients have systemic atherosclerotic disease and are at high risk for lower extremity complications.
Other signs and symptoms of PAD include:
• coldness in the foot, especially in comparison to the other side;
• leg numbness or weakness;
• change in color of the leg;
• hair loss to the legs or tops of feet;
• slower growth of toenails; and
• weak pulses in legs and feet.2
Although PAD does not cause ulcerations, once they are present, PAD can delay, if not worsen, the healing process.2
Possible Treatment Options
Treatment can include risk factor modification.2,3 This can include lipid lowering medications, anti-hypertensive medications, blood sugar management, smoking cessation, daily foot checks and anti-platelet medications. If necessary, surgical intervention can include bypass surgery.
1. Fowkes FG, Rudan D, Rudan I, Aboyans V, Denenberg JO, McDermott MM, et al. Comparison of global estimates of prevalence and risk factors for peripheral artery disease in 2000 and 2010: a systematic review and analysis. Lancet. 2013 Jul 31.doi: 10.1016/S0140-6736(13)61249-0. (Epub ahead of print).
2. Zgonis T. Surgical Reconstruction of the Diabetic Foot and Ankle. Lippincott Williams & Wilkins, Philadelphia, 2009.
3. Cuculich PS, Kates AM. The Washington Manual Cardiology Subspecialty Consult. Lippincott Williams & Wilkins, Philadelphia, 2008.
4. Kumar V, Abbas AK, Cotran RS et al. Robbins Basic Pathology. Saunders, Philadelphia, 2007.
5. Mayo Clinic. Peripheral artery disease (PAD). Available at www.MayoClinic.com . Published June 22, 2013. Accessed August 20, 2013.