Peripheral arterial disease (PAD) encompasses a number of disorders that affect the arterial beds of the body aside from the coronary arteries. The arteries of the lower extremities are the main areas affected, and PAD is defined by an ankle-brachial index (ABI) of 0.90 or less. PAD is a manifestation of atherosclerosis and shares risk factors with coronary atherosclerosis. Data from the Framingham Heart Study determined the risk for developing PAD was increased when several common conditions were present including diabetes, hypercholesterolemia, cigarette smoking, and hypertension.
PAD patients are often asymptomatic, but may present with symptoms of impaired lower extremity arterial circulation including aching, pain, discomfort, and fatigue in leg muscles upon exertion. This type of leg ischemia is also referred to as intermittent claudication. Symptoms are relieved with rest. PAD is stratified based on presentation: asymptomatic, atypical leg pain, classic claudication, and critical limb ischemia.
Lower extremity pain is the most common clinical presentation, but clinical history and physical examination findings are not reliable for detecting PAD; therefore, diagnostic tests are critical. Diagnostic tests include ABI and exercise treadmill testing, as well as angiography if necessary for further workup. Table 4-1 lists key factors associated with the clinical presentation of PAD.
TABLE 4-1Clinical Presentation of Peripheral Arterial Disease |Favorite Table|Download (.pdf) TABLE 4-1Clinical Presentation of Peripheral Arterial Disease
|• Patients with PAD are likely to be 40 years of age and older with hypertension, hypercholesterolemia, diabetes, and/or a history of smoking. |
|Signs and Symptoms |
|• The clinical presentation of PAD is variable and includes symptoms ranging from no symptoms (typically early in the disease) to pain and discomfort. |
|• The two most common characteristics of PAD are intermittent claudication and pain at rest in the lower extremities. |
|• Intermittent claudication is regarded as the primary indicator of PAD. It is described as fatigue, discomfort, cramping, pain, or numbness in the affected extremities (typically the buttocks, thigh, or calf) during exercise and resolves within a few minutes at rest. |
|• Physical examination may reveal nonspecific signs of decreased blood flow to the extremities (eg, cool skin temperature, shiny skin, thickened toenails, and/or lack of hair on the calf). |
|Laboratory Tests |
|• None specific to PAD. |
|Other Diagnostic Tests |
|• An ABI is a simple, noninvasive, quantitative test that has been proven to be highly sensitive and specific in the diagnosis of PAD. |
The first steps in the treatment of PAD include exercise training and risk factor modification. Specific goals for the first steps of PAD treatment include the following:
Exercise rehabilitation through 30- to 45-minute sessions three times per week for 12 weeks with exercise to the point of symptom-limiting claudication
Control of comorbid conditions and risk factors
Diabetes control with hemoglobin A1c goal of less than ...