Definition
A.Peripheral vascular disease (PVD) refers to diseases of the blood vessels located outside the heart and brain.
B.Peripheral arterial disease (PAD) develops only in the arteries. PAD is the most common form of PVD.
Incidence
A.The Centers for Disease Control and Prevention (CDC) reports approximately 12% to 20% of people over age 60 develop PAD; it affects 15% to 20% of persons older than 70 years of age.
B.PAD affects about 8.5 million Americans.
C.The prevalence of PAD, both symptomatic and asymptomatic, is greater in men than in women, especially in young persons. At very advanced ages almost no differences exist between the sexes. However, age remains the main marker of PAD risk.
D.The estimated prevalence of intermittent claudication in persons aged 60 to 65 years is 35%. However, the prevalence in persons 10 years older (70–75 years) rises to 70%.
Pathogenesis
A.PVD is a slow and progressive circulation disorder caused by narrowing, blockage, or spasms in a blood vessel. PAD is considered a set of chronic or acute syndromes, generally derived from the presence of occlusive arterial disease, which causes inadequate blood flow to the limbs.
B.On most occasions, the underlying disease process is arteriosclerotic disease, mainly affecting the vascularization to the lower limbs.
C.From the pathophysiologic point of view, ischemia of the lower limbs can be classified as functional or critical due to an imbalance between the needs of the peripheral tissues and the blood supply.
D.Functional ischemia occurs when the blood flow is normal at rest but insufficient during exercise, presenting clinically as intermittent claudication.
E.Critical ischemia is produced when the reduction in blood flow results in a perfusion deficit at rest and is defined by the presence of pain at rest or trophic lesions in the legs.
Predisposing Factors
A.Age over 50.
B.Postmenopausal women have a higher risk.
C.Overweight and obesity.
D.Dyslipidemia.
E.Hyperhomocysteinemia.
F.History of cerebrovascular disease or stroke.
G.History of heart disease.
H.History of diabetes.
I.High blood pressure.
J.Family history of high cholesterol, high blood pressure, or PVD.
K.Kidney disease on hemodialysis.
L.Lifestyle choices that can increase risk of developing PVD include:
1.Sedentary lifestyle or not engaging in physical exercise.
2.Unhealthy dietary habits.
3.Smoking increases risk by seven times.
4.Drug use.
5.Excessive alcohol.
Subjective Data
A.Common complaints/symptoms.
1.The first signs of PVD begin slowly and irregularly.
2.Fatigue or cramping in legs and feet that gets worse with physical activity due to the lack of blood flow are the earliest signs the patients often report.
3.Leg cramps when lying in bed may occur.
4.Poor hair growth often below knees.
5.Legs and arms may turn reddish blue or pale.
6.Skin in the extremities may appear pale and thin.
7.Pulses in the extremities may be weak.
8.Ulcers and wounds in legs and toes that will not heal.
9.Toes may appear blue in color and the toenails become thick and opaque.
10.Patient often experiences severe burning in toes.
11.In severe cases, pain may occur even at rest, particularly at night when the legs are raised in bed.
12.In a small number of cases (often untreated), tissue death (gangrene) of a foot may result.
13.If an artery higher upstream is narrowed, such as the iliac artery, pain may be experienced in the thighs or buttocks while walking.
B.Common/typical scenario.
1.Patients will typically present with intermittent claudication, which is cramping with exercise that resolves with rest.
2.If the patient has severe disease progression, he or she may present with pain in the legs that occurs at rest.
C.Family and social history.
1.Ask about family history of any vascular disease or diabetes.
2.Ask about smoking, if the patient has a sedentary lifestyle or poor eating habits.
D.Review of systems.
1.Musculoskeletal: Ask about leg cramps, pain at rest, or if patients raise their legs at night.
2.Neurology: Ask about numbness or severe burning in toes.
3.Dermatology: Ask about discoloration of extremities, ulcers, or wounds that don’t heal, and/or nails that have become thick and opaque.
Physical Examination
A.Basic examination of PVD includes assessment for the presence of pulses in the lower limbs including the femoral, popliteal, pedal, and posterior tibial arteries.
B.Auscultation of the abdomen will enable identification of the presence of murmurs, which are indicative of disease in the aorta or the iliac arteries. Auscultation of the inguinal region may reveal
the presence of lesions in the external iliac or femoral bifurcation vessels.
C.Check the temperature, color, and capillary refill of the foot. Patients with claudication do not usually show a reduction in temperature or capillary filling.
D.Leg dangling test: A reduction in temperature and paleness, with or without cyanosis or dangling erythrosis, are common in patients with critical ischemia.
E.Patients with PAD have a higher risk for developing critical limb ischemia (CLI).
1.The patients with CLI should undergo expedited evaluation and treatment of factors that are known to increase the risk of amputation.
2.Patients with CLI in whom open surgical repair is anticipated should undergo assessment of cardiovascular risk.
3.Patients with CLI and skin breakdown should be referred to healthcare providers with specialized expertise in wound care.
4.Patients at risk for CLI (those with diabetes, neuropathy, chronic renal failure, or infection) who develop acute limb symptoms represent potential vascular emergencies and should be assessed immediately and treated by a specialist competent in treating vascular disease.
F.Chronic foot and leg ulcers (see Table 11.2).
G.Stages of PVD.
1.Stage I is characterized by the absence of symptoms. It includes patients who have an extensive occlusive arterial lesion in the legs, or have high risk but present no symptoms of arterial failure. In these situations, the patients may present with critical ischemia straight from an asymptomatic stage.
2.Stage II is characterized by the presence of intermittent claudication. The intermittent claudication that is typical in patients with PAD is defined as the appearance of pain in muscle masses caused by walking and which ceases immediately after stopping exercise. Of note: A great number of patients report pain in the legs associated with walking, but not with the presence of arterial disease. The stage II is itself divided into groups.
TABLE 11.2 How to Differentiate Foot Ulcer and Pain
Source: Armstrong, D. G., & Lavery, L. A. (1998, March 15). Diabetic foot ulcers: Prevention, diagnosis and classification. American Family Physician, 57(6):1325–1332. Retrieved from https://www.aafp.org/afp/1998/0315/p1325.html; Cleveland Clinic. (n.d.). Leg and foot ulcers. Retrieved from http://my.clevelandclinic.org/heart/disorders/vascular/legfootulcer.aspx; Frykberg, R. G. (2002, November 1). Diabetic foot ulcers: Pathogenesis and management. American Family Physician, 66(9), 1655–1663. Retrieved from http://www.aafp.org/afp/2002/1101/p1655.html; Jeffcoate, W. J., & Harding, K. G. (2003). Diabetic foot ulcers. The Lancet, 361(9368), 1545–1551. doi:10.1016/S0140-6736(03)13169-8
a.Stage IIa includes patients with non-invalidating claudication that impedes walking long distances.
b.Stage IIb refers to patients with short claudication or claudication that impedes activities of daily living.
3.Stage III constitutes a more advanced phase of ischemia and is characterized by the presence of symptoms at rest. The predominant symptom is usually pain, although the patient often reports paresthesia and hypoesthesia.
4.Stage IV is characterized by the presence of tropical lesions. It is due to the critical reduction of distal perfusion pressure, which is insufficient to maintain tissue tropism. These lesions are situated in the more distal areas of the limb, usually the toes, although on occasions they may present in the malleolus or the heel.
Diagnostic Tests
A.The diagnosis is usually made by the typical symptoms, history, and physical examination.
B.Homocysteine level to rule out hyperhomocysteinemia.
C.An ankle–brachial index (ABIs), toe–brachial index (TBI), and/or exercise ABI must be ordered.
D.Pulse volume recording or plethysmography: Recording the pulse wave volumes along the limb by plethysmography is particularly useful in patients in whom arterial calcification prevents a reliable recording of systolic pressures. Transmetatarsal or digital recording provides important information about the state of the vascularization in this zone.
E.Segmental pressure examination or Doppler recording of velocimetric wave can also provide very useful information by means of evaluating the changes in the different components of the arterial velocimetric wave.
F.Duplex ultrasound of the extremities is useful to diagnose anatomic location and degree of stenosis of PAD. May be used in select candidates for endovascular intervention, surgical bypass, and to select the sites of surgical anastomosis. This may also be used for surveillance following femoral-popliteal bypass using venous conduit (but not prosthetic grafts).
G.Imaging techniques are indicated if surgical or endovascular repair is contemplated after identification of a susceptible lesion.
1.Computed tomography angiography (CTA) produces an excellent arterial picture; however, it requires iodinated contrast. CTA may be considered to diagnose anatomic location and presence of significant stenosis in patients with lower extremity PAD and as a substitute for magnetic resonance angiography (MRA) for those patients with contraindications to MRA.
2.MRA has virtually replaced contrast arteriography for PAD diagnosis. The advantages of MRA