Exercise claudication

Aggravation of cardiovascular disease (i.e., decreased exercise capacity in patients with angina pectoris, intermittent claudication, or peripheral arteriosclerosis)... 

A 42-year-old man presents with a chief complaint of intermittent claudication during exercise. His fomHy history is significant for the presence of cardiovascular disease on his fether s side, but not on his mother s side. Physical exam reveals xanthelasmas and bilateral tendon xanthomas. A plasma lipid profile reveals a cholesterol level of 340 mg/dL, with a high LDL/HDL ratio. He is given instructions for dietary modifications and a prescription for Zocor (simvastatin). 

Many disorders benefit from exercise (Pederson Saltin, 2005). These include asthma, cancer, chronic heart failure, coronary artery disease, chronic obstructive pulmonary disease (COPD), depression, type 1 diabetes melUtus, type 2 diabetes melUtus, hypertension, intermittent claudication, osteoarthritis, osteoporosis, rheumatoid arthritis and obesity. 

Contraindications to the use of 3 blockers are asthma and other bronchospastic conditions, severe bradycardia, atrioventricular blockade, bradycardia-tachycardia syndrome, and severe unstable left ventricular failure. Potential complications include fatigue, impaired exercise tolerance, insomnia, unpleasant dreams, worsening of claudication, and erectile dysfunction. 

Atherosclerosis can result in ischemia of peripheral muscles just as coronary artery disease causes cardiac ischemia. Pain (claudication) occurs in skeletal muscles, especially in the legs, during exercise and disappears with rest. Although claudication is not immediately life-threatening, peripheral artery disease is associated with increased mortality, can severely limit exercise tolerance, and may be associated with chronic ischemic ulcers and susceptibility to infection. 

Methylxanthines decrease blood viscosity and may improve blood flow under certain conditions. The mechanism of this action is not well defined, but the effect is exploited in the treatment of intermittent claudication with pentoxifylline, a dimethylxanthine agent. However, no evidence suggests that this therapy is superior to exercise conditioning. 

The clinical manifestations of PAD are associated with reduction in functional capacity and quality of life, but because of the systemic nature of the atherosclerotic process there is a strong association with coronary and carotid artery disease. Consequently, patients with PAD have an increased risk of cardiovascular and cerebrovascular ischemic events [myocardial infarction (Ml), ischemic stroke, and death] compared to the general population (4,5). In addition, these cardiovascular ischemic events are more frequent than ischemic limb events in any lower extremity PAD cohort, whether individuals present without symptoms or with atypical leg pain, classic claudication, or critical limb ischemia (6). Therefore, aggressive treatment of known risk factors for progression of atherosclerosis is warranted. In addition to tobacco cessation, encouragement of daily exercise and use of a low cholesterol, low salt diet, PAD patients should be offered therapies to reduce lipid levels, control blood pressure, control blood glucose in patients with diabetes mellitus, and offer other effective antiatherosclerotic strategies. A recent position paper... 

Several studies have revealed that statins have a beneficial effect on exercise performance in patients with claudication (13). Statins also improve endothelial function and have other... 

Intermittent claudication decreases exercise capacity and overall functional capacity, Impaired walking ability is coupled with the inability to perform activities of daily living and results in a decrease in overall quality of life (60). Pharmacologic and nonpharmacologic measures aimed in improving mobility and consequently the quality of life is important treatment goals for patients with PAD,... 

Mechanism of action that provides symptom relief with pentoxifylline is poorly understood but is thought to involve red blood cell deformability as well as a reduction in fibrinogen concentration, platelet adhesiveness and whole blood viscosity (75). The recommended dose of pentoxifylline is 400 mg three times daily with meals. Pentoxifylline causes a marginal but statistically significant improvement in pain-free and maximal walking distance (a net benefit of 44 m in the maximal distance walked on a treadmill (95% Cl, 0 14 to 0 74) based on meta-analyses of randomized, placebo-controlled, double-blind clinical trials (76). At the same time pentoxifylline does not increase the ABI at rest or after exercise (56). Pentoxifylline may be used to treat patients with intermittent claudication however, it is likely to be of marginal clinical importance (56,77). Medical therapies... 

Nehler MR, Hiatt WR. Exercise therapy for claudication. Ann Vase Surg 1999 13 109-1 14. 

Leng GC, Fowler B, Ernst E. Exercise for intermittent claudication. Cochrane Database Syst Rev 2000 2 CD000990. 

Gardner AW, Phoelman ET. Exercise rehabilitation programs for the treatment of claudication pain a meta-analysis. JAMA 1995 274 975-980. 

ACSM s Guidelines for Exercise Testing and Prescription. In Franklin BA, ed. Baltimore, MD, Lippincott Wiliams Wilkins, 2000.Girolami B, Bernardi E, Prins MH, et al. Treatment of intermittent claudication with physical training, smoking cessation, pentoxifylline, or nafronyla meta-analysis. Arch Intern Med 1999 159 337-345. 

Hiatt WR, Regensteiner JG, Creager MA, et al. Propionyl-Lcarnitine improves exercise performance and functional status in patients with claudication. Am J Med 2001 I 10(8) 616-622. 

Pentoxifylline (oxipentifylline) is a methylxanthine that antagonizes the vasoconstrictor effects of catecholamines and increases cyclic AMP concentrations, causing smooth muscle to relax. It has also been claimed to correct impaired microcirculation, by improving various factors that disturb blood rheology, and to reduce the generation of toxic free radicals from leukocytes during ischemic leg exercise in patients with intermittent claudication. Pentoxifylline has been used to suppress overproduction of tumor necrosis factor alfa in conditions such as falciparum malaria and rheumatoid arthritis and in transplant recipients, with varied success. 

After appropriate exercise therapy and therapeutic lifestyle changes have been implemented, patients who continue to experience severe intermittent claudication may benefit from additional pharmacologic therapy with cilostazol. 

Walking exercise programs for patients with PAD have been proven to result in an increase in walking duration and distance, an increase in pain-free walking, and a delayed onset of claudication by 179%.23,24,32,33,36-41 qj- ny aerobic exercise program... 

Stewart KJ, Hiatt WR, Regensteiner JG, Hirsch AT. Exercise training for claudication. N Engl 1 Med 2002 347 1941-1951. 

Gardner AW, Katzel LI, Sorkin JD, Goldberg AP. Effects of long-term exercise rehabilitation on claudication distances in patients with peripheral arterial disease a randomized controlled trial. J Cardiopulm Rehabil 2002 22 192-198. 

Langbein WE, Collins EG, Orebaugh C, et al. Increasing exercise tolerance of persons limited by claudication pain using polestriding. J Vase Surg 2002 35 887-893. 

Any attempt to evaluate therapy in intermittent claudication must take into account the following factors, (i) the clinical grade (ii) the arterial lesion (iii) the duration of claudication (iv) clear evidence of the absence of othei sources of pain with exercise. Since an assessment of the validity of the trial depends on an appreciation of these factors it is necessary to consider them in some detail. 

Frequent symptoms of lower extremity arterial disease (LEAD) are pressure, tightness, squeezing sensation, burning, and frank pain precipitated by leg exercise and relieved by rest. Intermittent claudication also may be present as fatigue in working skeletal muscles. Continuous pain must be differentiated from intermittent pain, because continuous pain may be a result of a sudden arterial occlusion with or without preexisting stenosis. Extremely severe ischemia or ischemic neuropathy, ulceration, or gangrene can also cause continuous pain. 

Wilson (87) divided patients with this condition into two groups (1) In the larger group, symptoms occurred during any activity or position involving extension of the lumbar spine that he termed postural cauda equina claudication, and (2) a smaller group of patients, with symptoms of the affected extremities after exercise that he described as ischemic cauda equine claudication. 

According to Blau et al. f88,89), the vascular factor is more important. In exercised animals, vessels inside the canal are dilated and if the canal is narrow increased blood supply is prevented, thus leading to ischemia of the cord and the nerve roots. However, this explanation is not shared by others (90). It does not explain why neurogenic claudication occurs in the lordotic position at rest. Pseudoclaudication can be caused by other orthopedic conditions of the hips, knees, and other joints. 

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