Free Shipping on orders over $99

Peripheral Arterial Disease: Risk factors, diagnosis, investigations and treatment options

Diabetes, Heart, Stroke | March 4, 2015 | Author: The Super Pharmacist

heart disease, heart

Peripheral Arterial Disease: Risk factors, diagnosis, investigations and treatment options

Peripheral arterial disease or PAD is a form of atherosclerosis that leads to a narrowing or blockage of the arteries in the arms or legs. This narrowing of the arteries makes it more difficult for blood to flow to the extremities. When the tissues need increased blood flow, such as during movement, the narrowed arteries do not allow sufficient blood to reach the extremities. This insufficient blood flow causes pain, called claudication. In many ways, claudication in the arms and legs is similar to angina that occurs in the heart; both sensations are caused by insufficient blood flow to tissues. In severe peripheral arterial disease (also called peripheral artery disease), claudication may occur even at rest.

Clinical features of peripheral arterial disease

Classically, the patient with PAD will experience pain during exercise; even an exercise as mild as walking. That pain will go away once the patient rests. This correlates to the time in which the tissues are starved of oxygen-rich blood (pain occurs) and then blood flow is restored (pain goes away). Since older people often feel pain in their legs when they walk due to things such as arthritis or simple joint stiffness, peripheral arterial disease and claudication can be difficult to recognise. Patients tend to associate these feelings with old age and their doctors dismiss the problem as a consequence of aging.

The pain associated with peripheral arterial disease is fundamentally different from other age-related pains of the arms and legs.

  • First, claudication does not occur in the joints, but usually affects the muscles. Pain in the calf muscle is most common, but may occur in the foot, thigh, buttock or the arms and hands.
     
  • Second, muscle stiffness of advanced age/strenuous exercise usually occurs long after the exercise has stopped, even the next day. PAD pain occurs during exercise and resolves rather quickly. PAD may also cause skin discoloration in the extremities, which presents as paleness or even blueness from lack of blood flow. Wounds in the extremities may be slow to heal and in severe cases, ulcers and gangrene are possible.

Risk factors for peripheral arterial disease

Since peripheral arterial disease is caused by atherosclerosis, many of the risk factors for atherosclerosis that occurs in the heart and in the large arteries are the same as those in the smaller blood vessels in the arms and legs. These may include:

Hereditary. Peripheral arterial disease tends to run in families. People who have close relatives with PAD are more likely to develop the condition. 

Smokers. Individuals who smoke cigarettes are significantly more likely to develop atherosclerosis and, consequently, peripheral arterial disease. In fact, smoking seems to be a more significant risk factor in PAD that it is in coronary artery disease. In other words, smokers have an even greater likelihood of developing peripheral arterial disease than coronary heart disease (but still have a higher likelihood of developing both diseases than non-smokers). 

High blood pressure, diabetes, and abnormal levels of cholesterol are strong risk factors for peripheral arterial disease.

Not all traditional risk factors for atherosclerosis apply to PAD, however. For instance, men and women appear to develop PAD roughly at the same rate, while men tend to develop coronary artery disease in greater numbers than women do, especially at younger ages. In fact, women may be even more likely to develop PAD than men are. 

The American College of Cardiology and the American Heart Association have identified several groups of individuals who have a higher prevalence of peripheral arterial disease:

  • Age ≥70 years
  • Age 50 to 69 years with a history of smoking or diabetes
  • Age 40 to 49 with diabetes and at least one other risk factor for atherosclerosis
  • Leg symptoms suggestive of claudication with exertion or ischemic pain at rest
  • Abnormal lower extremity pulse examination
  • Known atherosclerosis at other sites (e.g. coronary, carotid, renal artery disease)

Diagnostic studies

Physical examination

Some basic diagnostic “studies” may occur during physical examination. For example, physicians may be able to detect unusually weak pulses in the arteries of the legs (i.e. pedal pulses). If blood pressure is not the same when it is measured in both arms (a difference of greater than 10 mmHg), this suggests one of the arms may have peripheral arterial disease. In fact, comparing blood pressure measurements of various parts of the body (e.g. ankle versus upper arm, wrist versus upper arm, toes versus upper arm, etc.) can be indicative of the diagnosis of PAD.

Doppler ultrasound

When available, physicians may be able to perform a bedside ultrasound study to measure what is called the resting ankle-brachial systolic pressure index or ABI. In other cases, patients may need to go to a diagnostic laboratory for this testing. The clinician uses Doppler ultrasound to carefully measure the systolic blood pressure (the top number in a blood pressure reading) in both the upper arm and the ankle. The two measurements are compared in a simple ratio of ankle blood pressure to brachial blood pressure. An ABI of less than 0.90 is highly indicative of peripheral arterial disease. An ABI of less than 0.4 is usually associated with leg pain at rest and possible tissue damage.

Vascular imaging

Arteriography, also known as angiography of the arteries, is the gold standard for diagnosing peripheral arterial disease. While arteriography is the gold standard, patients do not always need to use this expensive test if the symptoms, physical diagnosis, and less invasive testing can confirm diagnosis. If arteriography is necessary, the clinician and patient has three choices (if the technology is available in their medical center).

1. The standard approach is to place a thin tube called a cannula into an artery, usually starting in the upper, interior thigh. The cannula is moved to various locations within the blood vessel system and a small amount of radiocontrast dye is released. This dye travels through the arteries showing up on special x-rays called fluoroscopy. The physician can detect areas of narrowing or blockage using this technique.

2. Some advanced medical centers have multi-detector computed tomography, which also requires the use of contrast dye but can provide a rapid diagnosis.

3. The third option is related to an MRI and is called an MRA or magnetic resonance angiography. In an MRA, contrast is injected and an MRI machine is used to create high-resolution images of the blood vessels. All three diagnostic approaches are expensive and again may not be necessary if “low-tech” studies provide the diagnosis.

Treatment of peripheral arterial disease

Treatment for PAD involves a combination of risk factor management, drug treatment, and possibly invasive procedures. Since peripheral arterial disease is progressive, the progression can be halted (and possibly reversed) by lifestyle interventions and atherosclerosis treatment.

  • Quit smoking. Anyone with PAD should undergo an aggressive smoking cessation program if necessary. 
  • Exercise. Supervised exercise programs can be highly effective in treating PAD. 
  • Blood sugar monotoring. Patients with diabetes should maintain strict blood glucose control.
  • Blood pressure reduction. People with high blood pressure should receive effective treatment.
  • Medication. Drugs that inhibit the ability of platelets to stick together may or may not be beneficial, but are often used. These antiplatelet drugs include aspirin and clopidogrel. Intermittent use of mechanical compression garments may be helpful at reducing the symptoms of claudication. 

Treatments that are not helpful and may be harmful include warfarin, hormone replacement therapy, garlic, vitamin D supplements, and chelation therapy. In severe cases of peripheral arterial disease, surgical treatments may be necessary.

Angioplasty and stents

When possible, experts recommend the use of angioplasty and stents in troublesome arteries.

In this treatment, a thin catheter is inserted into an artery in the upper leg and advanced to the site of narrowing or blockage. A balloon is used to expand the artery and then a stent or metal cylinder is deployed that holds the artery open. This stent permits greater blood flow through the diseased artery and reduces symptoms of claudication in the affected extremity.

 

Revascularisation surgery

In the worst cases of PAD, revascularisation surgery may be necessary. This approach is very similar to a CABG (pronounced cabbage) procedure in the heart, also known as a coronary artery bypass graft. An artery or vein is harvested from somewhere in the body and then reconnected before and after a place of arterial narrowing. Blood flows through the transplanted artery in addition to or instead of the original, blocked artery. Arterial surgery is only used when angioplasty and stents are not an option.

www.superpharmacy.com.au  Australia’s best online discount chemist

References

Murabito JM, Guo CY, Fox CS, D'Agostino RB. Heritability of the ankle-brachial index: the Framingham Offspring study. Am J Epidemiol. Nov 15 2006;164(10):963-968.

Agarwal S. The association of active and passive smoking with peripheral arterial disease: results from NHANES 1999-2004. Angiology. Jun-Jul 2009;60(3):335-345.

Powell JT, Greenhalgh RM. Continued smoking and the results of vascular reconstruction. Br J Surg. Aug 1994;81(8):1242.

Lu L, Mackay DF, Pell JP. Meta-analysis of the association between cigarette smoking and peripheral arterial disease. Heart. Mar 2014;100(5):414-423.

Fowkes FG, Housley E, Riemersma RA, et al. Smoking, lipids, glucose intolerance, and blood pressure as risk factors for peripheral atherosclerosis compared with ischemic heart disease in the Edinburgh Artery Study. Am J Epidemiol. Feb 15 1992;135(4):331-340.

Rapsomaniki E, Timmis A, George J, et al. Blood pressure and incidence of twelve cardiovascular diseases: lifetime risks, healthy life-years lost, and age-specific associations in 1.25 million people. Lancet. May 31 2014;383(9932):1899-1911.

Murabito JM, D'Agostino RB, Silbershatz H, Wilson WF. Intermittent claudication. A risk profile from The Framingham Heart Study. Circulation. Jul 1 1997;96(1):44-49.

Ridker PM, Stampfer MJ, Rifai N. Novel risk factors for systemic atherosclerosis: a comparison of C-reactive protein, fibrinogen, homocysteine, lipoprotein(a), and standard cholesterol screening as predictors of peripheral arterial disease. JAMA. May 16 2001;285(19):2481-2485.

Newman AB, Siscovick DS, Manolio TA, et al. Ankle-arm index as a marker of atherosclerosis in the Cardiovascular Health Study. Cardiovascular Heart Study (CHS) Collaborative Research Group. Circulation. Sep 1993;88(3):837-845.

Hiramoto JS, Katz R, Weisman S, Conte M. Gender-specific risk factors for peripheral artery disease in a voluntary screening population. J Am Heart Assoc. 2014;3(2):e000651.

Clark CE, Taylor RS, Shore AC, Ukoumunne OC, Campbell JL. Association of a difference in systolic blood pressure between arms with vascular disease and mortality: a systematic review and meta-analysis. Lancet. Mar 10 2012;379(9819):905-914.

Norgren L, Hiatt WR, Dormandy JA, Nehler MR, Harris KA, Fowkes FG. Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC II). J Vasc Surg. Jan 2007;45 Suppl S:S5-67.

Hankey GJ, Norman PE, Eikelboom JW. Medical treatment of peripheral arterial disease. JAMA. Feb 1 2006;295(5):547-553.

McDermott MM, Liu K, Ferrucci L, et al. Physical performance in peripheral arterial disease: a slower rate of decline in patients who walk more. Ann Intern Med. Jan 3 2006;144(1):10-20.

Murphy TP, Cutlip DE, Regensteiner JG, et al. Supervised exercise versus primary stenting for claudication resulting from aortoiliac peripheral artery disease: six-month outcomes from the claudication: exercise versus endoluminal revascularization (CLEVER) study. Circulation. Jan 3 2012;125(1):130-139.

Tendera M, Aboyans V, Bartelink ML, et al. ESC Guidelines on the diagnosis and treatment of peripheral artery diseases: Document covering atherosclerotic disease of extracranial carotid and vertebral, mesenteric, renal, upper and lower extremity arteries: the Task Force on the Diagnosis and Treatment of Peripheral Artery Diseases of the European Society of Cardiology (ESC). Eur Heart J. Nov 2011;32(22):2851-2906.

de Haro J, Acin F, Florez A, Bleda S, Fernandez JL. A prospective randomized controlled study with intermittent mechanical compression of the calf in patients with claudication. J Vasc Surg. Apr 2010;51(4):857-862.

Hirsch AT, Haskal ZJ, Hertzer NR, et al. ACC/AHA 2005 Practice Guidelines for the management of patients with peripheral arterial disease (lower extremity, renal, mesenteric, and abdominal aortic): a collaborative report from the American Association for Vascular Surgery/Society for Vascular Surgery, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients With Peripheral Arterial Disease): endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation; National Heart, Lung, and Blood Institute; Society for Vascular Nursing; TransAtlantic Inter-Society Consensus; and Vascular Disease Foundation. Circulation. Mar 21 2006;113(11):e463-654.

backBack to Blog Home