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Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017
| Contributor Information
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Data in graph from Ramana RK et al.[2]
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Peripheral arterial disease (PAD) affects approximately 8.5 million Americans aged 40 years or older and is associated with significant morbidity and mortality.[1] Risk factors associated with PAD include smoking, diabetes, hypertension, hyperlipidemia, family history, male sex, race, obesity, and aging. Notably, smokers and patients with diabetes are at three- to fourfold higher risk for PAD as compared with the general population. Although hypercoagulable states can aggravate the symptoms of PAD, they are not a risk factor for the development of PAD.
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
What is the most common presenting symptom of PAD in the office setting?
Pain at rest
Claudication
Tissue loss
Poor wound healing
Image courtesy of Wikimedia Commons.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: B. Claudication.
Although most individuals with PAD are asymptomatic, the most common individual presenting symptom in the outpatient office setting is claudication,[1,3] a term denoting pain during exertion that is relieved with rest. Answers A, C, and D occur in more advanced PAD. The majority of patients with PAD have mild blockages in the arteries that do not impede blood flow to the legs and feet. This occurs with lactic acid buildup in active muscles and a switch to anaerobic metabolism as a consequence of lack of oxygen secondary to hemodynamically significant blockages in the arteries. As blockages of blood flow become more severe, less blood gets to the limb, and symptoms result. Severe blockages lead to even more severe signs and symptoms.
Table adapted from Fontaine R et al[4] and Rutherford RB et al.[5]
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Pain at rest, ulcers, and gangrene are ominous signs in PAD. Patients who have these symptoms require revascularization. Rest pain in vascular patients occurs when the amount of blood flowing to the extremity is so low that the tissues experience ischemic pain. Ulcers and wounds have a difficult time healing when the blood supply is inadequate. The healing process imposes increased demands for oxygen and nutrients, which, because of the upstream blockages in blood flow, cannot be met. Gangrene is the most severe form of PAD, in which tissue starts to die as a consequence of lack of blood flow.
The Fontaine and Rutherford systems (shown) are commonly used to classify PAD. In the Rutherford system, categories 4 through 6 are considered to warrant intervention.
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
A 62-year-old man presents with symptoms of severe claudication in his left lower extremity.
Which of the following findings is/are apparent on this patient's hand?
Pale skin
Muscle atrophy
Nicotine staining
Thickened nails
Shiny, tight skin
Hair loss
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: C. Nicotine staining.
Nicotine staining is visible at the tips of the first and third digits, as well as between the second and third digits. Smoking is one of the risk factors for developing PAD (see slide 1).[6] Although answers A, B, D, E, and F are also changes that are commonly seen in the legs and feet of individuals with advanced PAD, those findings are not apparent on this patient's hand.
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Which of the following bedside tests is most reliable for diagnosing PAD?
Pulse examination
Skin color
Skin temperature
Ankle-brachial index (ABI)
Images courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: D. Ankle-brachial index (ABI).
The ABI is a reliable way of determining whether a patient has significant PAD.[7] Skin color and temperature are often affected by the ambient temperature and by individual physiologic factors. The pulse examination is notoriously unreliable in diagnosing patients with PAD. It may be reliable if the pulse is palpated in the first few seconds of the examination, but it is not uncommon for struggling examiners to mistake the pulsations at their own fingertips for patients' pulses.
The ABI can be obtained by using a manual blood pressure (BP) cuff and a Doppler ultrasound device. The Doppler device is used to measure the occlusion pressure of the artery (systolic BP) at the level of the brachial artery in the arm and at the level of the ankle. The ratio of the ankle occlusion pressure to the brachial artery occlusion pressure is the ABI. A normal value for the ABI is 1.0; if the ABI is below 0.85, the patient has PAD.
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Which of the following diagnostic modalities should be used as a screening tool for evaluation of PAD?
Pulse volume recording (PVR) with ABI
Duplex ultrasonography (US) of the arteries
Computed tomography angiography (CTA)
Magnetic resonance angiography (MRA)
Diagnostic angiography
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: A. Pulse volume recording (PVR) with ABI.
PVR with ABI is an inexpensive, noninvasive, reliable, and safe method of screening patients for PAD.[8] PVR measures the volume changes that occur with flow into the leg and records these changes on a time graph. It is usually done in conjunction with an ABI. Multiple pressure cuffs are applied at the levels of the thigh, calf, ankle, and great toes. These are inflated to a nominal pressure (usually 40-60 mm Hg). The changes in volume in the leg translate to changes in pressure in the cuff bladder. These pressures changes are graphed with a transducer over time.
Of the other modalities, CTA and diagnostic angiography are the more reliable choices. CTA involves significant x-ray exposure and the use of larger volumes of intravenous (IV) contrast. Diagnostic angiography is invasive and requires arterial puncture and the use of IV contrast and x-rays; however, it remains the gold standard test for the purposes of diagnosis and intervention. MRA is generally not as reliable and tends to overestimate the level of stenosis. All of these other modalities also tend to be much more expensive than PVR with ABI.
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
A 68-year-old man with a history of smoking, hypertension, and type 1 diabetes for the past 10 years presents to the office with the foot lesions shown. The femoral and popliteal pulses are palpable, but the dorsalis pedis and posterior tibial pulses are not. An ABI of 0.9 is obtained at the bedside.
Given that the ABI is in the normal range, what is the most likely explanation for the tissue loss?
Trauma to the great toe
Embolization to the great toe
Pyoderma gangrenosum
Calcified arteries that are noncompressible and thus cause a false elevation of the ABI
Image courtesy of Medscape/W Michael Park, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
D. Calcified arteries that are noncompressible and thus cause a false elevation of the ABI.
Although trauma and embolization to the toe can give rise to similar lesions, the patient's history, coupled with the absence of pulses, suggests that he probably has calcifications in the walls of his vessels. These calcifications make it harder to compress the vessels and thereby cause systolic occlusion pressures to be falsely elevated. Typically, patients with diabetes or renal failure exhibit such calcifications in their blood vessels. The image shows the rocky plaque that is responsible for palpable pipestem posterior tibial arteries.
Images courtesy of Dreamstime (top) and Babak Abai, MD, and F Brian Boudi, MD (bottom).
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
A 76-year-old woman with hypertension and hyperlipidemia presents with claudication. The physical examination and bedside ABI testing lead to the determination that the patient has PAD.
Having PAD increases the risk of developing which of the following conditions?
Myocardial infarction (MI)
Stroke
Hypercoagulable state
Both A and B
Image courtesy of Wikimedia Commons.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: D. Both A and B.
Atherosclerosis usually is not confined to a single vessel bed. (Data in the image are from the AGATHA study.[9]) Often, it is a systemic process and affects the blood vessels supplying the legs, the brain, the heart, and other organs. Patients with a diagnosis of PAD therefore are at greater risk for both MI and stroke. This information should help clinicians screen for and aggressively treat the risk factors. In addition, antiplatelet agents have been beneficial in this patient population with regard to reducing stroke and MI rates.
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
A 71-year-old male smoker with a history of hypertension presents with disabling one-block claudication. He says that the pain is interfering with his life and normal activities; he can no longer walk anywhere outside, because he has to stop. He is not the type to sit at home and wants to be able to walk again.
What is the first-line treatment for this patient?
Medical therapy
Endovascular procedure
Open surgical procedure
Observation
Image courtesy of Medscape.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: A. Medical therapy.
The first-line treatment for claudication is medical therapy. Patients with claudication are not at risk for loss of a limb; in fact, only a minority of these patients progress to limb-threatening ischemia. Observation is not the correct answer, because ways of treating the symptoms medically are available. More aggressive therapies are offered to patients who have disabling claudication (eg, a patient who may lose his or her job because of claudication or one who will otherwise become completely sedentary) that cannot be satisfactorily treated by medical means.
Medical therapy includes modification of risk factors, including stopping smoking and controlling hypertension and hyperlipidemia. In patients with diabetes, good blood sugar control should be observed. Some physicians advocate statin therapy as well, even for patients with only marginally high lipid levels. Patients should also be taking an antiplatelet agent (aspirin or clopidogrel) and should be encouraged to improve their diet (eating more healthily and controlling portions). Walking exercises for 30 minutes a day, in which patients try to walk through the pain, have been effective in helping the muscle tolerate the low-oxygen environment and may as much as double the preexercise walking levels. In addition, cilostazol has been shown in randomized trials to double the walking distance without pain.[10]
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
The patient returns to the office in 3 months and complains of worsening claudication. He says that he has cut down on his smoking and has tried walking exercise and cilostazol without obtaining any relief. In addition, he has started taking a baby aspirin once a day.
What is the most appropriate next step in management?
Continued medical therapy
CTA of the abdomen and lower extremities
Angiography with potential intervention
Open surgery
Images courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: C. Angiography with potential intervention.
Failure of medical therapy in a patient with severe disabling claudication can be an indication for intervention. Although further studies can be obtained beyond the usual PVR with ABI, duplex US and CTA are purely diagnostic, whereas angiography offers the possibility of intervention (if indicated). Many interventional approaches to relieving arterial occlusion or stenosis are available, including angioplasty, stenting, and atherectomy.
In the slide, the left image shows an occluded right superficial femoral artery. The occlusion is traversed by using a wire to dissect through a subintimal plane. Once reentry on the other side of the occlusion is confirmed, a stent can be deployed. The middle image shows balloon angioplasty and deployment of a stent. The right image shows the final result, with inline flow to the right lower extremity reestablished.
Image courtesy of Babak Abai, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
The Trans-Atlantic Intersociety Consensus (TASC) system, established in 2000 and subsequently updated in 2007 (TASC II), classifies the severity of an arterial lesion on the basis of its angiographic appearance. This system was developed in order to guide management of PAD.
Which TASC category does the angiogram in the slide illustrate?
TASC A
TASC B
TASC C
TASC D
Images courtesy of Babak Abai, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: A. TASC A.
TASC A lesions are focal stenoses that can be treated by endovascular means. TASC D lesions (right) are long occlusions that are not optimally treated with endovascular techniques and are best treated by means of a bypass procedure. With TASC B lesions (left) and TASC C lesions (middle), the choice of therapy is left to the clinician's judgment, depending on the patient's condition, age, and operative risk. The general recommendation, however, is that for TASC B lesions, endovascular therapy should take precedence, and for TASC C lesions, an open procedure should be considered.
Images courtesy of Blueringmedia | Dreamstime.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Which of the following technologies is not currently used to treat PAD?
Atherectomy
Radiofrequency ablation (RFA)
Drug-eluting balloon angioplasty
Drug-eluting stent placement
Covered stent placement
Cryoplasty
Image courtesy Frédérik Astier / Science Source.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: B. Radiofrequency ablation (RFA).
Of the technologies listed, RFA is the only one that is not currently in use for the treatment of PAD. It is, however, used to treat superficial venous reflux by ablating the superficial malfunctioning veins (great saphenous vein [GSV], small saphenous vein [SSV], and perforator veins).
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
A 69-year-old man with a history of type 1 diabetes, hypertension, and hyperlipidemia presents to the hospital with wounds on the right foot. He also has a history of fourth-digit amputation on the right foot. The workup included an angiogram that demonstrated a long lesion of the right superficial femoral artery and right popliteal artery and reconstitution of a right anterior tibial artery proximally flowing to the foot. A bypass procedure is planned.
Before the bypass operation, what additional study or studies should be done?
Cardiac evaluation
Radiography of the right foot
Vein mapping of the GSVs
Typing and cross-matching of blood for the operating room (OR)
All of the above
Images courtesy of Babak Abai, MD (top left and right, bottom left), and Medscape (bottom right).
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: E. All of the above.
A bypass operation is the gold standard for treatment of long occlusions of the vessels. It is performed to salvage a limb with very poor blood flow. Before this patient goes to the OR, a cardiac evaluation is mandatory to confirm that he can tolerate the operation. Open revascularizations tend to be physiologically stressful, and one of the risks for such operations is MI. In addition, radiography of the foot can rule out deep soft-tissue infections and osteomyelitis. Preoperative vein mapping, which involves examining the vessel with duplex US, can be helpful in determining if a vein is usable for bypass.
Which of the following is the best conduit for a lower-extremity bypass operation?
Autogenous vein
Cadaveric vein
Extruded polytetrafluoroethylene (ePTFE) graft
Dacron graft
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: A. Autogenous vein.
The patient's own GSV is the best option. The inner lining of a vein has antithrombotic properties that make it ideal for this use. In bypass procedures, autologous vein has been found to yield higher patencies than any other conduit. Unfortunately, the GSV is not always usable: It may be too small or scarred, or it may already have been harvested for a coronary artery bypass procedure. Cadaveric vein is treated and decellularized and thus lacks the antithrombotic properties of native vein; it is also expensive and has no advantage over prosthetic conduits in terms of patency. Dacron, being soft and lacking external support, is rarely used to revascularize limbs, though it is used for repair of the aorta and iliac arteries. ePTFE is the second choice for this application. Current ePTFE grafts are coated with heparin on the inner surface to improve patency, and they have external rings that help prevent the soft graft from collapsing. Various adjunctive techniques can be used to improve ePTFE graft patency in the short-to-moderate term, including the Miller cuff, the Taylor patch, and anticoagulation.
In this patient, an attempt was made to harvest the GSV, but the vessel was sclerotic and unusable (see the inadequate segment on the left side of the slide). Preoperative vein mapping, though often helpful, is not foolproof—as in this case, where the vein appeared potentially adequate on US but proved to be inadequate when harvested.
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Because a suitable vein segment is not available in the case under discussion, an ePTFE graft is chosen instead. The image in the slide shows the graft after it has been tunneled into the patient's leg.
Images courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
The images in the slide show the proximal anastomosis in the operation performed to treat this same patient. The ePTFE graft is cut to shape, and the artery is opened (left). The graft is then sewn onto the artery (right). The distal end of the graft is sewn into the distal vessel.
Image courtesy of Medscape/Sam Shlomo Spaeth.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
When medical therapy, endovascular therapy, and surgical therapy for PAD have all failed, what is the final therapeutic option?
Sympathectomy
Amputation
Hyperbaric oxygen therapy
None of the above
Image courtesy of Babak Abai, MD, and F Brian Boudi, MD.
Peripheral Arterial Disease: Getting the Patient Back in Circulation
Babak Abai, MD; F Brian Boudi, MD | June 22, 2017 | Contributor Information
Answer: B. Amputation.
Once revascularization fails, the best option remaining is amputation. Studies show that in a minority of patients who suffer from superficial skin wounds, sympathectomy will be beneficial in helping heal these wounds; however, the effects of sympathectomy on blood flow are, at best, modest.[11] Hyperbaric oxygen therapy has also been used successfully in a minority of patients with nonhealing wounds and suboptimal blood flow.[12] Nevertheless, when blood flow is extremely poor and there are no options for revascularization, amputation remains the only viable choice.
Hidden Heart Disease: 19 Dermatologic Clues You Should Know
Cardiac diseases often have cutaneous manifestations. Are you able to correctly diagnose these patients based on their dermatologic presentations?Slideshows, June 2017
Peripheral vascular disease (PVD) is a nearly pandemic condition that has the potential to cause loss of limb or even loss of life. PVD manifests as insufficient tissue perfusion initiated by existing atherosclerosis acutely compounded by either emboli or thrombi.Diseases/Conditions, December 2016
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Contributor Information
Authors
Babak Abai, MD, FACS
Assistant Professor of Surgery
Program Director, Vascular Surgery Fellowship
Division of Vascular and Endovascular Surgery
Thomas Jefferson University
Philadelphia, PA
Disclosure: Babak Abai, MD, FACS, has disclosed no relevant financial disclosures.
F Brian Boudi, MD, FACP
Staff Physician, Phoenix VA Health Care System
Clinical Clerkship/Elective Director, ER
Clinical Associate Professor of Medicine
University of Arizona, College of Medicine
Adjunct Associate Professor, Mid-Western University School of Medicine
Regional Faculty, American Heart Association
Disclosure: F Brian Boudi, MD, FACP, has disclosed no relevant financial disclosures.
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Fowkes FG et al; AGATHA Investigators. Ankle-brachial index and extent of atherothrombosis in 8891 patients with or at risk of vascular disease: results of the international AGATHA study. Eur Heart J. 2006 Aug;27(15):1861-7. [PMID: 16820367]
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