CHRONIC ISCHEMIA OF THE LOWER EXTREMITY
Selections from the University of California, Davis, Health System’s 26th Annual Postgraduate Course in General
Surgery
| NONATHEROSCLEROTIC CAUSES OF CLAUDICATION—Gregory L. Moneta, MD, Professor and Chief, Division of
Vascular Surgery, Oregon Health and Science University, Portland
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Nonarterial Claudication
| Neurogenic claudication: central stenosis of spinal cord (usually from osteoarthritis of lumbar spine or disc disease) and
peripheral nerve entrapment; characterized by shooting pain in dermatomal distribution; pain—less reproducible than
atherogenic claudication; requires more time to resolve (≤30 min); occurs with standing; no change in ankle-brachial index
(ABI); risk factors—more common in men (bilateral 8 times more common; unilateral 3 times more common); age
>50 yr; history of back pain; gait or posture abnormalities; physiology—need 2 areas of narrowing in spinal cord combined
with venous engorgement of vein plexus in spinal cord or nerve root; treatment—surgery for decompression of
spinal cord indicated for patients with severe symptoms; nerve stimulators indicated for patients with minor symptoms
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| Venous claudication: incomplete recanalization of iliofemoral deep venous thrombosis (DVT) and increased venous pressure
with exercise; patient describes bursting sensation in legs with exercise; venous physiology—slower and less complete
filling of veins; slower emptying when tourniquet released; air plethysmography—patients do not eject as much
blood from veins with exercise and have more reflux as measured by venous filling index; treatment—bypass can be preformed
but has poor long-term patency (2-yr patency 60%); stents used more frequently (patency rates slightly better than
surgery), but treatment avoided if possible
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| Exertional compartment syndrome: calf hypertrophy leading to impairment of venous outflow and calf swelling; improves
with cessation of activity and leg elevation; diagnostic criteria—pressure >25 mm Hg for 10 min after cessation
of activity (normal compartment pressure <15 mm Hg)
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Nonatherosclerotic Arterial Claudication
| Popliteal entrapment: results from anomalous relationship between gastrocnemius muscle and popliteal artery; predominantly
affects men; often bilateral; patients often present with acute ischemia from arterial occlusion; physiology—most
common form when artery deviates around medial head of gastrocnemius muscle; second most common form when medial
head of gastrocnemius muscle inserts between artery and vein; diagnosis—most commonly made using magnetic
resonance imaging (MRI)
|
| Cystic adventitial disease: predominantly affects men; age of onset usually <40 yr; likely caused by mucin-secreting cells
derived from synovial cells of adjacent joint; diagnosis—use noninvasive forms, reserving angiography for patients in
whom intervention indicated; artery has scalloped appearance on ultrasound and MRI; treatment—speaker uses resection
of artery and interposition grafting
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| Persistent sciatic artery: developmental abnormality; sciatic artery may replace or coexist with femoral artery; claudication
more likely when persistent sciatic artery has replaced femoral artery, because connection between sciatic artery and
popliteal artery tends to be atretic or prone to atherosclerotic involvement; patients usually <50 yr of age; treatment—
standard bypass techniques; where sciatic artery coexists with femoral artery, patients often have aneurysmal degeneration
and may require treatment
|
| Fibromuscular disease: can occur in iliac and forearm arteries; predominantly affects women; tends to affect external iliac
arteries; consists of narrowing of vessels and claudication-type symptoms; source of embolization
|
| Buerger’s disease: thrombotic occlusion of small vessels, usually in smokers; affects upper and lower extremities; results
in instep claudication; diagnostic criteria—onset <45 yr of age; tobacco use; no evidence of arterial disease proximal to
popliteal or brachial arteries; objective evidence of distal occlusive disease; absence of proximal embolic source, trauma,
autoimmune disease, hypercoagulable states, atherosclerosis, and atherosclerotic risk factors; treatment—bypass procedures
ineffective, especially in patients who continue to smoke
|
| MEDICAL MANAGEMENT OF CLAUDICATION—David L. Dawson, MD, Associate Professor of Surgery, University
of California, Davis, School of Medicine
|
| Peripheral arterial disease Awareness, Risk, and Treatment: New Resources for Survival (PARTNERS) trial:
ABI ≤0.9 used as specific for diagnosis of peripheral artery disease (PAD); PAD commonly detected in at-risk patients,
eg, those with history of smoking, diabetes; patients with PAD have impaired quality of life and physical functioning;
50% of PAD patients lacked diagnosis of PAD before PARTNERS trial
|
| Peripheral arterial outcomes: ≈75% of patients with intermittent claudication have stable symptoms at 5 yr; <25% have
worsening claudication or undergo bypass surgery; major amputation rate 4% to 8%; nonfatal cardiovascular events occur
in ≈20% of patients (5-yr mortality 20% to 30%)
|
| Atherosclerosis risk factors: blood pressure goal of <140/90 mm Hg; all classes of antihypertensives can be used; ACE
inhibitors may have benefit; glycemic goal of HbA1c <7.0% for patients with diabetes
|
| Antiplatelet therapy: 25% reduction in risk for serious vascular events in at-risk patients; baby or regular aspirin qd effective
|
| Clopidogrel versus Aspirin in Patients at Risk of Ischemic Events (CAPRIE) trial: aspirin and clopidogrel effective
at preventing myocardial infarction (MI), stroke, and cardiovascular death; for patients with PAD, clopidogrel achieved
greater benefit than aspirin
|
| Lipid lowering: reduces cardiovascular mortality risk; National Cholesterol Education Program (NCEP) guidelines—for
patients with PAD, target low-density lipoprotein (LDL) level <100 mg/dL; reduce triglycerides; elevate high-density lipoprotein
(HDL) cholesterol; initiate pharmacologic therapy in patients with LDL-cholesterol >130 mg/dL; consider therapy for patients
with LDL-cholesterol 100 to 130 mg/dL; revised guidelines—LDL-cholesterol goal of <70 mg/dL for patients at very
high risk
|
| Exercise training: increases walking capacity and overall functional status; effective programs are supervised, use walking,
and last 3 to 6 mo; exercise needs to be continued or benefit lost; TransAtlantic Inter-Society Consensus (TASC)
document—“program of exercise therapy, preferably supervised, always should be considered as part of initial treatment
for patients with intermittent claudication”
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| Pharmaceutical therapy: pentoxifylline (Trental)—approved by Food and Drug Administration (FDA); methylxanthine
derivative; effective in small studies; variable response; current practice guidelines do not stress use; cilostazol
(Pletal)—FDA-approved; improves walking; affects platelets, smooth muscle, and lipids; study—patients randomized to
cilostazol 100 or 50 mg or placebo bid; dose-dependent response for pain-free and maximal walking distance (patients
walked further with higher doses); patients taking placebo also improved over time; study—patients randomized to cilostazol
100 mg bid, pentoxifylline 400 mg tid, or placebo; cilostazol improved pain-free and maximal walking distance;
pentoxifylline did not improve maximal walking distance significantly, compared to placebo; withdrawal—loss of efficacy
when drug withdrawn; maintenance therapy required; quality of life—cilostazol associated with significant differences
in bodily pain, physical and role-physical function, and physical summary
|
| ENDOVASCULAR TREATMENT OF SUPERFICIAL FEMORAL ARTERY OCCLUSIVE DISEASE—William C. Pevec,
MD, Professor of Surgery, University of California, Davis, School of Medicine
|
| Hypothetical case: 58-yr-old senior executive who quit smoking 2 yr ago after smoking 2 packs per day for 40 yr; complains
of pain in left calf after walking 200 yd; no improvement after 6 mo of treadmill exercise and cilostazol;
evaluation—arteriography showed normal proximal superficial femoral artery (SFA) and proximal popliteal artery, focal
stenosis in popliteal artery above knee, and normal run-off arteries
|
| Consensus paper: meta-analysis of treatment of femoropopliteal artery stenoses and occlusions; for angioplasty, 3-yr primary
patency 50%; for stents, 3-yr primary patency 58% to 60%; data suggest stents offer no improvement over angioplasty
for lesions in femoropopliteal segment
|
| Study: patients randomized to selective or primary stents for SFA lesions <7 cm; 1-yr patency same for both groups; 17 patients
(15%) in selective group received stent because of suboptimal angioplasty results; 1-yr, 2-yr, and 4-yr vascular
event-free survival same for both groups; data suggest primary stenting not indicated for short lesions
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| SFA occlusion: consensus paper—angioplasty for stenosis in femoropopliteal segment had 5-yr patency of 68%; for total
occlusion, 5-yr patency 35%
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| Stent-grafts: in small studies of stent-graft use in SFA, 1-yr patency 60% to 80% (2-yr patency similar); study—patients
randomized to stent-graft or angioplasty for total occlusion of femoropopliteal arteries; at 2 mo, stent-graft primary patency
87%, compared to 25% for angioplasty; ideal indications for stent-graft included segment >1 cm proximal and
distal to target lesion with no obstruction, no lesions in popliteal artery, 1 patent run-off artery, and no severe calcifications;
for ideal patients treated with stent-grafts, 3-yr primary patency 70% and 3-yr secondary patency 83%
|
 | Stent-graft manufacturer data: 4-yr primary patency—vein graft 75%; synthetic graft 50%; stent-graft had same 2-yr patency
as synthetic graft; stents and angioplasty inferior techniques; long lesions (>10 cm)—stent-graft performed better
(at least at 2 yr) than bare stent
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| Study: for 42 stent-grafts, 4-yr primary patency 70%
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| AXILLOFEMORAL AND INFRAINGUINAL BYPASS: TECHNICAL PEARLs—Dr. Moneta
|
Axillofemoral Bypass
| Grafts: 8-mm ring polytetrafluoroethylene (PTFE) grafts and PTFE sutures used; ring reinforcement protects against compression
and kinking; if anastomosis of PTFE graft to axillary artery too tight or lateral, graft may tear out of axillary artery;
placing anastomosis medial to pectoralis minor muscle reduces likelihood of graft pulling out of artery; if anastomosis too
tight, it may pull axillary artery down over time, compressing artery, and can lead to occlusion of vessel and embolization
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| Bypass tunnel: tunneler allows single pass of axillofemoral component from groin to axillary artery without need for
counterincision; tunnel passes anterior to anterior superior iliac spine in cases not performed for infection, underneath
pectoralis minor and major muscles, and up into axillary incision
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| Graft configuration: femoral-femoral bypass placed first; axillofemoral component anastomosed to hood of femoral-femoral
bypass in right groin
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| Patent SFA and axillofemoral bypass: patent SFA not required; study—no difference in 5-yr primary patency for axillofemoral
grafts, regardless of whether SFA occluded; patency and limb salvage results similar for axillofemoral and
aortofemoral grafts
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| Graft occlusion: study—of 335 patients who received axillofemoral grafts, 10% underwent reoperation for graft occlusion
due to thrombosis; of patients who underwent reoperation, 43% had single reoperation procedure (4 patients accounted
for 29% of reoperation procedures); graft replacement (with or without thrombectomy) achieves better long-term
patency than thrombectomy alone
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Reverse Vein Grafting
| Indications: preferred technique for infrainguinal bypass; in situ bypass grafting applicable only to first-time operations
(intact saphenous vein required)
|
| Bypass procedure: use distal origins of bypass whenever possible to use shortest amount of vein; soft proximal arteries
important, soft distal arteries less so; try to incorporate side branch of vein in proximal anastomosis to avoid tendency to
kink at heel of graft
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| Bypass tunnel: use anatomic tunnels for most operations and subcutaneous tunnels when graft at high risk for revision
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| Separation of prosthetic and vein grafts: better results achieved when vein graft has native origin, compared to prosthetic
origin; occlusion of prosthetic graft takes down infrainguinal graft if it originated from prosthetic graft; if vein graft
originates distal to prosthetic graft off native vessel, vein graft stays patent 80% of time after prosthetic graft occlusion
|
| Alternative veins: be willing to use alternative veins and venovenostomies; alternative vein bypass has lower primary patency
than saphenous vein bypass; with close follow-up and appropriate revision, alternative vein bypass has same patency
as ipsilateral greater saphenous and contralateral greater saphenous vein tibial bypass
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| AMPUTATION OF THE LOWER EXTREMITY—James E. Holcroft, MD, Professor of Surgery, University of California,
Davis, School of Medicine
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| Team approach: activate team before amputation; reassure patient that they will maintain independence; begin aggressive
rehabilitation immediately after operation
|
| Amputation options: compatible with good quality of life—any toe amputation distal to metatarsophalangeal joint; ray
amputation of single minor toe; transmetatarsal amputation of all toes; below knee amputation; not compatible with good
quality of life—ray amputation of great toe or 2 minor toes; forefoot amputations; above knee amputation
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| Ray amputation of great toe: ray amputation of great toe contraindicated in most cases because it results in deformed foot,
uneven pressure-bearing surface, skin breakdown, and ulceration; transmetatarsal amputation avoids these problems;
exception—ray amputation of great toe indicated if plantar surface of foot has gangrenous areas that will not support
transmetatarsal amputation
|
| Lisfranc, Chopart, and Syme amputations: disadvantages—usually produce mobile pressure-bearing surface on bottom
of foot, ie, heel pad on bottom of bone slides, leading to skin breakdown and ulceration; prosthesis clumsy;
advantages—allow growth of tibia in children; can go short distances without protection or need for prosthesis or
crutches
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| Through knee and above knee amputations: disadvantages—older patients unlikely to achieve independent ambulation,
leading to loss of hope; need to achieve flow in profunda
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Educational Objectives
| The goal of this program is to educate the listener about chronic ischemia of the lower extremity. After hearing and assimilating
this program, the clinician will be better able to:
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| 1. Review nonatherosclerotic causes of claudication.
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| 2. Manage claudication with medical therapies.
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| 3. Use endovascular approaches for the treatment of superficial femoral artery occlusive disease.
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| 4. Relate technical pearls on axillofemoral and infrainguinal bypass operations.
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| 5. Select the appropriate procedure for a lower extremity amputation.
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Discussed on This Program
Aspirin (acetylsalicylic acid; ASA) [several trade names]
Cilostazol [Pletal]
Clopidogrel bisulfate [Plavix]
Pentoxifylline [Trental]
Suggested Reading
Becquemin JP et al: Systematic versus selective stent placement after superficial femoral artery balloon angioplasty: a
multicenter prospective randomized study. J Vasc Surg 37(3):487, 2003; Dawson DL et al: A comparison of cilostazol
and pentoxifylline for treating intermittent claudication. Am J Med 109(7):523, 2000; Delis KT: The case for intermittent
pneumatic compression of the lower extremity as a novel treatment in arterial claudication. Perspect Vasc Surg Endovasc
Ther 17(1):29, 2005; Delis KT et al: Venous claudication in iliofemoral thrombosis: long-term effects on venous hemodynamics,
clinical status, and quality of life. Ann Surg 239(1):118, 2004; Dormandy JA, Rutherford RB: Management of
peripheral arterial disease (PAD). TASC Working Group. TransAtlantic Inter-Society Consensus (TASC). J Vasc Surg
31(1 Pt 2):S1, 2000; Fox CJ et al: Cystic adventitial disease of the popliteal artery. J Vasc Surg 39(6):1351, 2004;
Grundy SM et al; Coordinating Committee of the National Cholesterol Education Program: Implications of recent
clinical trials for the National Cholesterol Education Program Adult Treatment Panel III Guidelines. J Am Coll Cardiol
44(3):720, 2004; Henry MF et al: Popliteal Artery Entrapment Syndrome. Curr Treat Options Cardiovasc Med 6(2):113,
2004; Hirsch AT, Hiatt WR; PARTNERS Steering Committee: PAD awareness, risk, and treatment: new resources for
survival--the USA PARTNERS program. Vasc Med 6(3 Suppl):9, 2001; Hirsch AT et al: Peripheral arterial disease detection,
awareness, and treatment in primary care. JAMA 286(11):1317, 2001; Klevsgard R et al: A 1-year follow-up quality
of life study after hemodynamically successful or unsuccessful surgical revascularization of lower limb ischemia. J Vasc
Surg 33(1):114, 2001; Ohta T et al: Clinical and social consequences of Buerger disease. J Vasc Surg 39(1):176, 2004;
Pursell R et al: Spontaneous and permanent resolution of cystic adventitial disease of the popliteal artery. J R Soc Med
97(2):77, 2004; Rybarczyk B et al: Diversity in adjustment to a leg amputation: case illustrations of common themes. Disabil
Rehabil 26(14-15):944, 2004; Saxon RR et al: Long-term results of ePTFE stent-graft versus angioplasty in the femoropopliteal
artery: single center experience from a prospective, randomized trial. J Vasc Interv Radiol 14(3):303, 2003;
Sheahan MG et al: Lower extremity minor amputations: the roles of diabetes mellitus and timing of revascularization. J
Vasc Surg 42(3):476, 2005; Turnipseed WD: Atypical claudication associated with overuse injury in patients with chronic
compartment, functional entrapment, and medial tibial stress syndromes. Cardiovasc Surg 11(5):421, 2003; Turnipseed
WD: Diagnosis and management of chronic compartment syndrome. Surgery 132(4):613, 2002; Wallace GF, Stapleton
JJ: Transmetatarsal amputations. Clin Podiatr Med Surg 22(3):365, 2005.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue, the following
has been reported: Dr. Dawson is on the Speaker’s Bureau for Otsuka America Pharmaceutical, Inc.
Drs. Moneta, Dawson, Pevec, and Holcroft were recorded September 18, 2004, at General Surgery 2004—26th Annual
Postgraduate Course sponsored by the University of California, Davis, Health System and held in Olympic Valley, California.
The Audio-Digest Foundation thanks the speakers and the University of California, Davis, Health System for their
cooperation in the production of this program.
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