Upper-Extremity Arterial Occlusive Disease


Background

Arterial occlusive disease of the upper extremity may represent either local or systemic disease. The pattern of arterial disease varies according to etiology.

Diseases that affect the brachiocephalic vessels include atherosclerosis, arteritis, congenital anomalies, trauma, and fibromuscular dysplasia. In the United States, atherosclerosis is the most common cause of subclavian artery stenosis. Outside of the United States, Takayasu arteritis is more common. The axillary and brachial arteries are common sites of injury. One third of peripheral emboli lodge in the upper extremity, producing acute arterial occlusion. Radiation therapy of the chest or breast may induce subclavian artery disease.

Symptomatic upper-extremity arterial occlusive disease is uncommon because of the abundant collateral network and the infrequency of atherosclerosis in the upper extremity. Patients who present with upper-extremity ischemia range from young adults with nonatherosclerotic causes to elderly patients with atherosclerosis.

Anatomy

The right subclavian artery (see the image below) originates from the innominate artery. Rarely, its origin is distal to that of the left subclavian artery, passing behind the esophagus and producing dysphagia lusoria (ie, difficulty swallowing). An aberrant right subclavian artery is also prone to aneurysm degeneration (ie, Kommerell diverticulum).

Anatomic drawing of subclavian and brachial arteriAnatomic drawing of subclavian and brachial arteries.

The vertebral artery is the first branch of the subclavian artery and a major collateral for proximal subclavian artery stenosis (retrograde vertebral artery blood flow). The distal vertebral artery also provides blood flow to the anterior spinal artery.

The internal mammary artery (IMA) is the second branch of the subclavian artery and is used for coronary artery bypass grafting (CABG). Occasionally, progressive subclavian stenosis produces angina in patients who have undergone CABG.

The brachial artery branches at the elbow into the ulnar, radial, and interosseous arteries. Rarely, the ulnar and radial arteries arise from the axillary or subclavian arteries.

The ulnar and radial arteries connect in the hand to form the superficial and deep palmar arches. Palmar arch anatomy varies. In most patients, the ulnar artery is the dominant blood supply of the hand.

Pathophysiology

Vasculitis, fibromuscular dysplasia, and atherosclerosis produce symptoms related to progressive narrowing of the arterial lumen. A diameter reduction of 50% or a cross-sectional area reduction of 70% represents a hemodynamically significant lesion. These lesions produce a pressure drop across the stenotic area. The distal arterial bed is supplied by collateral blood vessels. Symptoms include exercise-induced fatigue as the demand for blood exceeds the supply.

In patients with acute arterial occlusions, collateral blood vessels have not formed, and perfusion drops rapidly below a critical threshold level, which results in persistent pain and tissue necrosis. Limb pressure is generally less than 30 mm Hg. Doppler tones cannot be heard in the digital vessels.

The pathophysiology of Raynaud syndrome is unknown. Precapillary smooth muscle cells constrict in an abnormal response to cold stimulation or emotional stress. [1Sympathetic nervous system adrenoreceptor function and number are believed to be altered. The distinction between Raynaud disease and Raynaud phenomenon is arbitrary and is best made by dividing patients into those with normal digital arteries (Raynaud disease) and those with obstructed arteries (Raynaud phenomenon). The two are easily distinguished with noninvasive blood flow testing (see Procedures).

Etiology

The etiology of upper-extremity occlusive disease includes the following:

  • Large-vessel occlusion (eg, subclavian, brachial, or forearm arteries)
  • Atherosclerosis
  • Trauma (eg, thoracic outlet syndrome, penetrating, [2blunt, or iatrogenic)
  • Arteritis (eg, Takayasu arteritis or giant cell arteritis)
  • Irradiation
  • Embolic (eg, cardiac or thoracic outlet in origin, including bacterial endocarditis, microemboli from ascending aorta, or paradoxical emboli)
  • Digital artery occlusion (see the image below)
  • Connective-tissue disease - SclerodermaCREST (chondrocalcinosis, Raynaud phenomenon, esophageal motility disorder, sclerodactyly, and telangiectasia) syndrome; and mixed connective-tissue disease
  • Buerger disease
  • Hypersensitivity angitis
  • Hematologic - Hypercoagulable states, hyperviscosity, or malignancy
  • Traumatic - Occupational (eg, hypothenar hammer syndrome or vibratory tools), iatrogenic, or recreational (baseball palmar artery injuries)
  • Infection - From injection of drugs or from arterial procedures
  • Flow phenomenon - Vascular steal related to dialysis access graft or fistula placement
Digital ischemia in patient with long-standing diaDigital ischemia in patient with long-standing diabetes mellitus who is on long-term dialysis.

Epidemiology

Brachial artery occlusion occurs in 0.9-4% of cardiac catheterizations. The brachial artery is also the most commonly injured artery in civilian trauma (30% of all arterial injuries). Digital gangrene is a frequent manifestation of connective-tissue disease or a hypercoagulable state. Thromboangiitis obliterans (Buerger disease) manifests with multiple digital artery occlusions caused by heavy smoking and is rare. Many patients with upper-extremity arterial disease have associated Raynaud syndrome or significant cold sensitivity.

Prognosis

Carotid-subclavian bypass yields 86-100% 5-year patency. Subclavian transposition yields 95-100% 5-year patency. Upper-extremity bypass yields 52% 5-year patency. Arterial reconstruction for thoracic outlet yields 90% 5-year patency.

Between 0% and 25% of patients with Raynaud disease with negative serology findings develop a connective-tissue disease, and 11-60% of patients with Raynaud disease with positive serology findings develop a connective-tissue disease.

Soga et al reported perioperative and long-term outcomes of endovascular therapy in 553 patients with upper-extremity arterial disease at 37 Japanese cardiovascular centers (mean follow-up, 39 ± 24 months). [3 The procedural success rate was 96.8%, the perioperative complication rate was 9.2%, and the incidence of stroke was 1.8%; 30-day mortality was 0.7%. Primary patency estimates were 90.6 ± 1.3% at 1 year, 83.4 ± 1.8% at 3 years, and 80.5 ± 2.2% at 5 years. Overall survival rates were 94.6 ± 1.0% at 1 year, 86.8 ± 1.7% at 3 years, and 79.0 ± 2.4% at 5 years.

In a study of 108 patients with critical hand ischemia owing to below-the-elbow atherosclerotic occlusive disease, Cheun et al compared three management approaches: no revascularization (n = 53), endovascular revascularization (n = 34), and open revascularization by bypass (n = 21). [4 All underwent catheter-based angiography.

In the no-intervention group, 26 patients required no intervention beyond wound care, 10 had an interval palmar sympathectomy, and 17 underwent either a phalanx or digital amputation. [4In the endovascular group, the procedure was technically successful for 29 of the 34 patients; two of the remaining five subsequently underwent bypass, one had a focal endarterectomy and patch angioplasty, and one was treated conservatively. In the bypass group, 11 patients underwent open or endovascular intervention to maintain patency of the bypass, and there were nine phalanx or digital amputations.



History

The patient’s history may include the following:

  • Arm fatigue upon exercise (ie, subclavian artery occlusion)
  • Vertebrobasilar insufficiency (ie, subclavian steal)
  • Rest pain that involves hand and digits
  • Digital gangrene
  • Raynaud syndrome (eg, color changes—white, blue, red or white, red, blue)
  • Smoking history
  • Occupational and recreational history (eg, baseball pitcher, tennis player, handballer, or carpenter)
  • Drug ergots (peripheral vasoconstrictors used in the treatment of shock [eg, dopamine and adrenaline])

Physical Examination

The results of physical examination may include the following:

  • Fever (if an associated vasculitis is present)
  • Unequal arm pressures (difference >20 mm Hg)
  • Supraclavicular or infraclavicular bruit
  • Adson maneuver (loss of radial pulse upon abduction and external rotation of the upper extremity)
  • Supraclavicular pulsatile mass (associated with a subclavian aneurysm or cervical rib)
  • Palpation of pulses (axillary, brachial, radial, or ulnar)
  • Digital gangrene
  • Color and capillary refill of the digits
  • A positive Allen test result

An abnormal Allen test result demonstrates an incomplete palmar arch. In this test, the ulnar and radial arteries are occluded with the fist clenched. The hand is then opened, releasing one of the arterial occlusions (radial or ulnar); prompt capillary refill should result. The same maneuver should then be performed with the release of the other artery. If the palmar arch is not intact, the release of the affected artery produces a sluggish capillary refill.

Alternatively, a Doppler stethoscope is used to map these collateral flow patterns in the hand by manually occluding, one at a time, the radial and ulnar arteries.



Laboratory Studies

In patients with Raynaud syndrome who may have systemic vasculitis or underlying connective-tissue disease, the following tests should be obtained:

  • Erythrocyte sedimentation rate (ESR) - To detect systemic inflammation or vasculitis
  • Antinuclear antibodies (ANA) - To test for serology of systemic lupus erythematosus (SLE)
  • Rheumatoid factor (RF) - To test for serology of rheumatoid arthritis

In selected patients, obtain a hypercoagulability workup. Molecular tests of hypercoagulability include the following:

  • Factor V Leiden mutation
  • Prothrombin 20210 gene mutation
  • Methyl tetrahydrofolate reductase (MTHFR) (homozygote)
  • Factor V (heterozygote)
  • Antithrombin III deficiency
  • Protein C deficiency
  • Protein S deficiency
  • Dysfibrinogenemia
  • Antiphospholipid antibodies
  • Hyperhomocysteinemia
  • Elevated lipoprotein (a)
  • Platelets

Additional tests include the following:

  • Complete blood count (CBC) and platelet count
  • Urinalysis
  • In selected patients, cryoglobulins, cold agglutinins, and serum protein electrophoresis

Imaging Studies

Complete arteriography of both upper extremities is necessary to establish the diagnosis and plan effective treatment. The arteries to the upper extremity must be clearly visualized, beginning with the arch and extending to the digits (see the images below). Magnification produces detailed studies of the hand.

Arteriogram of aortic arch demonstrating (1) brachArteriogram of aortic arch demonstrating (1) brachiocephalic vessel, (2) right subclavian, (3) right carotid, (4) left carotid, and (5) left subclavian. These are normal findings.
Brachial segment demonstrating high takeoff of radBrachial segment demonstrating high takeoff of radial artery from mid brachial artery.
Forearm vessels in patient with distal embolizatioForearm vessels in patient with distal embolization, including (1) radial artery, (2) interosseous artery, and (3) ulnar artery. (Ulnar artery demonstrates distal occlusion.)
Distal ulnar artery occlusion and proximal radial Distal ulnar artery occlusion and proximal radial artery occlusion with obliteration of superficial palmar arch from distal embolization.
Digital subtraction angiogram demonstrating normalDigital subtraction angiogram demonstrating normal subclavian axillary brachial segment with arm at patient's side.
Angiogram of upper extremity. Top is in normal posAngiogram of upper extremity. Top is in normal position; bottom is in hyperabducted position (arrow indicates area of stenosis).

Intra-arterial vasodilation often provides a detailed anatomy of the hand. The arm should be placed in the abducted externally rotated position to determine arterial occlusion produced by thoracic outlet structures (see the image below).

Chest radiography and cervical spine views reveal a cervical rib or abnormality of the first rib in patients with thoracic outlet syndrome. Alternatively, computed tomography (CT) with three-dimensional reconstruction can be used.

Transesophageal echocardiography (TEE) is performed in patients with a peripheral embolus suspected of originating from a cardiac source. TEE can be used to assess plaque in the ascending aorta as a source of the emboli or to determine the presence of a right-to-left shunt through which paradoxical emboli might travel.

Hand radiographs reveal calcinosis and tuft resorption.

In a prospective pilot study, Sumpio et al evaluated the use of hyperspectral imaging (HSI), a technology that noninvasively measures oxygenated hemoglobin and deoxygenated hemoglobin concentrations in the skin, for demonstrating upper-extremity vascular dysfunction inpatients with peripheral artery disease (PAD) and coronary artery disease (CAD). [5The study results suggested that HSI may be able to detect PAD or CAD on the basis of remote systemic vascular dysfunction at sites, thereby enabling early screening and tracking of arterial disease before it becomes clinically advanced.

Indocyanine green fluorescent imaging has been described as a noninvasive means of characterizing and quantifying microcirculatory disorders in patients with peripheral arterial occlusive disease of the upper extremity. [6]

Procedures

Noninvasive laboratory studies include bilateral upper-extremity arm, forearm, and digital blood pressures.

Doppler arterial waveforms are taken at the subclavian, axillary, brachial, ulnar, and radial arteries and the palmar arch. A triphasic waveform (see the image below) denotes normal arterial blood flow. Duplex scanning with Doppler spectral analysis and B-mode ultrasound provides a detailed anatomy of the subclavian, axillary, and brachial arteries.

Normal results on right upper extremity Doppler exNormal results on right upper extremity Doppler examination demonstrate triphasic waveform and wrist/brachial index of 0.63. Left upper extremity demonstrates axillary, brachial, and palmar artery disease.

In a retrospective analysis that evaluated the sensitivity and specificity of laser Doppler flowmetry (LDF) measurements for digital obstructive arterial disease (DOAD) against the reference standard of angiography, Mahe et al found that LDF combined with thermal challenge was an accurate, safe, and noninvasive method of detecting DOAD. [7]

Photoplethysmography (PPG) is used to monitor arterial blood flow to the fingers during the Adson maneuver and provides objective evidence of arterial occlusion.

The cold stimulation test is painful and rarely needed. A baseline temperature is recorded with a small digital thermistor. The hand is immersed in ice water for 20 seconds. The time to return to baseline temperature is normally 15 minutes. In patients with vasospastic disease, the recovery time is prolonged.

Histologic Findings

In patients with clinical findings and angiography findings consistent with giant cell arteritis, obtaining a biopsy of the affected arteries is usually impossible without risking the destruction of collateral vessels around the occlusion. Because this disease can affect other beds, results from a temporal artery biopsy may be abnormal.


Approach Considerations

Indications for surgical interventions in patients with upper-extremity occlusive disease include the following:

  • Arm fatigue - Carotid-subclavian bypass (see the first image below), percutaneous transluminal angioplasty (PTLA), and stenting
  • Vertebrobasilar insufficiency - Carotid-subclavian bypass and possible vertebral artery transposition to carotid artery
  • Subclavian aneurysm and thoracic outlet injuries with distal embolization - Resection of subclavian artery aneurysm and venous bypass and rib resection with thoracic outlet (see the second image below)
  • Acute arterial occlusion - Embolectomy for embolus and repair for trauma (blunt or penetrating)
  • Chronic arterial occlusion with pain at rest, ulcer, or gangrene - Bypass using the autogenous vein for distal segments and prosthetic material for larger proximal segments, amputation (digital or forearm), and sympathectomy (controversial)
Carotid-subclavian bypass. Carotid-subclavian bypass.
Subclavian transposition. Subclavian transposition.

Few contraindications for surgical intervention exist in the presence of significant cerebrovascular symptoms or gangrene of the hand. Arterial reconstruction may not be feasible if too many of the outflow target arteries are destroyed. Asymptomatic subclavian artery stenosis, even with radiographic evidence of subclavian steal (retrograde vertebral flow), should not be treated. Severe coexisting life-threatening illness may prevent surgical intervention.​

Medical Therapy

Long-term warfarin anticoagulation is recommended in patients with peripheral emboli from a cardiac source. An international normalized ratio (INR) of 2-3 is recommended.

For emboli off the ascending aorta, aspirin or clopidogrel may be used. In rare cases, low-dose aspirin has been used with warfarin.

Nifedipine (10 mg PO q8hr) is used in patients with vasospastic disease of the hand. If this is not tolerated, prazosin at a low dosage may be tried. A third-line drug with some effectiveness is hydralazine.

Lifestyle changes are essential. Warm gloves must be worn, and the skin must be protected from drying and fissuring. Cold avoidance may require moving to a warm climate and avoidance of significantly chilled or air-conditioned environments. Avoidance of vibration trauma from work or hobbies may be necessary.

In patients with Takayasu arteritis or giant cell arteritisprednisone is the first-line agent. Immunosuppression with methotrexate or cyclophosphamide may be necessary.

Risk-factor modification and aspirin are essential for the treatment of atherosclerotic occlusion. Smoking cessation is mandatory, particularly in patients with Buerger syndrome. Total cholesterol levels should be reduced to below 200 mg/dL, and the low-density lipoprotein (LDL) levels should be 100 mg/dL or less.

Surgical Therapy

Surgical options include the following:

  • Vein or prosthetic bypass [8]
  • Percutaneous balloon angioplasty and stenting [9]
  • Resection of aneurysm
  • Removal of first rib or cervical rib
  • Cervical sympathectomy

PTLA, with or without stenting, is used to treat proximal subclavian stenosis. The indications for PTLA of subclavian artery stenosis include vertebrobasilar insufficiency with steal, angina with left internal mammary artery (LIMA) graft, and arm fatigue.

The role of a thoracic or digital artery sympathectomy is controversial in patients with digital gangrene. These patients usually have an underlying connective-tissue disease, such as scleroderma; calcinosis, cutis, Raynaud phenomenon, esophageal motility disorder, sclerodactyly, and telangiectasia (components of CREST); or systemic lupus erythematosus (SLE). Either thoracic or digital sympathectomy provides a transient 6-12 months of increased skin perfusion.

A study of patients undergoing transfemoral upper-extremity angiography for acute finger ischemia found that in those patients without tissue loss or gangrene at the time of presentation, catheter-directed thrombolysis was associated with a trend toward improved amputation-free survival, suggesting that this modality may widen the revascularization options in appropriately selected patients. [10 A study by Schrijver et al found catheter-directed thrombolysis to be effective in more than 60% of patients as first-line treatment of extensive acute upper-extremity ischemia. [11]

Preparation for surgery

Standard preanesthesia evaluation should include chest radiography (if the patient has chest symptoms), electrocardiography (ECG), cardiac evaluation (if cardiac history or examination findings are abnormal), a complete blood count (CBC), and a chemistry panel. Prophylactic antibiotics should be administered. Ultrasound mapping should be done to delineate available saphenous or other veins to be used for bypass.

Operative details

For carotid subclavian or carotid transposition, a low transverse cervical incision is used. Prosthetic bypass is preferred. Complications include lymphocele, Horner syndrome, and phrenic nerve injury.

Balloon angioplasty and stenting are performed via either a retrograde or an antegrade approach.

For subclavian artery aneurysm resection and removal of cervical rib for thoracic outlet, the incisions are supraclavicular and infraclavicular. Efforts must be made to avoid brachial plexus injury. Rib resection is facilitated after division of the artery. Management of distal emboli is difficult. Complications include lymphocele, Horner syndrome, and phrenic nerve injury.

For procedures involving the axillary artery, exposure is through a longitudinal incision; ulnar, median, and musculocutaneous nerve injuries are possible. The brachial artery is exposed through an S incision; median nerve injury is possible.

Embolectomy should be avoided over areas distended by the balloon catheter. Brachial and small axillary arteries may be patched.

Postoperative Care

Monitor distal circulation with frequent pulse examination, with or without Doppler pressures. Monitor for bleeding and hematoma formation. Document neurologic function by testing median, ulnar, and radial nerve function. Be aware that forearm compartment syndrome can occur. Monitor ECG to rule out perioperative myocardial infarction or ischemia.

Complications

Potential complications include the following:

  • Bleeding (1%)
  • Hematoma (1%)
  • Phrenic or recurrent nerve injury (2%)
  • Graft occlusion (1-2%)
  • Wound infection (1%)
  • Brachial plexus or peripheral nerve injury (1%)
  • Stroke (< 1%)
  • Death (< 1%)

Long-Term Monitoring

The patient is seen at 2 weeks for wound check, suture removal, or both. Repeat upper-extremity blood flow tests are performed every 3 months for the first year, then annually thereafter. Review the patient's control of risk factors, including smoking.


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