Overview

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.

Problems

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.

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 syndromeor significant cold sensitivity.

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, ^[1] blunt, 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)
• Fibromuscular dysplasia
• Digital artery occlusion (see the image below)
• Connective-tissue disease – Scleroderma; CREST (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

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.^[2] The sympathetic 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 Diagnostic Procedures).

Presentation

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])

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.

Indications

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)

Contraindications

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.