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Chapter 10
Duplex assessment of upper extremity arterial disease
133
INTRODUCTION
In contrast to lower limb arteries, atherosclerotic disease in the upper extremities is rare and accounts for approximately 5% of all extremity disease (Abou- Zamzam et al 2000). The most commonly affected sites are the subclavian (SA) and axillary arteries. The disorder is sometimes associated with extracranial carotid artery disease. Radiotherapy in this region, resulting in fibrosis and scarring, can also cause damage to the SA and axillary arteries. Compression of the SA in the area of the thoracic outlet, known as thoracic outlet syndrome (TOS), can produce significant upper limb symptoms.
Acute obstruction of the axillary or brachial arter- ies may also occur due to embolization from the heart or SA aneurysms. In this situation, duplex scanning is useful for demonstrating the length and position of the occlusion. Microvascular disorders, such as Raynaud’s phenomenon, can produce significant symptoms in the hands, which may be confused with atherosclerotic disease.
ANATOMY OF THE UPPER EXTREMITY ARTERIES
The anatomy of the upper extremity arteries is illustrated in Figures 10.1 and 10.2. The left SA divides directly from the aortic arch, but the right SA originates from the innominate or brachio- cephalic artery. The thoracic outlet is the point where the SA, subclavian vein and brachial nerve plexus exit the chest. The SA runs between the anterior and middle scalene muscles and passes
CHAPTER CONTENTS
Introduction 133
Anatomy of the upper extremity arteries 133 Symptoms and treatment of upper limb
arterial disease 135
Practical considerations for duplex assessment
of upper extremity arterial disease 135 Scanning techniques 136
Subclavian and axillary arteries 136 Brachial artery 137
Radial and ulnar arteries 137
Palmar arch and digital arteries 138 Commonly encountered problems 138
Ultrasound appearance 138
Normal appearance 138
Abnormal appearance 138
Thoracic outlet syndrome (TOS) 139
Maneuvers for assessing TOS 140
Duplex assessment of TOS 141
Aneurysms 142
Ultrasound assessment of hemodialysis
access grafts and arteriovenous
fistulas (AVF) 142
Other disorders of the upper extremity
circulation 143 Reporting 143