An acutely ischaemic hand in a young adult due to subclavian artery aneurysm (SAA) caused by a cervical rib: A case report
© Tam et al; licensee BioMed Central Ltd. 2008
Received: 10 July 2008
Accepted: 04 September 2008
Published: 04 September 2008
True subclavian artery aneurysms are relatively rare lesions. Thoracic outlet compression is responsible for 75% of aneurysms. They are formed as a result of compression by, for example a cervical rib.
We present a case of subclavian artery aneurysm secondary to a cervical rib in a 25-year-old young Asian adult, who presented with an acutely ischaemic upper limb. A Computed Tomography angiogram revealed a right sided cervical rib and sacular aneurysm in the mid-portion of the subclavian artery.
Although it is a rare condition, it is important to be aware especially in the young age group. Surgical management has very favourable outcomes in these patients.
An aneurysm of the subclavian artery is uncommon. In the younger age group the cause is usually due to thoracic outlet compression often due to an extraneous cervical rib. One such exceptional case of arterial thoracic outlet syndrome presenting in a young man is described below.
A, healthy 25 year old Asian male presented with a 3 day history of sudden onset worsening pain of the right forearm and hand. He was a non-smoker with no history of trauma and no past medical history of note. On examination, he had classical signs of acute limb ischaemia consisting of pallor, coldness with prolonged capillary refill of about 10 seconds and sensory and motor impairment. Pulsatile mass in the root of the right side of the neck with a bruit and flow murmur was also elicited. On hand held Doppler ultrasound of the right arm, a diminished ulnar artery signal and a monophasic radial artery signal were detected, along with a normal brachial artery signal. A clinical diagnosis of aneurysm of the subclavian artery was made with embolic occlusion of the brachial artery.
True subclavian artery aneurysms are relatively rare lesions, accounting for approximately 0.13% of all aneurysms [1, 2]. Atherosclerotic aneurysms are more commonly found in males over the age of 60 years [3, 4]. Thoracic outlet compression is responsible for 75% of aneurysms which arise from the distal part of the subclavian artery, also known as extrathoracic subclavian artery or subclavian-axillary artery aneurysms . They are formed as a result of compression by, for example a cervical rib, malalignment post-clavicular fracture or congenital bands on the artery as it passes through the interscalene triangle. This causes stenosis and angulation of the artery, which with time will lead to post-stenotic dilatations [4, 5]. However, these aneurysms are only found in 1.1% of patients with thoracic outlet syndrome (TOS) . Patients may present with symptoms of thromboembolism, such as digital ischaemia, Raynaud's phenomena, pulsatile masses in the supraclavicular fossa or axilla, brachial plexopathy or Horner's syndrome .
The remainder of the aneurysms arise from the proximal part of the subclavian artery, also known as intrathoracic or proximal subclavian artery aneurysms . They are mainly the result of atherosclerosis and are usually asymptomatic . However, symptoms of compression, including discomfort in the neck, dysphagia and dyspnoea have been reported. Other causes of subclavian artery aneurysms include trauma, iatrogenic; and rarely arteritis, cystic medial necrosis, congenital, syphilis and tuberculosis [4, 7].
Plain films and ultrasound scanning are used to identify bony abnormalities and confirm the presence of an aneurysm. However CT or magnetic resonance imaging angiography remain the investigations of choice [3, 4].
Open surgical repair is the standard management, even for asymptomatic subclavian artery aneurysms due to their tendency to increase in size or rupture . This involves resection of the aneurysm and reconstruction of the artery with or without graft insertion. Decompression of the TOS with resection of the cervical and/or 1st rib, anterior scalene muscle or constricting fibrous bands; or median sternotomy and lateral thoracotomy may be necessary for intrathoracic aneurysms [4, 7]. This depends on the cause and site of the aneurysm. Distal arterial occlusion secondary to emboli will warrant angioplasty or thromboembolectomy to restore patency of the vessels . Overall, surgical management has very favourable outcomes in these patients .
Cervical rib leading to subclavian artery aneurysms should always be included in the differential diagnosis of an acutely ischaemic hand. It is a rare event especially in the young adult. This report illustrates the importance and difficulty of correctly diagnosing a rare pathology that has a common presentation. It is important to recognise subclavian artery aneurysms secondary to cervical rib in patients with TOS as they can be safely managed preventing rupture and further thrombosis.
Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.
Vascular surgical secretary of RP for obtaining patient notes post-discharge.
- Pagni S, Denatale RW, Ferneini AM: Atherosclerotic aneurysm of the proximal subclavian artery: a case report. Am Surg. 1998, 64 (4): 323-327.PubMedGoogle Scholar
- Douglas DA, Adelman MA, Esposito R, Rockman C: Surgical repair of a left subclavian artery aneurysm causing stenosis of a left internal mammary graft: A case report. Vascular and endovascular surgery. 2005, 39 (3): 281-285. 10.1177/153857440503900310.View ArticlePubMedGoogle Scholar
- Rutherford RB: Vascular Surgery. 2005, America: Elsevier Saunders, 1552-1557. 6Google Scholar
- Hallett JW, Mills JL, Earnshaw J, Reekers JA: Comprehensive Vascular and Endovascular surgery. 2004, London: Mosby, 485-489.Google Scholar
- Engel A, Adler OB, Carmeli R: Subclavian artery aneurysm caused by cervical rib: a case report and review. Cardiovasc Intervent Radiol. 1989, 12: 92-94. 10.1007/BF02577396.View ArticlePubMedGoogle Scholar
- Utikal P, Bachleda P, Kocher M, Novotny J, Drac P: Aneurysm of the subclavian artery. Acta Univ Palacki Olomuc Fac. 1999, 142: 107-109.Google Scholar
- Leemput AV, Maleux G, Heye S, Nevelsteen A: Combined open and endovascular repair of a true right subclavian artery aneurysm without proximal neck. Interact CardioVasc Thorac Surg. 2007, 6: 406-408. 10.1510/icvts.2006.149088.View ArticlePubMedGoogle Scholar
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