Esophageal and Tracheal Compression of Huge Right Subclavian Artery Aneurysm Secondary to Aortic Coarctation
Article Outline
Right subclavian artery aneurysm due to coarctation of the aorta was diagnosed in a 33-year-old female patient who presented with dysphagia and dysphonia. Aortic coarctation and right subclavian artery aneurysm that compressed the trachea and the esophagus were successfully reconstructed with staged operations.
Keywords: Aortic coarctation, Right subclavian artery aneurysm, Aorta
Introduction
The right subclavian artery is an unusual location for aneurysms and an association with a coarctation of the aorta is even less frequent. We present an unusual huge right subclavian artery aneurysm secondary to an aortic coarctation resulting in serious compression on the esophagus and the trachea.
Case
A 33 years old female patient was hospitalized with three years history of pulsatile mass at the right side of her neck, shortness of breath, dysphagia, and dysphonia.
Her physical examination was normal except for the pulsatile mass (Fig. 1A) which was 15
×20cm in diameter and localized at the right side of her neck. The femoral pulses were decreased as compared with the radial pulses. Her blood pressure was 184/70mmHg in the right arm, 166/65 in the left arm. An ejection systolic murmur was audible over the precordium and radiated to the neck. The chest roentgenogram showed widened upper mediastinum and increased cardiothoracic ratio. Electrocardiogram displayed sinus rhythm and left ventricular hypertrophy.
Fig. 1
(A) Preoperative appearance of the mass located at the right side of the neck. (B) Angiography showing an aneurysmal dilatation of the proximal right subclavian artery (15
×20cm in diameter). (C) Angiography which shows the coarctation of the descending aorta.
Angiography demonstrated aortic coarctation distal to the left subclavian artery and an aneurysm formation beyond the origin of the right subclavian artery showing an extra-thoracic expansion (Fig. 1B and C).
Elective staged operations were planed for the surgical management. The first operation was aimed to relieve the coarctation in the descending aorta and was performed via a left thoracotomy. Heavy calcifications were found over the aortic wall, over the coarctation area and left subclavian artery so an extra-anatomic bypass was performed between the aortic arch and descending aorta by using a Dacron tube graft. The planned second stage operation was performed one month later than the first. The aorta arch and its branches were exposed through a median sternotomy. A huge right subclavian artery aneurysm causing esophageal and tracheal compression was dissected proximally and distally and controlled with vascular tapes (Fig. 2A). Compression of the esophagus and trachea was relieved by partial resection of aneurysmal sac. The aneurysmatic area of the subclavian artery was reconstructed by inlay 6mm Dacron tube graft (Fig. 2B). Postoperative recovery was uneventful.
Fig. 2
(A) Operative appearance of 15
×20cm in diameter right subclavian artery aneurysm. (B) Final appearance of the Dacron graft (6mm) interposed right subclavian artery.
Discussion
True subclavian artery aneurysms are rare, and most are due to atherosclerosis. Occurrence of the subclavian aneurysms in patients with coarctation of the aorta is well known. Other etiological factors in the pathogenesis of the true aneurysms include thoracic outlet obstruction, mycotic aneurysm and Ehler-Danlos syndrome.1
Aneurysms that appear distal to the coarctation are secondary to the turbulated flow in the region of the coarctation. Berry aneurysms are present in 10% of patients with coarctation and are related both to high pressure of the vascular tree above the coarctation and to congenital defects of vascular tree.2 In our case, formation mechanism of true right subclavian artery aneurysm may be explained with the sheer stress of rapid high pressure pulsatile flow into the subclavian artery caused by the aortic coarctation.
The common complications of subclavian artery aneurysms include compression, thrombosis, distal embolization and rupture.3, 4 Compression or acute expansion of subclavian artery aneurysms can produce symptoms such as, neck or shoulder pain. Subclavian aneurysms can cause respiratory problems due to tracheal compression; dysphagia due to esophageal compression and hoarseness as a result of the compression of the right recurrent laryngeal nerve. Horner's syndrome due to compression of the stellate ganglion; as well as sensory and motor signs due to brachial plexus compression has been described as well. Our patient presented with dysphagia and dysphonia as a result of the compression by he aneurysm.
Preoperative duplex ultrasonography and angiography are mandatory for planning the surgical treatment of an extrathoracic subclavian artery aneurysms. Other imaging modalities including CT or MRI may be necessary in cases with intrathoracic aneurysms.
Thrombosis, antegrade and retrograde emboli can complicate the subclavian artery aneurysm with the danger of cerebral infarcts and limb ischemia.5 Rupture is also a dangerous complication of this condition.
The surgical approach to subclavian artery aneurysms is dependent on the aneurysm's location. Median sternotomy is the preferred approach for right sided subclavian artery aneurysms whereas aneurysms of the left subclavian artery are best managed through a left thoracotomy.6 We preferred a left thoracotomy for the repair of the aortic coarctation and then a median sternotomy for the right subclavian aneurysm repair. There is a controversy about the proper timing of the surgical treatment of an unruptured branch aneurysms of aorta or an aortic coarctation. The risk of rupture also exits after surgical repair of aortic coarctation, in the absence of hypertension.7 Our review of the literature revealed no specific suggestion or evidence for the best timing of unruptured subclavian aneurysms together with coarctation of the aorta. Therefore we preferred to lower the proximal systemic blood pressure by repairing the coarctation site as the first stage. We felt this would make the second stage safer especially by reducing the risk of surgical bleeding and complications related to hypertension.
Endovascular procedures for the treatment of subclavian artery aneurysms should be considered as an alternative.8 In this case, an open repair was chosen because of the compressive symptoms and huge diameter of the aneurysm.
Aneurysms of the subclavian artery are an uncommon form of peripheral arterial aneurysms. Despite their infrequent occurrence, surgical treatment is mandatory because of the potential risk of rupture, thrombosis, embolization or compressive symptoms.
References
- . Subclavian-axillary artery aneurysms. Surgery. 1981;90:757–763
- . Coarctation of the aorta associated with aneurysm of the left subclavian artery. Br J Radiol. 2004;77:335–337
- . Diagnosis and treatment subclavian artery aneurysms. Eur J Vasc Surg. 1990;4:271–274
- . Left subclavian artery aneurysm rupture in association with aortic coarctation. Cardiovasc Intervent Radiol. 2006;29(4):717–719
- . Aneurysms of the subclavian artery. J Cardiovasc Surg. 1979;20:159–164
- . Subclavian artery aneurysms. Asian J Surg. 2003;26(1):7–11
- . Single-stage repair of adult aortic coarctation and concomitant cardiovascular pathologies: a new alternative surgical approach. J Cardiothorac Surg. 2006;(1):18
- . Combined open and endovascular treatment of a right subclavian artery aneurysm: a case report. J Vasc Surg. 2005;42(6):1206–1209
PII: S1533-3167(06)00090-2
doi:10.1016/j.ejvsextra.2006.10.006
© 2006 Elsevier Ltd. All rights reserved.
Refers to article:
- Esophageal and Tracheal Compression of Huge Right Subclavian Artery Aneurysm Secondary to Aortic Coarctation , 30 December 2006
