팔로사징을가진소아에서좌경부대동맥궁과 연관이상소견. Left cervical aortic arch and Associated Abnormalities in a child with Tetralogy of Fallot. Abstract *

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1 부산대병원학술지통권제 31 호, 2012 팔로사징을가진소아에서좌경부대동맥궁과 연관이상소견 양산부산대학교병원영상의학과 김용우 Left cervical aortic arch and Associated Abnormalities in a child with Tetralogy of Fallot Yong-Woo Kim Department of Radiology, Pusan National University Yangsan Hospital Abstract * 경부대동맥궁은대동맥궁이쇄골상부에위치하는드문선천성기형이다. 경부대동맥궁은보통증상없는독립된기형으로발생하나, 다른심혈관계이상들과동반해서발생하기도한다. 대동맥류와협착이흔히같이발생하지만, 본증례처럼대동맥궁변이가동반되는경우는매우드물다. 저자는팔로사징의심도자술중에진단된환아에서, 전산화단층촬영혈관조영술로확인된, 좌측쇄골하동맥기시부동맥류와이중기시부를가진추골동맥을동반한좌경부대동맥궁 1례를경험하였기에보고한다. * 본연구는 2010 년도양산부산대학교병원임상연구비지원으로이루어졌음

2 김용우 중심단어 : 대동맥궁, 팔로사징, 대동맥류, 추골동맥중복, 기형중복기원, 전산화단층촬영대동맥기형 Key words: Barin metastases, Lung cancer, Radiation therapy Introduction Cervical aortic arch (CAA) is a rare congenital anomaly in which the aortic arch is situated on cranial position above the clavicle. 1,2. The position of the arch varies from slightly superior to normal to very high in the neck, lying on either side of the trachea. 1,3 CAA usually occurs as an isolated anomaly without symptom, but in some cases it may be associated with other cardiac and aortic abnormalities. 1-4 Whereas aortic aneurysm and coarctation are well-documented associations, CAA accompanied by aortic arch variation is very rare. 1-4 Presenting features vary from a pulsatile mass in the supraclavicular fossa to symptoms simulating a respiratory tract infection. 5 Hence its diagnosis by non-invasive means is desirable. We report a case of left CAA with left subclavian artery aneurysm and aortic arch variation that was accompanied by duplicate origin of left vertebral artery in a patient with tetralogy of Fallot (TOF). To our best knowledge, this is the first report of CAA complicated by aortic arch variation and duplicate origin of left vertebral artery. Case Report A 2-year-old girl was admitted to our hospital for further evaluation of cardiac murmur known at birth. On physical examination, she had a cyanosis of lip and systolic murmur best heard on the left midsternal border (grade lll or lv). The plain chest radiography showed normal shaped heart but the aortic shadow was not well demarcated and the widening of superior mediastinum was noted (Fig 1a). Echocardiography demonstrated a large perimenbranous VSD (about 14mm), pulmonary stenosis, and the overriding of aorta. Patient was diagnosed as TOF. Cardiac catheterization was done for the evaluation of TOF and associated cardiac abnormalities. The angiogram following contrast injection in the left ventricle through VSD showed that the aortic arch was left sided and tortuously elongated to the level of the 7 th cervical spine. It also showed the descending

3 팔로사징을가진환아에서좌경부대동맥궁과연관이상소견 thoracic aorta to be lef tsided (Fig1b). For further evaluation of aortic arch and its branching pattern, the CT angiography of chest (Volumezoom,Erlangen,Siemens) was performed. The CT angiography confirmed anomalous course of the aortic arch above left clavicle, normal vessel dimensions, and absence of concomitant coarctation or aneurysm. CT angiography provided additional information about aortic branch vessels. The left branch arteries of aortic arch were hypoplastic and left subclavian and vertebral artery anomalously originated from the upper portion of the descending thoracic aorta. Left subclavian artery was accompanied by small aneurysm at the origin (Fig2). Left vertebral artery had duplicated origin from the left subclavian artery and the aortic arch distal to the left subclavian artery. The two segments joined each other at the level of C6 vertebra and ascend into the C5 transverse foramen (Fig 3). For the evaluation of associated chromosome 22q11 deletion syndrome, a chromosome examination was conducted by the fluorescent in situ hybridization (FISH) method. Cytogenetic analysis revealed no evidence of the chromosome 22q11 deletion. She underwent surgery for repair of TOF but anomalous aortic arch was remained without surgical treatment. Discussion Cervical aortic arch is a rare congenital anomaly in which the ascending aorta extends in such a way that the aortic arch is situated cranial to its usual position. 5 The position of the arch varies from slightly superior to normal to very high in the neck, lying on either side of the trachea. 1,3 Nonetheless the diagnosis of this anomaly should be made when the aortic arch is supraclavicular. 5,6 The prevalence of CAA is less than a case every 10,000 live births. 7 Many patients with CAA are asymptomatic, while others present with respiratory problems, dysphagia, pain around the neck and chest, and ischemic cerebrovascular attack. 6 Left CAA is often asymptomatic as opposed to right CAA, which is usually associated with dysphagia and respiratory distress due to the compression by the vascular rings. The mechanism of development of an aortic arch anomaly is explained by the hypothetical double aortic arch system. 8 The persistence of the left fourth branchial arch and the regression of the right fourth branchial arch produce a normal left aortic arch between the fifth and seventh embryonic weeks. Various theories have been proposed to

4 김용우 explain the CAA. 4,9,10 There are three major theories explaining the development of the CAA. Persistence of the second or third branchial arch combined with the resorption of the fourth branchial arch is one theory. Lack of caudal migration of an otherwise normal fourth arch is the second theory. The third theory explains the high position as the result of fusion between the third and fourth arch combined with failure to descend into the thorax. Recent work suggests that the CAA is often associated with chromosomal abnormality (deletions in chromosome 22q11 region) Hence these lesions could be included in the spectrum of defects known as catch 22. This syndrome is characterized by cardiac defects, abnormal facies, thymic hypoplasia, cleft palate, hypocalcemia, and a deletion in choromosome 22. But in our case, there is no evidence of chromosome 22q11 deletion in the cytogenetic analysis. Many patients with CAA are asymptomatic, but others present with respiratory problems due to compression of the trachea or esophagus by a vascular ring. In about 30 % of the cases of CAA, cardiac anomalies are also present, such as TOF, VSD, or double-outlet right ventricle. 14 Our patient had TOF with the cervical aortic arch. CAA usually presents between the ages of 20 and 40 and has an equal sex distribution except when associated with aneurysm formation, which occurs in approximately 20% of patients, only female patients with CAA have developed aneurysm. The aneurysm formation may occur secondary to left CAA in 20% of cases and particularly in female patient. Most aneurysms are in the transverse aortic arch, which is the location least affected by other types of aortic aneurysm. So female patients with CAA, such as our case, should take follow-up imaging annually to identify the possible formation of aneurysm. CAA commonly occurs as an isolated anomaly andis usually silent. Presenting features vary from a pulsatile swelling in the supraclavicular fossa to symptoms simulating a respiratory tract infection. Infant and children may present with features caused by associated congenital heart condition. The predominant congenital heart anomaly associated with right CAA is ventricular septal defect.other cardiac abnormalities include double outlet right ventricle, tricuspid atresia and atrial septal defect. Left CAA has been associated with patent ductus arteriosus, TOF, and pseudotruncus. 1-3 The present case is left CAA with TOF

5 팔로사징을가진환아에서좌경부대동맥궁과연관이상소견 as associated cardiac abnormality. It also has been known that TOF is associated with aortic arch anomalies such as a right aortic arch, an aberrant subclavian artery, an elongated ascending aorta or a high aortic arch. 15. But in that report, patients with high aortic arch almost had a right aortic arch and there was no case in which the apex of the arch was in the cervical position. 15 In our survey, the only one case has been reported about cervical aortic arch associated with TOF. 16 The patient was an adult (38-year-old) with right cervical aortic arch and he had a chromosome 22 abnormality. 16. But in this case, the patient was very young (2-year-old) and she was not associated with chromosome 22 abnormality. CAAs were classified into five morphologic types based on the side of the descending aorta and the branching pattern by Haughton et al. 17, although some cases were unclassifiable. Type D in the Haughton classification is the most frequent type of CAA. Type D CAA manifests ipsilateral descending aorta with normal sequence of the major three arteries. 10 Our case has left cervical aortic arch with left sided descending aorta, close to Haughton type D. But the branching pattern is different with type D. In our case, left subclavian artery was origin from descending aorta and left vertebral artery had anomalous origin distal to left subclavian artery on 3D-volume rendering images. In our case, the review of the acquired axial data of CTA showed duplicate origin of left vertebral artery from the aortic arch and left subclavian artery. The term duplication is applied to a vertebral artery that has two origins with a variable level of fusion in the neck. Duplication is very rare, with few reports in the literature. Vertebral artery duplication is reported to be more common on the left. 18 The duplicated segments usually fuse at C4-6. The vertebral artery develops from net-like and longitudinal anastomoses between the cervical intersegmental arteries at the early embryonic stage. Normally the cervical intersegmental arteries regress, except for the sixth vessel. The sixth cervical intersegmental artery becomes the proximal portion of the subclavian artery and the point of origin of the vertebral artery. Duplication of the vertebral arteries arises as a result of failure of involution of intersegmental arteries. This persists as an additional origin to the vertebral artery, along with the sixth artery (schema)

6 김용우 To our knowledge, only several cases demonstrating a duplicate origin of the left vertebral artery from the aortic arch and left subclavian artery have been reported But all cases had anomalous aortic arch origin between the left common carotid and the left subclavian arteries. In our case, the anomalous origin of left vertebral artery arises directly from the aorta distal to the left subclavian artery. Our case would be explained as follows: the branch arising from the left subclavian artery would represent the normal persistence of the sixth intersegmental artery, with the anomalous origin from the aortic arch representing a persistence of the seventh intersegmental artery. 18,20 With the advent of multislice helical CT scanner, CTA can provide anatomic and pathologic information of aortic arch and its branches. While three-dimensional reconstructions enable visualization of the entire course of the aortic arch and its branch arteries, review of the acquired axial data is important to fully understand the vertebral artery configuration and identify abnormalities in the adjacent tissues. In our case, there was focal aneurysm in the origin of the left subclavian artery. Although various congenital anomalies and/or cardiovascular abnormalities are occasionally complicated in CAA, there has been only one case report of CAA with branch artery aneurysm. The hemodynamic alteration, such as tortuous kinking, and abnormal structural integrity of branch artery may contribute to this rare branch aneurysm. In conclusion, the CAA associated with TOF, branch artery aneurysm, and duplicate origin of left vertebral artery is the first case. We could successfully demonstrate the location of the arch, its branching pattern, and associated complication using CT angiography. We considered that CT angiography was suitable for evaluating congenital anomaly of the aortic arch and related vessels without invasive procedure and for accurate follow-up monitoring the aneurysm formation which may occur secondary to left CAA (20% of cases) or abrupt aortic rupture, particularly in female patient. We recommend the patient with CAA and associated anomalies under a program of annual surveillance to identify the possible formation of aneurysm. References 1. Kumar S, Mandalam KR, Unni M, Roy S, Gupta AK, Rao VR. Left cervical arch and associated abnormalities. Cardiovasc Intervent

7 팔로사징을가진환아에서좌경부대동맥궁과연관이상소견 Radiol. 1989;12: Tsukamoto O, Seto S, Moriya M, Yano K. Left cervical aortic arch associated with aortic aneurysm, aortic coarctation, and branch artery aneurysm--a case report and review. Angiology. 2003;54: Moncada R, Shannon M, Miller R, White H, Friedman J, Shuford WH. The cervical aortic arch. Am J Roentgenol Radium Ther Nucl Med. 1975;125: DuBrow IW, Burman SO, Elias DO, Hastreiter AR, Pietras RJ. Aortic arch in the neck. J Thorac Cardiovasc Surg. 1974;68: Kumar S, Bajaj R, Gujral R. Case report: MR angiography of cervical aortic arch. Clin Radiol. 1997;52: Doorenbos BM, Mooyaart EL, Hoorntje JC. MR diagnosis of a right cervical aortic arch. J Comput Assist Tomogr. 1991;15: Samánek M, Slavík Z, Zborilová B, Hrobonová V, Vorísková M, Skovránek J. Prevalence, treatment, and outcome of heart disease in live-born children: a prospective analysis of 91,823 live-born children. Pediatr Cardiol. 1989;10: Stewart JR, Kincaid OW, Edwards JE. An atlas of vascular rings and related malformations of the aortic arch system. Charles C Thomas, Springfield, IL, 1964, 8-13, Hirao K, Miyazaki A, Noguchi M, Shibata R, Hayashi K. The cervical aortic arch with aneurysm formation. J Comput Assist Tomogr. 1999;23: Ogawa S, Ozaki Y, Sumi Y, Kyogoku S, Maehara T. MR angiography of left-sided cervical aortic arch with aneurysm formation. Magn Reson Imaging. 2002;20: Ikonomidis JS, Robbins RC. Cervical aortic arch with pseudocoarctation: presentation with spontaneous rupture. Ann Thorac Surg 1999;67: McElhinney DB, Clark BJ 3rd, Weinberg PM, Kenton ML, McDonald-McGinn D, Driscoll DA, et al. Association of chromosome 22q11 deletion with isolated anomalies of aortic arch laterality and branching. J Am Coll Cardiol. 2001;37: Pearson GD, Kan JS, Neill CA, Midgley FM, Gardner TJ, Hougen TJ. Cervical aortic arch with aneurysm formation. Am J Cardiol. 1997;79: Kazuma N, Murakami M, Suzuki Y, Umezu R, Murata M. Cervical aortic arch associated with 22q11.2 deletion. Pediatr Cardiol. 1997;18:

8 김용우 15. Nakajima Y, Nishibatake M, Ikeda K, Momma K, Takao A, Terai M. Abnormal development of fourth aortic arch derivatives in the pathogenesis of tetralogy of Fallot. Pediatr Cardiol. 1990;11: Emmel M, Schmidt B, Schickendantz S. Double aortic arch in a patient with Fallot's tetralogy. Cardiol Young. 2005;15: Haughton VM, Fellows KE, Rosenbaum AE. The cervical aortic arches. Radiology 1975;114: Goddard AJ, Annesley-Williams D, Guthrie JA, Weston M. Duplication of the vertebral artery: report of two cases and review of the literature. Neuroradiology 2001;43: Padget DH. The development of cranial arteries in the human embryo. Contrib Embryol 1948;32: Suzuki S, Kuwabara Y, Hatano R, Iwai T. Duplicate origin of left vertebral artery. Neuroradiology 1978;15: Eisenberg RA, Vines FS, Taylor SB. Bifid origin of the left vertebral artery. Radiology 1986;159: Hashimoto H, Ohnishi H, Yuasa T, Kawaguchi S. Duplicate origin of the vertebral artery: report of two cases. Neuroradiology 29:

9 팔로사징을가진환아에서좌경부대동맥궁과연관이상소견 Figure legands Fig. 1. On chest radiography (1a), heart seemed normal. But the aortic shadow was not well demarcated and mild superior mediastinal widening was noted (arrows). Cardiac angiography (1b) in the left ventricle through VSD, showed that the aortic arch was elongated to the level of the seventh cervical spine and was tortuous with kinking (arrows)

10 김용우 Fig. 2. The MIP and 3D images of chest CT angiography (A-C) showed a left side cervical aortic arch with ipsilateral descending aorta. The right brachiocephalic artery and its branches had normal size (thin arrows in 2A-B), but the left side branching arteries were hypoplastic. And left common carotid artery (thick arrows in 2A-B) directly originated from the top of aortic arch. The left subclavian artery is arising from descending aorta and associated with small aneurysm at the origin (thin arrow in 2C ). The left vertebral artery originated from descending aorta, just below left subclavian artery (thick arrow in 2C)

11 팔로사징을가진환아에서좌경부대동맥궁과연관이상소견 Fig. 3. The sequential axial images of chest CT angiography (a-d) showed a left sided aortic arch with ipsilateral descending aorta. Left common carotid artery (long arrow in 3A) directly originated from the ascending aorta. Left subclavian artery (thin double arrow in 3B & 3C) is arising from descending aorta and it is associated with small aneurysm (thin arrow, 3C). Left verterbral artery has duplicated origin with one segment arising from the aortic arch (arrowhead in 3A-3D) and the other off the left subclavian artery (short arrow, 3A & 3B). Two duplicated segments join into a single vessel at the level of C-6 and enter into the foramen transversarium of the fifth cervical vertebra

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