Br Heart J 1989;61:540-5

Anomalous subaortic position of the brachiocephalic(innominate) vein: a review of published reports andreport of three new cases

LEON M GERLIS, SIEW YEN HO

From the Department of Paediatrics, National Heart and Lung Institute, London

SUMMARY Anomalous courses of the left innominate vein have rarely been described inanatomical specimens. Investigative techniques such as angiography and echocardiography havebrought to light more instances of this anomaly. Three more cases identified by anatomical studyare described. Earlier cases were reviewed to assess the type of associated cardiac malformations.Clinically, the abnormality is regarded as benign. When it is recognised during investigation itshould alert the clinician to the possibility ofassociated malformations. Features commonly seen intetralogy of Fallot-right aortic arch, ventricular septal defect, and right ventricular outflowobstruction-were common in patients with anomalous subaortic innominate veins.

The left brachiocephalic (or innominate) vein ex-tends from the junction of the left internal jugularand left subclavian veins to the junction of the rightbrachiocephalic (or innominate) vein and the (right)superior caval vein. The normal course is obliquelydownwards and to the right, passing in front of theleft subclavian, left common carotid, and brachio-cephalic arteries, beneath the aortic arch.' Veryrarely, this vein (or its analogue) follows ananomalous course, passing from left to right belowthe arch of the aorta, to enter the (right) superiorcaval vein below the orifice of the azygos vein.Kershner first described this anomaly a hundredyears ago,2 and we are aware of at least another 21cases (table). We report three further cases.Although the malformation in itself seems to be of

no functional importance, we assessed its importancein terms of associated conditions and its possiblerelevance to subsequent operations.

Case reports

CASE 1This girl died when she was 5 years 11 months oldafter cerebral ischaemia after attempted surgicalcorrection of tetralogy of Fallot. Postmortemexamination of the heart showed usual (solitus) atrial

Requests for reprints to Dr Leon M Gerlis, Department ofPaediatrics, National Heart and Lung Institute, Dovehouse Street,London SW3 6LY.

Accepted for publication 20 January 1989

arrangement with concordant atrioventricular andventriculoarterial connections, infundibular andvalvar pulmonary stenosis, subaortic ventricularseptal defect, and several large aortopulmonaryanastomoses. There was a right sided aortic arch.The site of the arterial duct was not apparent. Thelarge left brachiocephalic vein passed behind theascending aorta and below the aortic arch beforeentering the superior caval vein (vena cava), belowthe level ofthe azygos vein and just above its junctionwith the right atrium (fig 1).

CASE 2This male infant died of complex cardiac malforma-tion at one day. There was the usual (solitus) atrialarrangement with concordant atrioventricular con-nection and double outlet right ventricle with adextroposed aortic orifice overriding a peri-membranous ventricular septal defect. There ap-peared to be an ectopic portion of atrioventricularvalve, complete with leaflet tissue, tendinous cords,and papillary muscles, situated between thetrabecular and infundibular components of the rightventricle. The unguarded pulmonary artery orificeshowed no trace of arterial valve leaflets. The arterialduct was short and widely patent. The aortic arch wasleft sided and had normal branches. The left internaljugular vein continued into a descending vein, whichpassed under the aortic arch from left to right,anterior to the arterial duct and between the arch andthe pulmonary trunk. It then ran behind the ascend-ing aorta to enter the lower portion of the superior

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Anomalous subaortic position of the brachiocephalic (innominate) vein

Table Reported cases of subaortic left brachiocephalic vein

Reference Relation to Aortic Other cardiovascularCase Authors Year No Age Sex Diagnosis arterial duct arch malformations

1 Kerschner 1888 2 ? (child) ? Necropsy ? L None2 Daser 1902 6 68 yr M Necropsy Anterior L None3 Ghon 1908 7 41/2 mnth F Necropsy Posterior R Absent L 4th arch,

isolated L subclavianartery

4 Nutzel 1914 8 74 yr M Necropsy ? L Right superiorpulmonary vein tosuperior caval vein

5 Martin 1931 9 17 yr M Necropsy Anterior R Fallot6 Walter 1931 10 19 yr M Necropsy Anterior L Subthyroid venous

anastomosis7 Adachi 1933 11 20 yr M Necropsy Anterior L None8 Adachi 1933 11 41 yr M Necropsy Posterior L None9 Friedman 1945 12 66 yr M Necropsy Anterior L L jugular vein anomaly10 Roberts et al 1951 1 7 yr F Angio Subpulmon art L None11 Sherman 1963 4 ? ? Necropsy Anterior L Pulnonary atresia VSD12 Sherman 1963 4 ? ? Necropsy Anterior L Pulmonary atresia VSD13 Yoshida et al 1975 13 68 yr M Necropsy Anterior L None14 Kitamura et al 1981 14 69 yr M Necropsy Anterior L None15 Cloez et al 1982 15 1 /2yr M Echo and angio ? L Fallot16 Smallhom et al 1985 5 ? ? Echo ? R17 Smallhornet al 1985 5 ? ? Echo ? R Rlh It18 Smallhorn et al 1985 5 ? ? Echo ? R anomalies frequent.19 Smallhorn et al 1985 5 ? ? Echo ? R Intra cardiac anomalies20 Smallhom et al 1985 5 ? Echo ? R in six ( VSDs).21 Smallhorn et al 1985 5 i ? Echo ? R Central pulnonary22 Smallhom et al 1985 5 ? ? Echo ? L arteries absent in one

23 Gerlis et al 1988 - 5 yr 11 mnth F Necropsy No duct R Fallot24 Gerlis et al 1988 - 1 day M Necropsy Anterior L Complex25 Gerlis et al 1988 - 7 wk F Necropsy No duct R Common arterial

trunk

Angio, angiography; echo, echocardiography; subpulmon art, subpulmonary artery; VSD, ventricular septal defect.

Fig 1 Photograph and diagram of case I showing theanomalous left brachiocephalic vein (ALBV) running behindthe ascending aorta (Ao) and below the right aortic arch(RAA) before entering the superior caval vein (SCV).

caval vein between the entry of the azygos vein andthe junction with the right atrium. Because thespecimen was damaged it was impossible to ascertainthe connection between this anomalous vein and theleft subclavian vein. There was, however, no

evidence of any other route of venous drainage fromthe left arm (fig 2).

Fig 2 Photograph and diagram of case 2 showing theanomalous left brachiocephalic vein (ALBV) passing belowthe aorta (Ao). AD, arterial duct; PT, pulmonary trunk.

CASE 3This seven week old female infant died afterattempted surgical correction of a commnon arterialtrunk. There was the usual atrial arrangement withconcordant atrioventricular connection and a sub-truncal ventricular septal defect with an overridingquadricuspid truncal valve. The pulmonary arteriesoriginally had separate orifices from the posterior

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aspect of the common arterial trunk. The aortic archwas right sided and its branches were a mirror imageof the normal arrangement. No arterial duct orligament was present.The left sided brachiocephalic vein descended to

the left ofthe ascending aorta and then passed behindit to the right side, below the aortic arch, to open intothe left medial aspect of the superior caval veinbetween the entry ofthe azygos vein and the junctionwith the right atrium (fig 3).

.......~~~~ ~ ~

-1_ X L{~~~~~~RAA LBV

Fig 3 Photograph and diagram of case 3 showing the

anomalous left brachiocephalic vein (ALBV) passing below

the right aortic arch (RAA) before entering the superiorcaval vein (SCV). The photograph shows the vessels after

surgical correction of the comnwn arterial trunk (CAT),with the insertion of a pulmonary conduit (PC). The

diagram shows the original state before operation. Ao, aorta;

PA, pulmonary artery.

REVIEW OF PUBLISHED REPORTS

The true incidence of the anomaly is difficult to

assess. The veins are rarely studied in detail at

necropsy. Careless neck incisions., removal of the

sternum, or opening of the pericardium may cause

bleeding from the veins, which then collapse and

become very difficult to see. Removal of the heart

often damages or destroys the veins. Angiocardio-

graphy does not usually call for visualisation of the

right brachiocephalic vein. Increased routine use of

suprastemnal echocardiography, however, should

readily reveal the anomaly if such a possibility is

recognised.A detailed angiographic study of the brachio-

cephalic veins of over 1500 people showed only one

example of a subaortic vein,' while another angio-

graphic study of the superior caval veins in 510

patients with congenital heart disease showed no

such anomalies.' Sherman found two examples

among 503 specimens of c-ongenitally malformed

hearts' and we have encountered three cases out of

approximately 2000 congenitally malformed hearts

Gerlis, Ho

in the combined collections of the Brompton andKillingbeck Hospitals. These combined figures givean incidence of six cases out of about 2500 necropsycases with congenital heart disease, or approximatelyone in 500. Smallhorn et al found seven casesechocardiographically but the total number ofpatients examined in the series is not stated.5The incidence in individuals without cardiac

malformation is presumably very much lower. In apersonal necropsy series, LMG found no subaorticbrachiocephalic veins in approximately 5000 in-dividuals without malformed hearts.

In none ofthe reported cases has it been suggestedthat the venous anomaly had any adversephysiological or clinical effect. Therefore the age atdeath or diagnosis was relevant only to associated orunassociated conditions. The ages ranged from oneday to 74 years (table). In those cases with congenitalheart disease, the mean known age was approxi-mately three years (excluding a 74 year old man withan anomalous connection of the right upperpulmonary vein). In cases with normally formedhearts, the mean age at death was 53 years, support-ing the view that the abnormality is clinically benign.The sex of 15 of the 25 cases was known. Males

outnumbered females by 11 to 4. Those cases withcongenital heart malformation showed no significantsex difference but all eight cases with normallyformed hearts were male.

Features common to tetralogy of Fallot werepresent in most of the 14 cases with major cardiacmalformations. Thus a ventricular septal defect wasreported in eight cases and may have been present inanother six reported by Smallhom et al in whichintracardiac malformations ofunspecified types werefound by echocardiography.5 A right sided aorticarch was noted in ten cases and tetralogy of Fallot,pulmonary stenosis, pulmonary atresia, or unspeci-fied abnormalities of the right ventricular outflowtract were present in 11 of the 14. Other malforma-tions were: one example of double outlet rightventricle, one common arterial trunk, and ananomalous isolated subclavian artery arising from anarterial duct (see table). There were minor vascularanomalies in three additional cases in which the heartitself was normal. A 74 year old man had anomalousdrainage of the right superior pulmonary vein intothe superior caval vein8; a 19 year old man had a smallsubthyroid transverse venous anastomosis,10 and aman of 66 had minor abnormalities of the jugularvein.12 There were no instances of associated non-cardiovascular malformations.Three distinct anatomical varieties of the malfor-

mation can be recognised according to the relation ofthe anomalous vein with the arterial duct or ligament(fig 4). The presence and position of this structure

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Anomalous subaortic position of the brachiocephalic (innominate) vein

Anot: ': : sie.. r

Artic arch

Ascendng orta

'Pumory artery

Superior cova Left brachiocephalic

-Azygs

Aor/.

Pulmonary artery

duct

Fig 4 (a) Diagram showing the positions of the normal (N) and the three variants of the anomalous left brachiocephalicvein (1, 2, 3) in relation to the 4th and 6th left aortic arches as seenfrom the left side. (b) Diagrams of the normal andabnormal variant venous pathways as seenfrom thefront, with accompanying embryological diagrams.

was specified or illustrated in 13 cases. In ten, thevein passed anteriorly to the arterial duct or ligamentto lie between the underside ofthe aortic arch and thepulmonary arteries. In two cases, the vein passedposteriorly to the arterial duct or ligament, while inthe remaining case it passed below the left pulmonaryartery.' Three further cases have been described inwhich the left brachiocephalic vein passed behindone or more of the main aortic branches but wasnormally related to the aortic arch.4' 8101216 Thiscondition is distinct from the anomalous venouspathway that is the subject of this review.

543

Discussion

During normal development, the primordia of thesystemic veins first appear as paired anterior andposterior cardinal veins that unite on each side toform a common cardinal vein (or cuvierian duct) thatopens into the primitive sinus venosus. The anteriorcardinal veins extend headwards to the junctions ofthe internal jugular veins and subclavian veins oneach side, but, during subsequent development, mostof the left anterior cardinal vein disappears. Thevenous drainage from the left side of the head and

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neck and the left arm is then directed into the rightanterior cardinal vein by the development of a newtransverse anastomotic channel that becomes the leftbrachiocephalic (or innominate) vein. The short partofthe right anterior cardinal vein that lies distal to theopening ofthe left brachiocephalic vein is designatedas the right brachiocephalic vein, while the portionthat lies below, together with the right commoncardinal vein, becomes the superior caval vein. Theorifice of the (right) azygos vein represents the site ofentry of the right posterior cardinal vein and marksthe junction of the anterior cardinal and commoncardinal venous components of the superior cavalvein. On the left side the common cardinal veinbecomes the coronary sinus, the adjacent portion ofthe anterior cardinal vein becomes the oblique vein ofMarshal, and the posterior cardinal vein becomes thegreat cardiac vein (fig 5).

Phylogenetically, this venous arrangement is a latedevelopment. It is present only in primates and someof the other mammals, with no forerunner in othervertebrate orders.'7 Persistence of bilateral superiorcaval veins is a common feature in cases of cardiacmalformation and in 39%18 to 43%' of these there isno transverse communicating vein; the left sidedvenous return enters directly into an atrium.

If the lower portion of the left anterior cardinalvein atrophies while the usual transverse anastomosisfails to develop, survival depends on the opening upof an alternative anastomotic pathway within thecapillary plexus of that region. This seems to be apossible explanation of the anomalous subaorticposition of communicating vein presently described.

Gerlis, Ho

The subaortic vein enters the superior caval veinbelow the insertion of the azygos vein and it thusconnects the left anterior cardinal venous componentto the right common cardinal venous component.Normally, the left brachiocephalic vein enters thesuperior caval vein above the insertion of the azygosvein and the connection is between the left and theright anterior cardinal components. The anomalousvein, therefore, is embryologically distinct from thenormal left brachiocephalic vein as well as having adifferent spatial pathway and different anatomicalrelations. In consequence, the question of termin-ology could be debated at length. But, because theultimate connections at either end are identical, itseems reasonable to refer to the structure as ananomalous brachiocephalic vein.Although not of clinical importance, its

recognition during clinical investigation raises thepossibility of an association with other malforma-tions, especially right aortic arch, ventricular septaldefects, and right ventricular outflow obstruction.Care must be taken not to confuse the structure withother arteries or veins-notably, the centralpulmonary arteries in the presence of the pulmonaryatresia or a venous confluence in anomalouspulmonary venous connection.' From the surgicalviewpoint, the anomalous brachiocephalic vein mayhinder access to the arterial duct during ductalligation, or obscure the field in the construction of asubclavian to pulmonary shunt. Dissection in theregion of the duct must be performed carefully toavoid damaging a subaortic vein.

lorrmnlcWtent Anomlous leftchiocephetic Internal brachiocepholic

vein uir veinvein

Subclavion /

Leftatrium \Ligamefnt

0 0 d MPulmonarymA°oJ Oblimi vein veins

, @ - G®v teen

Fig 5 Diagrams showing embryological derivations of the normal and anomalous left brachiocephalic veins. (a) Earlyembryological patterns. (b) Normal definitive pattern showing the left brachiocephalic vein entering the right anteriorcardinal vein component (above the azygos vein). (c) Abnormal definitive pattern showing the left brachiocephalic veinentering the right common cardinal vein component (below the azygos vein).

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Anomalous subaortic position of the brachiocephalic (innominate) vein 545

We thank Dr Wilfred Nikolaizik for his valuableassistance in translating some of the references.

This study was supported, in part, by the BritishHeart Foundation.

References

1 Roberts JR, Dotter CT, Steinberg I. Superior vena cavaand innominate veins: angiographic study. Am JRoent 1951;66:341-52.

2 Kershner L. Zur Morphologie der Vena Cava Inferior.Anat Anz 1888;3:808-23.

3 Buirsky G, Jordan SC, Joffe HS, Wilde P. Superiorvena caval abnormalities: their occurrence rate, as-sociated cardiac abnormalities and angiographic clas-sification in a paediatric population with congenitalheart disease. Clin Radiol 1986;37:131-8.

4 Sherman FE. An atlas of congenital heart disease.London: Henry Kimpton, 1963.

5 Smallhorn JF, Zielinsky P, Freedom RM, Rowe RD.Abnormal position of the brachiocephalic vein. Am JCardiol 1985;55:234-6.

6 Daser P. Ueber eine seltene Lage-Anomalie der venaanomyma sinistra. Anat Anz 1902;20:553-5.

7 Ghon A. Ueber eine seltene Entwicklungsstorung desGefasssystems. Zbl Path 1908;19:242-7.

8 Nuitzel H. Beitrag zur Kenntnis der Missbildungen inBereiche der oberen Holvene. Frankf Z Path1914;15:1-19.

9 Martin CP. A case of congenital abnormality of theheart with apparently an unusual abnormality of thegreat vessels. J Anat 1931;65:395-8.

10 Walter L. Uber eine seltene Lageanomalie di venaanomyma sinistra webst Betrachtungen uberanomalien and Asymmetrien des Venensystems inBereich des Kopfes und Halses. Z Anat 1931;95:769-805.

11 Adachi B. Das Venensystem der Japaner. Anatomie derJapaner II. Tokyo: Kenkyusha, 1933:83-7.

12 Friedman SM. Report of two unusual venous abnor-malities (left postrenal inferior vena cava; post-aorticleft innominate vein). Anat Rec 1945;92:71-6.

13 Yoshida Y, Fukuyama U. A case of the left brachio-cephalic vein passing behind the ascending aorta.Chiba Igaku 1975;51:157-9.

14 Kitamura S, Sakai A, Nishiguchi J. A case of the leftinnominate vein passing behind the ascending aorta.Anat Rec 1981;201:567-72.

15 Cloez JL, Ravault F, MarSon F, Pemot C. Troncveineux innomine en position sous-aortique. Inter&tde l'echocardiographie de contraste par voie supra-steinale. Arch Mal Coeur 1982;75:939-43.

16 Jakubczik I, Ziegler H. Seltene Anomalein der Grossenintrathoracalen Blut und lymphgefassstamme. AnatAnz 1963;112:257-68.

17 Barnett CH, Harrison RJ, Tomlinson JDW. Variationsin the venous systems of mammals. Biol Rev1958;33:442-78.

18 Winter FS. Persistent left superior vena cava. Survey ofworld literature and report of thirty additional cases.Angiology 1954;5:90-132.

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