This document discusses various anomalies of the aortic arch including abnormal branching patterns, abnormal positions of the arch, and the presence of extra arches. It defines key types of anomalies such as double aortic arch, right aortic arch, and interrupted aortic arch. For each type, the document describes associated embryology, diagnostic methods including echocardiography and angiography, and potential treatments.

1. ANOMALIES OF AORTIC ARCH

2. ANATOMICAL CLASSIFICATION
Abnormality of branching
Abnormality of arch position
Supernumerary arch- double aortic arch
Abnormal origin of pulmonary artery from
descending aorta

3. DEFINITION:
Bronchus which is crossed by, defines the arch
2D ECHO- branching pattern of brachiocephalic vessel
First arch vessel carotid artery goes opposite to side of the arch
Exception: retroesophageal innominate artery, isolated
innominate artery and congenital absence of carotid artery
Diagnostic methods:
• Barium esophagography
• Echocardiography
• Angiography
• USG

4. A/W digeorge syndrome, velocardiofacial and conotruncal
anomaly and CATCH22
Cardiac anomaly: conotruncal anomaly
Subaortic stenosis with post malalingment of IVS
Truncus arteriosus communis
TOF+/- PA
60% of aortic arch anomaly without cardiac defect will have
22q11 deletion

5. Aortic arch anomaly in which trachea and esophagus are
completely surrounded by vascular structures- vascular ring
Structures need not to be patent
c/f- stridor, pneumonia and bronchitis and cough
apnea , choking , swallowing difficulty and interciurrent urti
Recurrent wheezing
Mistaken respirtaory symptom i/v/o cardiac anomaly
Asthma masquerading symptoms
Asymptomatic

6. Normal arch
Left arch crosses the left main bronchus at the level of thoracic
vertebra T5 and descends left of midline to the diaphragm
PDA joins distal to the take off of left subclavian artery
2 variants of left aortic arch
1)Common brachicephalic trunk –
right innominte and left carotid from
single origin
2) Separate origin of left vertebral artery from arch proximal to
takeoff of the left subclavian artery

7. Abnormal left arch
1)LAA with retroesophageal R subclavian artery (dysphagia
lusoria)
• Described by Hunald
• MC arch anomaly
• 38% in Downs syndrome
• MC form of aberrant R subclavian artery
• Branches- RCA, LCA, LSCA,RSCA retroesophgeal
• a/w- conotruncal anomalies, TOF, Interrupted arch, left sided
obstructive lesion and AV septal defect

9. Embryology-
Disappearance of R 4th aortic arch
Distal R dorsal aorta becomes the proximal r subclavian artery
forming its retroesophageal portion
R sixth arch also involutes
Diagnosis and Mx-
No innominate artery
Barium esophagography- fixed filling defect
2D ECHO- non bifurcating first branch ascends towards R

10. 2)LAA with R sided retroesophageal Diverticulum of
Kommerall:
1 st vascular ring diagnosed
Branching is same as before with difference in the size of
proximal subclavian aretryand presence of ligamentum
arteriosum
Embryology :
Distal R sixth arch persist and forms a ring

11. 3)Left aortic arch with R descending aorta and R ducutus for
ligamentum
Circumflex aortic arch
Arch becomes retroesophageal, so subclavain is not
retroesophageal
Descending aorta is connected by ductus to right RPA forming a
vacular ring
Embryology:
Left arch with retroesophageal subclavian artery
Disappearance of R 4th arch with distal left dorsal aorta forming
distal aortic arch passess retroesophageally to descending aorta
R seventh intersegmental artery arises from R side descending
aorta
R sixth arch connects RPA portion of truncoaortic sac with distal
R dorsal aorta

12. Diagnosis and Mx:
Vascular ring symptoms
Barium esophagography- large post indentation
DD- RAA with retroesophageal diverticulum
Angio , MRI
4)Left aortic arch with isolated R subclavian artery
• RSCA arises from ductus arteriosus
• Branching pattern is RCA, LCA and left SCA
• Persistence of R 6th arch from which subclavian artery arises
Diagnosis :
When ductus patent- lim sat< head sat
Ductus closes – same sat through retrograde flow- no Sx
Rx- implantation of subclavian artery to carotid artery

13. LAA with R decending aorta and
R ductus LAA with R subclavian artery

14. 5)Left aortic arch with cevical origin of right subclavian artery
a/w interrupted aortic arch, TOF with PA, and 22q11 deletion
Innominates bifurcates in neck to internal and external carotid
and subclavian and traverse back to thorax to supply arm
Embryology:
B/L or U/L absence or atresia of embryonic fourth arch
Fate of subclavian artery if atresia or absence occurs on side
opposite to aorta
1) Origin from descending aorta ( distal to intersegmental artery)
2) Origin from sixth arch
3) Origin from third arch- more cephalad than fourth ,
subclavian from neck

15. When 4th arch is absent or atretic ipsilateral to definitive aortic
arch – 3 possibilities
1) Interrupted aortic arc in which sixth arch replaces 4th
2) Persistent fifth aortic arch with atresia of distal 4th
3) Cervical aortic arch – 3rd arch replaces 4th

17. Right aortic arch
Single aortic arch that crosses over right main stem bronchus
passing R of the trachea
4 main types of R arch:
a) Mirror –image branching of R descending aorta
b) With retroesophageal left subclavian artery
c) With retroesophageal diverticulum of Kommerall
d) With R descending aorta
Incidence- 13 to 34%
A/w Truncus> TOF> D-TGA
RAA with CoA- 1.7% of all CoA, 2.9% of RAA
Abberant LSCA- 65%

18. 1)RAA with mirror image branching:
Branches- left innominate artery RCARSCA
Ductus arteriosus from left side or base of innominate artery
A/W CHD – TOF, TA, TGA,DORV
Right bronchus compression btw RPA and DA
Embryology:
Dissolution of left dorsal aorta distal to the origin of 7th
intersegmental artery
Right 6th arch involutes and left 6th arch persist
Left ductus arise from underside of left innominate artery and
passess to RPA appears as congenital BT shunt
Left sixth arch disappears and right persist – true mirror image

19. Diagnosis and management:
Incidental imaging
2D Echo
CXR- right sided indentation
Barium esophagography- right sided indentation on trachea
Rx- no trrearment
For systemic to pulmonary shunts, anatomy must be known
For repair of esophageal atresia and TEF

20. RAA with Mirror image branch

21. 2)RAA with retroesophageal LSCA
Non vascular ring form of anomalous or aberrant subclavian
Sequence- LCA, RCA, RSCA and retroesophageal LSCA
A/W conotruncal anomaly and 22q11 deletion
Embryology:
Similar to R arch with retroesophageal diverticulum with
involution of left 4th arch but loss of left 6th arch
Left dorsal aorta becomes proximal L SCA
R sixth arch connects LPA with R dorsal aorta
Diagnosis and Mx:
Barium esophagography- post indentation on left
No vascular ring- trachea unaffected
2D echo- arch 1st branch LCA
MRI and Angiography

23. 3)RAA with retroesophageal diverticulum of Kommerall:
Second most common vascular ring after double aortic arch
Branches: LCA, RCA, right subclavian artery, and finally a
retroesophageal vessel from which the left subclavian artery
arises and the left ductus arteriosus connects
ring formed by the aortic arch on the right, retroesophageal vessel
supplying the left subclavian posteriorly, the ductus on the left,
and the pulmonary artery anteriorly
Congenital absence of the left carotid artery is a rare association
with right arch, diverticulum of Kommerell
Embryology:
Disappearance of the left fourth embryonic arch with persistence
of the left sixth (ductal) arch between the truncoaortic sac
(pulmonary artery precursor) and left dorsal aorta

25. The presentation in symptomatic patients is usually that of a
vascular ring
Barium esophagram reveals a large posterior indentation on the
esophagus
Angiography demonstrates the characteristic branching pattern
and abrupt change in caliber from diverticulum to subclavian
artery
MRI /CT
The majority of people with this arch anomaly are asymptomatic.
Treatment -division of the ductus or ligamentum through left
thoracotomy.

26. Also resection of the diverticulum and transfer of the left
subclavian artery to the left carotid artery

27. Right Aortic Arch with Left Descending Aorta
and Left Ductus (Ligamentum) Arteriosus(um
Circumflex right arch
Aortic arch cross the midline to the left at the level of the T4 or
T5 vertebral body at which point it gives rise to the left ductus
arteriosus
Branching - mirrorimage branching pattern-left innominate, right
carotid, right subclavian
Left carotid, right carotid, right subclavian, and finally the left
subclavian
Aberrant left innominate artery-right carotid, right subclavian,
left innominate as the last vessel
Aortic arch is retrooesophageal in all cases, not the branches

28. Two forms exist with dissolution of either the left dorsal aorta
distal to the takeoff of the left subclavian artery or the left
fourth arch
The persistent left sixth arch connects to the left sided dorsal
aorta completing a vascular ring
Diagnosis and management:
Barium esophagography: downward and left indentation
Division of the vascular ring is indicated when patients are
symptomatic (usually loose)
Division of the aortic arch with mobilization of the
retroesophageal portion and reanastomosis of ascending and
descending aorta using a tube graft may be necessary to relieve
the esophageal compression (in adults)

30. Cervical aortic arch
Arch is found above the level of clavicle as high as C2 vertebra
2 types:
1)Anomalous subclavian artery and vascular ring with either
descending aorta contralateral to arch or retroesophageal
diverticulum
2)Normal branching pattern
1st group- RAA asso present
Separate origin of ICA and ECA from arch
Common carotid artery or bicarotid trunk and subclavian
separately
In contralateral DA- vascular ring by AA on R, retroesophageal
segment of aorta posteriorly , ligamnetum arteriosum to left
and PA anteriorly

31. 2nd type: With LAA
AA obstruction is uncommon
A/W CoA in ring and non ring group
Embryology :
Dissolution of embryonic 4th arch
Presence of ductus caroticus (segment of dorsal aorta between
3rd and 4th embryonic arch)
Both ICA and ECA arise from 3rd arch
A/W 22q11 deletion
Alternative explanation: failure of normal descen tof aortic arch
system from cephalic location @3rd week to intrathoracic @7th
week

32. Diagnosis :
Pulsatile mass in supraclavicular fossa
In infants- stridor , dyspnea and repeated LRTI
Subclavian steal syndrome
Compression of mass- loss of femoral pulse
X ray-
widened mediastinum
Absent aortic knob
Anteriorly deviated trachea
Angiography :
2D Echo:

33. Treatment :
Ind: Arch hypoplasia and vascular ring aneurysm
Left sided ascending to descending aorta anastomosis or tube
graft interposition
Double Aortic Arch:
Anomaly in which both right and left aortic arches are present
Variations:
a) Both arches of similar size
b) Hypoplasia of one arch (Left)
c) Atresia of one arch( left)
Ductus or ligamentum may be present
Right arch is more superiorly located
DAA form vascular ring around trachea and esophagus

34. Branching pattern is determined by patency of various arch
component and side of descending aorta
Both arch patent- symmetrical origin of arteries
Atretic left arch- distal to origin of left subclavian ( RAA with
mirror image pattern)
Atretic right arch btwn LSCA and left carotid (RAA with
retroesophageal diverticulum of Kommerall)
A/w TOF> TGA>CCTGA
Embryology: Persistence of both 4th embryonic arch
Diagnosis-
Tight rings/ both arches patent – present in first week of life
With atretic left arch (loose ring)- present at 3-6 months of life
Adult: sesllowing difficulty or resp symptoms

35. Xray: tracheal indentation- sup right sided arch and inf left sided
arch
Lateral view- posteriorly indentation by right arch
Treatment :
For symptomatic parient:
Division of ring in its smaller limb
Ductus arteriosus must be considered
Persistent fifth arch:
Double lumen aortic arch- both arches appears on same side
Variations:
With both lumen patent
Atresia/interruption of superior arch with patent inferior arch(5th )
Hypoplastic but patent superior arch

36. Inferior arch extends from innominate artery to a point opposite
to take off to the LSCA
Incidental or a/w CoA
Diagnosis and management:
Angiography
Echocardiogrphy
MRI

37. Interrupted aortic arch
Complete separtion of ascending and descending aorta
Anomalies related to the pattern of branching of brachiocephalic
vessels
Caloria and Patton classification:
Type A- interruption distal to LSCA
Type B- Between carotid and LSCA
Type C- Between carotids
With retroesophageal or isolated subclavian artery
With retroesophageal subclavian
With isolated subclavian artery

38. Interrupted RAA – in Digeorge syndrome
Type B more common than type A
Type A in AP window, TGA and innterrupted aortic arch
Embryology:
Type A – involution of both dorsal aorta distal to 4th arch and
proximal to persistent sixth arch
B- involution of one 4th arch and one dorsal aorta btwn arch 4
and 6
C- involution of one limb of truncoaortic sac and associated
proximal third arch and entire fourth arch

39. Diagnosis and management:
CV collapse and heart failure after spontaneous closure of ductus
arteriosus
Fluid resuscitation
PGE1 infusion for ductal patency
Ionotropic support
Absence of all limb pulse – type B with anomalous subclavian
Strong carotid pulse- diff critical AS from interrupted aortica arch
Differential cyanosis
2DEcho and Angiography
MRI

40. Surgery depends on degree of subaortic obstruction
Subaortic diameters>/=5-6mm- intracardiac repair and arch
reconstruction
Subaortic diameter 4mm or less- homograft augmentation of
ascending aorta using pulmonary artery
IAA with TGA- ASO with transannular patch