Transcript Aortic arch anomalies

Aortic arch anomalies
Dr.Deepak Raju
Embryology
• Heart is first seen in the form of two endothelial heart
tubes-18th day of foetal life
• Fusion results in a single tube with a series of
dilatations(sinus venosus ,atrium ,ventricle &bulbus
cordis) and begins to beat by 22nd day
• Bulbus cordis represents arterial end of the tube-prox
part conus,distal truncus arteriosus
• First arteries to appear are right and left primitive aorta
connected to the endothelial heart tubes
• Portion lying ventral to foregut(ventral aorta)connected to first pharyngeal arch-to the portion
dorsal to foregut(dorsal aorta)
• After the fusion of endocardial heart
tubes,ventral aorta fuse to form aortic sac
• Truncus continues with the aortic sac from which
right and left pharyngeal arch arteries arises
• They arch backward on lateral side of foregut –
continues as right and left dorsal aorta-fuse to
form descending aorta
• During 4th and 5th week,successive arterial arches
appear in 2nd to 6th pharyngeal arches
• Each connects ventrally to aortic sac&dorsally to
dorsal aorta
• Greater part of 1st &2nd arch arteries disappear.1st
arch remnant-maxillary artery,2nd arch remnant –hyoid
and stapedial artery
• 5th arch artery regress completely
• 3rd and 4th open to ventral part of aortic sac.6th to
dorsal part.
• Spiral septum formed in truncus in the 5th week
extends to aortic sac.blood from pul.artery goes to 6th
arch artery,from aorta to 3rd &4th arch arteries.
• Dorsal aorta gives lateral intersegmental branches to
body wall.7th cervical intersegmental supplies upper
limb bud.
• Portion of dorsal aorta b/w 3rd and 4th (ductus
caroticus)disappear
• Each 6th arch artery connects to the
pulmonary vascular tree.portion b/w this
connection and dorsal aorta-ductus
arteriosus-regresses on right side
• 3rd-common carotid and prox.int.carotid
• 4th –
– Lt.-aortic arch b/w LCCA and LSCA.
– Rt-prox RSCA
• 6TH –
– prox part –prox pul art
– distal part-ductus on left and right side involutes
• Lt dorsal aorta-aortic arch distal to LSCA
• Rt dorsal aorta– cranial portion-RSCA distal to 4th arch.
– distal portion-involutes
Edward s double aortic arch model
• Anomalies of aortic arch to be conceptualised
as variations in regression of different
segments from the hypothetical double arch
Totipotential aortic arch diagram
History
Anomalous RSCA-Hunauld,1735
Double aortic arch-Hommel 1737
Right aortic arch –Fioratti,Aglieti-1763
Interrupted aortic arch-Steidele-1788
Bayford,1787-dysphagia by vasc ring-coined
term dysphagia lusoria
Gross,1945-first division of a vasc ring
Sidedness of the arch
• Left and right arch refers to which bronchus is
crossed by the arch
• Echo or angio-branching pattern of
brachiocephalic vessels
• First arch vessel that contains carotid artery
opposite side of arch
• Retroesophageal or isolated vessels-opp to
side of arch
• MRI and CT-conclusive
Anatomical classification
• Abnormalities of branching
• Abnormalites of arch position-cervical
arch,right arch
• Supernumary arches-double aortic arch and
persistent 5th arch
• IAA
• Anomalous origin of pulmonary artery branch
Clinical classification
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Vascular rings
Non-ring vasc.compression
Non-compressive arch malformations
Ductal dependent arch anomalies
vascular ring-aortic arch anomaly in which
trachea and esophagus surrounded by vasc.
structures
Double aortic arch most common(40%),rt.aortic
arch with lt.ligamentum(30%),aberrant
RSCA(20%),anomalous innominate(10%).
• Symptoms– Stridor,Pneumonia,bronchitis
– Reflex apnoea or choking on eating
– Hyperextension of neck
– Increased resp distress a/w intercurrent
resp.infections
– swallowing difficulty
• 3 d΄s opposite to side of archdiverticulum,dimple,descending aorta
• Diverticulum –large vessel from desc.aorta
giving rise to a smaller calibre vessel with a
sudden taper
• Dimple –tapered blindly ending outpouching
• Descending aorta in upper thorax opp.to side
of arch-connected by ligamentum arteriosum
Normal left arch development
Variants of left aortic arch
• Common brachiocephalic trunk
– Right innominate and left carotid from single
origin
– 10% of normal
– Compression of trachea possible
• Separate origin of left vertebral artery
– 10%
– Prox to LSCA
– 3rd arch vessel smaller than 4th
Lt arch with retroesophageal RSCA
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0.5% incidence
m.c.arch anomaly
38% of down′s
Disappearance of Rt 4th arch-distal Rt dorsal aorta
becomes prox RSCA
Rt 6th arch disappear
Usually asymtomatic
Barium –smaller filling defect on postr aspect of
esophagus slanting upward
Angio-earlier filling of Rt carotid on aortic root
injection
Lt ao.arch and retroesophageal
diverticulum of Kommerell
• First vasc ring to be diagnosed during life
• Similar to previous except for persistent 6th
arch-ligamentum which completes a vasc .
Ring
• Prox.RSCA dilated to form diverticulum
Lt ao.arch,rt.desc
aorta,rt.ductus(circumflex aortic arch)
• Branching pattern similar to earlier-arch
retroesophageal,RSCA the last arch vessel is
not retroesophageal
• Desc.aorta connected to RPA by ligamentumforms vasc.ring
Lt ao arch &isolated RSCA
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Right 6th arch persists
RSCA from rt ductus
RSCA and vertebral fills from PA in foetal life
When ductus closes-retrogradely from circle
of willis
– Vertebrobasilar insufficiency
– Congenital subclavian steal
– Absent rt arm pulse
Lt ao arch with cervical origin of Rt
subclavian
• Marker of 22q11 deletion
• Innominate trifurcates in the neck-RSCA
travels back to thorax
• Subclavian origin from 3rd arch
Right aortic arch
• A single aortic arch that crosses rt mainstem
bronchus
• 13-34% in TOF
• 30-40% in truncus arteriosus
• 20% in pul.atresia with VSD
• 7.7% in tricuspid atresia
• 8-10% in transposition
Right aortic arch-mirror image type
• Sequence of arch vessels-lt.innominate,rt
carotid,RSCA
• Ligamentum lt sided
• No vasc ring.can form rarely if Lt. ductus from
rt desc aorta
• CCHD in 98%(48% TOF)
Rt ao arch with retroesophageal
diverticulum of Kommerell
• Sequence –lt carotid,rt carotid ,RSCA,a large
retroesophageal vessel( diverticulum) from
which LSCA arises
• Lt ligamentum completes the ring
• Disappearance of Lt 4th arch and persistence
of 6th arch
Rt arch with retroesophageal LSCA
• Similar to previous one except for the absence
of retroesophageal diverticulum
• Ductus is rt sided
• No vasc ring
• Involution of lt 4th and 6th
Rt arch with Lt desc aorta and Lt
ligamentum
• Aortic arch itself crosses midline-connects to lt
ductus to form vasc ring
Cervical aortic arch
• Arch found above level of clavicle
• Two categories-normal branching pattern or
anomalous subclavian artery and vascular ring
• 2nd group-devided acc.to carotid origin(bicarotid
trunk or separate origin of ext.&int carotid)
• Mechanism– Failure of normal descent of aortic arch system
– Persistence of ductus caroticus&involution of 4th arch3rd arch becomes definitive aortic arch with separate
origin of ext &int carotid from it
Double aortic arch
• Both rt and lt arches present
• Persistence of both rt and lt 4th arch which join TA sac
to dorsal aorta both of which persist
• Only one 6th remain
• Rarely a/w other CHD, when present-TOF most
common
• Both arches can be patent or one hypoplastic or
atretic(usu.left)
• Form complete vasc.rings
• Symmetric origin of 4 arch vessels from respective
arches when both patent
Persistent 5th arch
• First reported by Van praagh in 1969
• Double lumen aortic arch in which both arches
appear on same side of trachea
• 2 common sub categories– Subway vessel beneath normal arch(4th arch)that
extend from innominate to take off of LSCA
– Double lumen aortic arch with atresia of superior
arch with patent inferior arch-common origin of
all brachiocephalic vessels from asc.aorta
Interrupted aortic arch
• Defined as complete separation of ascending
and descending aorta
• Celoria and Patton classification(1959)
– Type A-interruption distal to SCA that is ipsilateral
to 2nd carotid artery
– Type B-interruption b/w 2nd carotid and ipsilateral
subclavian
– Type C-interruption b/w carotids
• Each of the types subcategorised to 3 types
– 1.without retroesophageal or isolated subclavian
artery
– 2.with retroesophageal subclavian artery
– 3. with isolated subclavian artery
• Interrupted rt arch seen only in DiGeorge syn.
• Type A-aorticopulmonary septal defect,TGA
• Type B-m.c,a/w conotruncal anomaly,DiGeorge
syn.
• Type C-rare
• Type A-involution of both dorsal aorta distal to
4th arch,prox to persistent 6th arch
• Type b-involution of one 4th arch and one
dorsal aorta b/w 4th and 6th
• Type C-involution of one limb of truncoaortic
sac
• Present with acute cardiovasc collapse after
closure of ductus
• Absence of all limb pulse with strong carotid
pulse suggest type B with anomalous
subclavian
Anomalous origin of pulmonary artery
from ascending aorta
• Anomalous pulmonary artery branch arising from
ascending aorta in presence of a MPA arising separately
• Anomalous RPA– More common
– Embryonic branch pul.artery joins rt side of TA sac,but fails to
join MPA before septation
– High incidence of aorticopulmonary septal defect
• Anomalous LPA
– a/w TOF in 74%
– Embryonic branch pul.artery fails to join TA sac
• CCF in infancy f/b early devt of pulmonary vascular disease
Anomalous origin of LPA from RPA
• LPA arises from RPA and passes b/w trachea
and esophagus-pulmonary artery sling
• Tracheal compression-severe resp distress and
stridor
• Isolated anomaly,rarely a/w TOF
• LPA passes beyond trachea before joining TA
sac
• Anterior indentation on barium swallow
Summary
• Aortic arch anomalies and vascular rings can
be interpreted on the basis of embryology
• With the devt. Of MRI and CT 3-D
reconstruction is possible
• Intervention required only when symptomatic
or when a/w other cardiac anomalies
• Thank you