1、Vascular Anomalies of Aorta,Pulmonary and Systemic vessels1Overview of Arch Anomalies1.Aberrant Right subclavian artery.2.Innominate artery compression syndrome.3.Right Arch Mirror Image.4.Right Arch with Aberrant left subclavian.5.Double Aortic Arch.6.Double Arch with Atretic Segment.2Embryology Do
2、uble Arch:In the embryo a double arch with two brachiocephalic vessels on each side is present.If double aortic arch persists,it forms a vascular ring around trachea and esophagus.Double Arch with Atretic Segment:Posterior part of the left arch becomes atretic.This remnant persists as a fibrous cord
3、 tethering the anterior left arch to the descending aorta.3 Normal Left Arch:The posterior part of the right arch involutes.The two brachiocephalic vessels on the right form the right innominate artery.Right Arch with mirror branching:Mirror image of normal left arch.Posterior part of the left arch
4、involutes.The two brachiocephalic vessels on the left form the left innominate artery.4Left Arch with aberrant right subclavian artery:Right arch between the right subclavian and right common carotid artery involutes.First branch is the right common carotid,followed by the left carotid and the left
5、subclavian artery.The last branch is the right aberrant subclavian artery.Right Arch with aberrant left subclavian artery:Mirror image of the left arch with aberrant right subclavian First branch is left common carotid,followed by right carotid and right subclavian artery.The last branch is the left
6、 aberrant subclavian artery.5Aortic Arch AnomaliesRight Arch Mirror ImageThis is the mirror-image variety of the left arch.a 2 year old girl with wheezing and coughing.On the axial image there is a right arch.On the VR there is mirror image branching of the brachiocephalic arteries,no aberrant subcl
7、avian artery,so this is a right arch mirror image.6This anomaly is asymptomatic,because there is no obstructing ring.Almost all of these patients however come to our attention because they have associated congenital heart disease in 98%of cases.This patient had a mirror image aortic arch and a VSD.7
8、above an adult who was operated in his childhood for a Tetralogy of Fallot(pulmonary stenosis,right ventricular hypertrophy,VSD,overriding aorta).At surgery the VSD was patched and the pulmonary outflow tract was enlarged.Notice that there is also a right arch.8Right Arch with Aberrant left subclavi
9、an The Right Aortic Arch with an aberrant left subclavian is an obstructing arch anomaly.9Below a patient with a right arch with an aberrant left subclavian(indicated by the yellow arrow).The yellow arrow indicates the azygos vein.?The green arrow indicates the left superior intercostal vein,a norma
10、l variant,that we will discuss later.10Posterior oblique view:Right Arch with Aberrant left subclavian(yellow arrow)In a mirror type right arch,the left subclavian is the first brach and forms the left innominate together with the left common carotid.11Below a symptomatic child.On the axial image th
11、ere is a right arch with the left subclavian artery that comes off on the posterior side and runs behind the trachea and the esophagus.The compression of the trachea is demonstrated on VR12Double Aortic ArchOn the left a chest film of a 6-month old boy with stridor and cough.The trachea is deviated
12、to the left,otherwise the chest film is normal.So there is some mass effect on the right side.On the left the reconstructions demonstrating a double aortic arch.There are branches coming off the right arch and branches coming off the left arch.13The right arch is typically larger and higher than the
13、 left.There is a complete ring that encircles the esophagus and the trachea and usually there is stridor or dysphagia.Two brachiocephalic arteries arise on each side separately(four vessel sign)and there is no brachiocephalic artery.14Above a chest film of a young adult with a cough.There is a right
14、 paratracheal mass.The differential diagnosis is tumor,adenopathy or vessel(right arch,dilated azygos vein,dilated aberrant right subclavian artery).15The findings are:1.four vessel sign 2.double arch3.right arch higher and larger4.esophagus and trachea are completely encircled 16The narrowing of th
15、e trachea is seen on the axial images,but better appreciated on the MPR and VR17Above preoperative and postoperative MDCT studies of a 2-month-old female infant with double aortic arch presenting with stridor and repeated apnea.The smaller left arch is partially resected.18Double Arch with Atretic S
16、egment Occasionally the double arch can have an atretic segment.You should not confuse it for a right arch.The left arch is just very small and there is still a four vessel sign.19Above a dominant right arch and a small left arch.The atretic segment is marked by the arrow.Notice the four vessel sign
17、.20On a posterior view the interruption is nicely demonstrated.Remember that there is still a ring,so there is still obstruction.21Another case Above.Do not call this a right arch.It still is a double arch and there is a atretic fibrotic segment on the posterior side of the left arch,that completes
18、the ring.Notice the four vessel sign.22Same patient.Always look at the airways.On the reconstruction the impression on the trachea is better appreciated.23Left Arch Aberrant Right SCA Also known as arteria lusoria.Most common arch anomaly.Not a true ring Usually asymptomatic.24Aberrant Right SCA,no
19、compression of the tracheaAbove a young patient,who has a CT for another reason.Notice that there is a left arch,but the right subclavian artery is the last brachiocephalic artery to branch off the arch.25Only rarely these patients become dysphagic,when the origin of the right subclavian artery beco
20、mes dilated.On a barium study of the esophagus you will see a posterior impression with an oblique course directed towards the right shoulder.Below a 78 year old woman with dysphagia.There is consolidation in the right upper lobe,maybe due to aspiration.There is a dilated vessel that compresses the
21、esophagus and it originates from the left-sided aorta,i.e.an aberrant right subclavian artery.26Dysphagia in patient with dilated aberrant right subclavian artery.27 the same patient with dilated aberrant right subclavian artery.Coronal reconstruction.28 Below another patient with an aberrant right
22、subclavian.When you follow the artery from inferior to superior,it starts on the left side of the arch and travels obliquely behind the esophagus to go to the right.2930a 5 year old girl with noisy breathing and occasional cyanosis.The findings are:1.anterior compression of the trachea 2.brachioceph
23、alic(innominate)artery is located more to the left and compresses the trachea Innominate artery compression syndrome 31 The diagnosis is the innominate artery compression syndrome.In infants the innominate artery arises more to the left than in adults,so its got to go in front of the trachea.It may
24、compress the trachea,leading to stridor,cough and dyspnea.This compression decreases with age.32The compression in the innominate artery compression syndrome is located on the right anterior side and at the level of the thoracic inlet.33On the left another case with mild compression on the trachea.3
25、4 Narrowing at level of distal arch/descending aorta.Chest film:figure 3 sign,inferior rib notching.Intervention when gradient 20 mm Hg.Associated with bicuspid aortic valve(75%),cerebral aneurysms(5-10%)and Turner syndrome(20%have coarctation)Aortic Coarctation35The findings are:Large thymus which
26、is normal for a 2 month old.Striking discrepancy between diameter of ascending and descending aorta.The diagnosis is coarctation,which is nicely demonstrated on the posterior view of the reconstruction.a 2 month old boy with heart failure.36There are two types of coarctation.The type we usually see
27、is the post-ductal type,which is distal to the left subclavian artery.The uncommon pre-ductal type is seen in neonates.They present with severe heart failure,mostly within the first week of life,usually on the first day.The occlusion is in front of the left subclavian.37Intercostal collaterals in ao
28、rtic coarctationThe intercostal collaterals typically occur between the 3rd and the 8th rib.38The findings are:Big internal mammarian arteries on the axial image due to a high grade stenosis as a result of a coarctation.Probably could not make the diagnosis based on the axial images alone.Post-ducta
29、l coartation only seen on sagittal reconstruction.Intercostal collaterals.39Above two neonates with the pre-ductal type of coarctation.The stenosis is in front of the left subclavia and there is arch hypoplasia.Collaterals do not occur,probably because they dont have time to develop.Pre-ductal type
30、of coarctation40Coarctation is treated with angioplasty,stent placement or patch aortoplasty.The image on the far left is the result after angioplasty.Next to it a patient who was treated with a stent.Notice that the stent is obstructing the orfice of the left subclavian artery.41 Below On the far l
31、eft a patient who was treated with a stent.But the stent ruptured causing restenosis.Next to it two patients with pseudo-aneurysm.One after angioplasty and another who developed a pseudo-aneurysm after stent placement.They have to be repaired because they will rupture.Pseudo-aneurysms are seen in 10
32、%after angioplasty.30%after patch aortoplasty.42Pseudo-aneurysm in coarctation treated with stent-placement 43Pulmonary Arterial anomalies They most common anomalies of the pulmonary arteries are listed in the table on the left.44Pulmonary agenesis Also called congenital interruption of the pulmonar
33、y artery.Unilateral absence of the pulmonary artery.Small lung and hilum.Compensatory hyperinflation of contralateral lung with herniation.Below a young adult,who had cyanotic spells as a child.She is now in good health and comes in for another reason.On the chest film the differential is atelectasi
34、s,pneumonia or maybe a tumor.45Pulmonary agenesis on the right sideThe CT shows,that he right lung is not developed and the space around the atresic pulmonary artery is filled with fibrofatty tissue with collaterals.So this is pulmonary agenesis46Pulmonary agenesis on the left sideAnother case of ab
35、sent pulmonary artery with absence of lung development.On the CT the left lung is absent.These patients may be totally asymptomatic.47Pulmonary SlingBelow a 4 month old girl with abnormal echo,benign heart murmur and no respiratory or feeding difficulties.The sagittal reconstruction shows an anomalo
36、us vessel on the posterior side of the trachea.There is a little mass effect on the trachea.48In pulmonary sling,the left PA originates from the right PA and courses between the esophagus and the trachea,where it compresses the right main bronchus.Pulmonary sling is seen more frequent in children as
37、 it is more symptomatic than in adults,because the chest is smaller,but you can also encounter it in adults.49Below a child with wheezing and dyspnea.The left PA comes off the right PA and runs between the esophagus and the trachea.Some of these patients also have long segment stenosis in the trache
38、a because of cartilagenous rings.Pulmonary Sling with long segment stenosis of the trachea.(Courtesy J.Schoef)50Patent Ductus ArteriosusBelow an adolescent with a murmur.On axial image and reconstruction the patent ductus arteriosus is seen.51The ductus arteriosus is the communication between the pu
39、lmonary artery and the proximal descending aorta.It shunts blood in utero from the right ventricle to the aorta to bypass the non-functioning lungs.On the first day of life there is a functional closure and an anatomic closure with fibrosis in the first two weeks.If it does not close these patients
40、come to attention either with a murmur or later with pulmonary hypertension.52On the left a young adult with a murmur.The cardiologists are not interested in the flow direction,but just want to confirm the diagnosis.Notice the connection between the pulmonary artery and the descending aorta.53When t
41、he duct closes it may also calcify.This a normal ariant.54Pulmonary venous anomalies Partial Anomalous Venous Return The most common features of PAVR are listed in the table.55 The anomalous veins drain into the following structures:RUL:SVC association with sinus venosus-type ASD.RLL:IVC(usually),so
42、metimes Portal or Hepatic vein.Can be isolated finding or combined with pulmonary hypoplasia(Scimitar syndrome).LUL:Brachiocephalic vein(isolated finding).LLL:rare(if you find a case publish it).56Right upper lobe anomalous venous returnBelow a 2 month old,who is asymptomatic but has a murmur on phy
43、sical examination.There is a connection between the SVC and a pulmonary vein,so this is an anomalous venous return.57All these partially anomalous pulmonary venous returns are left to right shunts,but when small,they are clinically insignificant.When there is a significant shunt,they may cause(late)
44、pulmonary hypertension as seen in the case on the left.The chest film in this adult shows large pulmonary arteries and a large right atrium and ventricle as a result of pulmonary hypertension.5859Right upper lobe anomalous return(2)Below a patient with a murmur.There is an anomalous return of the ri
45、ght upper lobe to the SVC.At a slightly inferior level there is also an ASD.Contrast is seen going almost immediately into the left atrium.This type of ASD is called the sinus venosus-type ASD.6061A similar case.Notice the anomalous return of the right upper lobe vein into the VCS and the additional
46、 ASD at a lower level.62The vein drains into the IVC.The anomalous vein gently curves to the right cardiophrenic angle and is shaped like a Turkish sword(Scimitar)Right lower lobe anomalous return63Right lower lobe anomalous venous return into the azygos vein.On the left another right lower lobe ano
47、malous return.The vein drains into the azygos vein.Upper lobe veins may also drain into the azygos vein.64A 10 year old girl suspected of having pneumonia.Study the images carefully,because there are three findings and then continue reading.The findings are:Small right lung due to hypoplasia Anomalo
48、us venous returnRight aortic archThis patient has a scimitar syndrome and also a right arch.So the lesson is,that when you see one anomaly,look for another one.6566Scimitar syndromeThe features in scimitar syndrome are listed in the table 67Scimitar syndrome with a hypoplastic right lung.Another pat
49、ient with a scimitar syndrome.There is a hypoplastic right lung with mediastinal shift and there is anomalous venous return.Notice that on the coronal MIP you can nicely see the difference in vascularization of the lungs with hypovascularity on the right.68Notice how the left upper lobe vein runs fr
50、om the hilum cranially into the brachiocephalic vein.Left upper lobe anomalous venous return into brachiocephalic vein.69The differential diagnosis of a left upper lobe anomalous venous return into brachiocephalic veins is a left Superior Vena Cava(SVC).A left SVC however drains into the coronary si
