both great arteries arise 50% or more from the right ventricle (RV).
Diagram of the Embryological origins and Consequences of Conotruncal Malformations in a D Loop embryology bilateral conus DORV growth resorption normal mitral to aortic continuity transposition D transposition double outlet right ventricle Ashley Davidoff art copyright 2019 06394c01L.800s TheCommonVein.net
Common Conotruncal Abnormalities The image reflects the relationship of the aorta and pulmonary arteries in the normal patient, in DTGA, LTGA and DORV. In the normal patient with D loop the aorta (Ao) is posterior and to the right, and the pulmonary artery (PA) is anterior and to the right. In the patient with DTGA, the Ao is anterior and to the right and the PA is posterior and to the left. In an L loop the Ao is anterior and to the left and the PA is posterior and to the right. In double outlet right ventricle (DORV) the great vessels lie side by side and in DORV with a D loop the aorta is to the right and with an L loop the aorta is to the left 86778 01639 01639d02 01639d04 01639f03.jpg Anterior aorta = Transposition Ashley Davidoff MD TheCommonVein.net Ready to Connect At this stage the heart is close to totally septating but before this happens the left ventricle and aorta have to connect in order to create a systemic circulation that is separate from the pulmonary circulation. The aorta lies to right of the pulmonary artery and still has a subaortic conus. In order to connect with the left ventricle and mitral valve, the subaortic conus has to resorb. Mr Aorta has a his eyes set on Ms Mitral Valve Ashley Davidoff MD TheCommonVein.net
DORV is an arrested phase of development when both great vessels are above the RVand both still have a conus. The vessels lie side by side.
Double Outlet Right Ventricle (DORV) with Bilateral Conus and Subpulmonic VSD The axial CT of a 9 year old male reveals a findings characteristic of DORV with both great vessels lying side by side with bilateral conus (bottom images). The aorta was to the right and pulmonary artery to the left reflecting a D loop . There was a subpulmonary VSD and hence the diagnosis is Taussig Bing anomaly. 07207e01c01 heart cardiac aorta pulmonary artery RVOT conotruncal malformation DORV Taussig Bing position connection relation embryology CTscan Davidoff MD 28994 28995 28996 28997 28998 28999 MRI Ashley Davidoff MD TheCommonVein.net
01492b04L heart cardiac right atrium left atrium right venricle left ventricle atrioventricular canal conus arteriosus truncus arteriosus aortic arches RA LA RV LV AVC embryology Davidoff drawing Davidoff MD
Variations
a – similar to tetralogy of Fallot
near-normal length of conus beneath the pulmonary valve and minimal conus beneath the aortic valve. The aorta is closer to the LV and VSD closer aorta so aorta gets oxygenated blood
b – bilateral conus
equal bilateral conus, Taussig Bing
c – similar to TGA
conus mostly under the aortic valve but has a small amount of conus under the pulmonary valve so pulmonary valve and PA is closer to VSD and so PA gets oxygenated blood and Ao gets deoxygenated blood
d – many ?shades of gray,? –
The site of the VSD may vary and can affect the clinical manifestations and the options for surgery. The illustration below shows several variations. The upper left diagram (1) shows an abnormality similar to Tetralogy of Fallot, but without obstruction to flow to the lungs. Repair involves placement of a patch within the right ventricle to direct LV flow to the aorta. In the type called the ‘Taussig Bing’ anomaly (top right diagram 2) blood from the LV passes through the VSD to the Pulmonary Artery, whilst blood from the RV tends to be directed mainly to the Aorta. This is similar in many ways to Transposition with a VSD and It may be treated with an ‘Arterial Switch’ operation along with a patch within the right ventricle to direct flow to the arterial valve adjacent to the VSD. The illustration labelled ‘Doubly Committed VSD’ (3) shows a rare variant which may be suitable for repair in a similar way to the first type. The fourth diagram shows a ‘Non Committed VSD’ (4) in which the VSD is distant from both arteries and blood ‘mixes’ in the right ventricle. This is sometimes suitable for repair but in other cases a Fontan procedure may be considered. Double-Outlet Right Ventricle Gail E. Wright et althoracic key.com The site of the VSD may vary and can affect the clinical manifestations and the options for surgery. The illustration below shows several variations. The upper left diagram (1) shows an abnormality similar to Tetralogy of Fallot, but without obstruction to flow to the lungs. Repair involves placement of a patch within the right ventricle to direct LV flow to the aorta. In the type called the ‘Taussig Bing’ anomaly (top right diagram 2) blood from the LV passes through the VSD to the Pulmonary Artery, whilst blood from the RV tends to be directed mainly to the Aorta. This is similar in many ways to Transposition with a VSD and It may be treated with an ‘Arterial Switch’ operation along with a patch within the right ventricle to direct flow to the arterial valve adjacent to the VSD. The illustration labelled ‘Doubly Committed VSD’ (3) shows a rare variant which may be suitable for repair in a similar way to the first type. The fourth diagram shows a ‘Non Committed VSD’ (4) in which the VSD is distant from both arteries and blood ‘mixes’ in the right ventricle. This is sometimes suitable for repair but in other cases a Fontan procedure may be considered. Royal Children’s Hospital in Melbourne
DORV From Slide Player Double Outlet Right Ventricle (DORV) with Bilateral Conus and Subpulmonic VSD The axial CT of a 9 year old male reveals a findings characteristic of DORV with both great vessels lying side by side with bilateral conus (bottom images). The aorta was to the right and pulmonary artery to the left reflecting a D loop . There was a subpulmonary VSD and hence the diagnosis is Taussig Bing anomaly. 07207e01c01 heart cardiac aorta pulmonary artery RVOT conotruncal malformation DORV Taussig Bing position connection relation embryology CTscan Davidoff MD 28994 28995 28996 28997 28998 28999 MRI Ashley Davidoff MD TheCommonVein.net
Tetralogy Type – Subaortic VSD – partial resorption of conus
CT angiogram image, and pathologic specimen of anatomy in ?tetralogy type.? Computed tomography angiogram, oblique image: CT angiography demonstrates both great arteries arising from the right ventricle, with conal septum separating the aorta and the pulmonary artery. RA, right atrium; Ao, aorta; PA, pulmonary artery; CS, conal septum; RV, right ventricle. E: Pathologic specimen: The VSD is bounded by the underside of the aortic valve and cradled in the arms of the septomarginal trabeculations. The pulmonary artery is walled off by infundibular muscle. Asterisks, borders of the VSD; white arrow, coronary artery orifice; black arrow, PMC, papillary muscle of the conus; Ao, aorta; PA, pulmonary artery; TVAL, tricuspid valve anterior leaflet; TVSL, tricuspid valve septal leaflet; D courtesy of Frandics Chan, MD, PhD, Stanford University; E courtesy of Diane Spicer, BS, University of Florida.) Courtesy Double-Outlet Right Ventricle Gail E. Wright et al thoracic key.com
