Main»DORV Amp Other Malpositions

DORV Amp Other Malpositions

DORV and Other Malposition Anomalies

1. Definition

A.Double outlet right ventricle
1) Both great arteries arise wholly or in large part from right ventricle
2) Ventricular septal defect - one great artery may overlie VSD (50% rule)
B.Classification controversy
1) Tetralogy of Fallot
2) Taussig-Bing heart

2. Ventricular Septal Defect

A. Usually large
B. Subaortic (simple DORV)
C. Subpulmonary (Taussig-Bing heart)
D. Doubly committed
E. Non committed

3. Other Anatomic Features

A. Infundibulum
1) Double conus in 3/4 with sub-Aortic VSD
2) Double or single conus equal with subPA VSD
B. Great arteries
1) Usual position in most
2) Side-by-side less common
3) D or L TGA rare
C. Pulmonary stenosis
1) Common with sub-Aortic VSD (infundibular)
2) Uncommon with subPA VSD
3) Coronary artery pattern follows great vessels

4. Clinical Features

A. Presentation: large VSD, high pulmonary flow, not cyanotic, but decreased SaO2
B. Streaming brings high SaO2 blood to Ao (subAo VSD) or high flow to PA(subPA VSD)
C. Cyanosis related to PS or rapid onset PVD (subPA VSD)
D. Natural history similar to large VSD or TET

5. Operations

A. DORV with subaortic VSD
1) Intraventricular tunnel VSD to Ao
2) Low risk
3) Age 6 months
4) Extracardiac conduit RV to PA for PS
B. DORV with subpulmonary VSD (Taussig-Bing Heart)
1) Close VSD to PA plus arterial switch procedure
2) Complex intraventricular tunnel VSD to Ao with infundibular resection
3) Atrial switch no longer used
C DORV with non-committed VSD
1) Fontan procedure
2) Complex intraventricular tunnel to Ao or PA

6. Atrial Isomerism

A. Definition
1) Atrial isomerism means both atria are similar - bilateral right or bilateral left
2) A subset of situs ambiguous - asymmetric structures tend to be symmetric
B. Viscera heterotaxy
1) Asplenia syndrome: bilateral atrial, thoracic and abdominal RIGHT sidedness
2) Polysplenia syndrome: bilateral atrial, thoracic and abdominal LEFT sidedness
3) Thoracic situs best indicated by bronchial anatomy

7. Morphology

A. Conduction System
1) Right (asplenia) - bilateral SA and AV nodes, NSR
2) Left (polysplenia) - SA node hypoplastic, CHB 10%
B. Systemic venous return
1) Right - commonly anomalous
2) Left - 20% anomalous
C. Pulmonary venous return
1) Right - TAPVC 20%
2) Left - Cor Triatriatum common, TAPVC rare

8.Atrioventricular connection ambiguous, 25% univentricular

A. Great arteries - DORV or TGA 50-85%
B. Common atrium - AV canal defect 50-95%
C. VSD nearly always present
D. Pulmonary stenosis or atresia
1) Right - common
2) Left - uncommon

9. Treatment

A. Natural history
1) Right - asplenia associated pneumococcal infections
2) Left - complete heart block, biliary atresia
B. Operations
1) Complex atrial baffle (venous anomaly + AV canal) Fontan (pulmonary atresia)
2) Palliative shunts and PA banding

10. Positional Anomalies of Conotruncus