DORV

Question 1

Embryology

Answer 1

• Considered in spectrum of conotruncal defects
  o Both GA arise from RV
  o Concordant AV connections
  o Typically outlet VSD: under GA w/ < conus
• Rotational defect: GA alignment determined by amount of conus beneath valve
  o >conus → superior and anterior position
  o Normally PA
  o Spectrum:
   No Ao conus = TOF
   Bilat conus = DORV
   No PA conus = TGA

Question 2

Most common associated lesion

Answer 2

PS

Question 3

Gross exam

Answer 3

• Both PA and Ao exit from RV
  o Degree of Ao positioning over RV: definition depend on authors
   >50% over RV
   >90% over RV
   Loss of AoV-MV continuity
• Relation of great arteries
  o Normally related → Ao caudal and to the R of PA
  o Ao // PA, originate to the R and cranially to PV
  o Ao cranial, PA caudal and to the R
• Malalignment VSD → outflow for LV
  o Usually large, not restrictive
  o Beneath AoV or PV

Question 4

Physiology types

Answer 4

• DORV w subaortic VSD and PS → TOF type
• DORV w subaortic VSD w/o PS → VSD type
• DORV w subpulmonic VSD w/o PS → TGA type
• DORV w non committed VSD

Question 5

DORV w non committed VSD physiology

Answer 5

o Equal bilateral conus: VSD not related to 1 GA

Question 6

DORV w subpulmonic VSD w/o PS physiology

Answer 6

TGA type

o Ao anterior, > conus
o Most blood from LV → VSD → PA
o Most blood from RV → Ao

Question 7

DORV w subaortic VSD w/o PS

Answer 7

VSD type

o PA conus slightly > Ao, bilateral conus
o Large VSD: L → R shunting → pulmonary overcirculation

Question 8

DORV w subaortic VSD and PS

Answer 8

TOF type

o PA anterior, hypoplastic
 Degree of PS determines pathophys
o Ao overriding IVS >50%
 LV → VSD → Ao

Question 9

C/s depend on

Answer 9

magnitude of pulmonary blood flow
o Cyanosis: based on origin of Ao
 ↑ severity with PS or PH (↑ resistance to flow)
 Related to insufficient pulmonary flow
o L CHF signs
o Lethargy
o Sudden death
o Retarded growth

• Physiology c/s → simulate TOF and TGA
  o Large VSD → equalization of RV and LV systolic P

Question 10

PE

Answer 10

loud holosystolic murmur

Question 11

ECG

Answer 11

• R axis deviation
• Ventricular arrhythmias

Question 12

CTX

Answer 12

• R sided cardiomegaly
• Pulmonary overcirculation (unless PS or PH) → pulmonary tortuosity/hyperperfusion
  o Pathway of least resistance for outflow

Question 13

Echo

Answer 13

• VSD
  o No flow disturbance on color flow since large and non restrictive
• Absence of AoV-MV continuity
• Narrow subpulmonic pathway if associated with PS/PA hypoplasia
• RV associated with both GA
• Ao//PA

Question 14

Natural hx

Answer 14

• L to R shunting → L CHF: common early in life
• R to L shunting
  o Development of pulmonary disease and PH later in life
  o PS
  o Congenital PH
• Prognosis is guarded to poor
  o Sudden death early in life reported