Hearts with Single-Ventricle Physiology

With Kevin S. Roman

Pathologic conditions that cause single-ventricle physiology (Fig. 26.1):
- • Double-inlet left ventricle (so-called single left ventricle)
- • Double-inlet right ventricle (so-called single right ventricle)
- • Double-inlet indeterminate ventricle (so-called common ventricle)
- • Absent right atrioventricular connection is synonymous with tricuspid atresia when the absent connection involves the morphologic right ventricle.
- • Absent left atrioventricular connection
- • Also included are the following:
  - – Hypoplastic right heart with pulmonary atresia or critical stenosis (Chapter 17)
  - – Hypoplastic left heart syndrome (Chapter 22)
  - – Unbalanced atrioventricular septal defects
In most cases there are two ventricular chambers present, with one well formed and a second rudimentary, although on occasion there are two equally dominant ventricles.
Atrioventricular valves guarding the inlet can be two separate valves, one patent valve with one atretic valve or a common valve.
Tricuspid atresia: often associated with left juxtaposition of the atrial appendages
Great artery origins vary and may be concordant, discordant, or double outlet from the main or rudimentary chamber
Great artery connections may be patent or obstructed