1. What is a ventricle? The Annals of Thoracic Surgery
Robert H Anderson, MD, Siew Yen Ho, PhD 
The Annals of Thoracic Surgery 
Volume 66, Issue 2, Pages (August 1998)
DOI: /S (98)

2. Fig 1
These illustrations, taken from the same heart, show how the morphologically right (a) and left (b) ventricles can simply be described as having inlet, apical trabecular, and outlet components. Note the marked difference in the patterning of the apical trabeculations in the two ventricles. (AV = atrioventricular; Pulm. = pulmonary.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

3. Fig 2
These illustrations show the coarsely trabeculated right ventricle (a) connected to both atriums (double inlet) and supporting both arterial trunks (double outlet). The apical trabecular component of the left ventricle (b), in posteroinferior position, forms an incomplete and rudimentary ventricle. (AV = atrioventricular; VSD = ventricular septal defect.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

4. Fig 3
These illustrations show double inlet to a dominant left ventricle (a). In this circumstance, it is the apical trabecular component of the right ventricle (b) that forms the basis of an incomplete and rudimentary ventricle in the anterosuperior position, in this instance with the pulmonary (Pulm.) trunk arising from the rudimentary ventricle (concordant ventriculoarterial connections). (AV = atrioventricular; VSD = ventricular septal defect.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

5. Fig 4
This illustration shows a truly solitary ventricle, which has very coarse trabeculations of indeterminate morphology throughout its apical component. (AV = atrioventricular; Pulm. = pulmonary.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

6. Fig 5
These pictures of the rudimentary and incomplete right ventricle from hearts with (a) double-inlet left ventricle and (b) tricuspid atresia show the remarkable similarity in morphology when the ventricles support the same arterial trunk (in these cases the aorta). (AV = atrioventricular; Pulm. = pulmonary; VSD = ventricular septal defect.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

7. Fig 6
This illustration shows tricuspid atresia produced by an inperforate valve interposing between the right atrium and the right ventricle. In this heart, the atrioventricular connections are biventricular and concordant and the right ventricle, although small, possesses all of its component parts. (TV = tricuspid valve.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )