Don't read this unless you are deeply interested in congenital heart disease!
I was lucky to be a newly appointed consultant in Leeds at a time when the nomenclature of congenital heart disease was being refined by the clinicians and morphologists involved. In the UK, the segmental approach was argued through, and my first paper was to do with it. I think it is fair to say that the UK took a lead in this.
The segmental approach puts the prime emphasis on how the chambers and great vessels are connected. Space does not permit a full discussion of it and so I will use this case to illustrate some points in the expectation that you have done the background reading.
This is a two tier heart, in that the ventricles are best described in spatial terms as being one on top of the other. This description does not tell you what is connected to what, and is of little practical value.
Describing it in the segmental fashion, you will have to take it from me that the atria were in situs solitus (or "usual atrial arrangement" as the plain English group would prefer it), and the great veins were normally positioned and connected. On the left there is an injection into the morphologically left ventricle (mLV) through a catheter which has entered it via the right atrium. Being the mLV the valve from the RA is the mitral valve. The inlet portion of the mLV is superior and its apex is on the left of the cardiac mass. On the right is another injection, through a retrograde arterial catheter via the aortic valve, into the mRV. Because of a large VSD, contrast defines the upper part of the mLV as well as the whole of the morphologically right ventricle (mRV). Now the segmental classification says that the mLV comes from the right atrium and exits to the main pulmonary artery (MPA) as is clear from the angio in the RAO view. The mRV comes from the left atrium and exits to the aorta. So this is solitus atria, ventricular inversion and transposition of the great vessels, popularly called "congenitally corrected transposition" for short, This description immediately outlines the basic haemodynamics. The other deformities are described next, in this case a VSD. The positional anomalies present in this case are described last. This is not intended to diminish their significance to the surgeon, it is simply a more ordered and relevant way of describing the situation.
So we have described the ventricles as as inverted despite the fact that much of the mLV lies to the left of the mRV. I would contend that this type of positional problem is best described as "axial twist", which is a frequent observation in corrected transposition, this case being quite a severe degree of twist. If you look at the LAO views, everything is rotated clockwise, as is someone has taken hold of the cardiac apex and given it a clockwise wring. The tricuspid valve (white dotted circle) and mitral valve (black dotted circle) have twisted about 90 degrees and the ventricular apices have twisted almost 120. If you could see the atria they would be mildly rotated.
I hope this has give you some insight. It is an old angiogram and you will be investigating this sort of thing on echo, MRI of CT, but I think the angio is still an easy medium from which to appreciate the overall anatomy.