Photopenia in the septum indicates images of the suptum (wall that separates right and left heart chambers) has less density at the location designated. It can mean the presence of ischemia (lack of blood flow) with exertion but goes away with rest.
Q: "Also there is no right ventricular deposition".
>>>>Sometimes there are fat deposits within the heart tissues and that results in an enlargement of the ventricle....no problem seen, and there is no left ventricular dilatation with stress.
There doesn't appear to be any heart condition that would cause shortness of breath. If there is heart related shortness of breath almost always there would be an enlargement of the left ventricle. Symptoms do indicate you have a condition referred to medically as hypoxia (low oxygen level within tissues) that has many causes such as anemia, respiratory issues, etc, and that could/would cause shortness of breath.
I hope this helps and if you have any further questions or comments you are welcome to respond. Take care and thanks for the question.