Hello
Thanks for the query .
Your father blacked out , insulin dependent ,
low kidney function .
Echo & breathing tests are normal.
First of all I want to make clear that ECHO report is normal and your father didn't have any heart problem.
Now he is having
shortness of breath .
In my opinion your father blacked out due to
hypoglycemia ( low level of glucose ) as this is a very common cause of black out in old diabetic patient .
Hypertension or
Hypotension may be another cause of blackout.
Your one question is shortness of breath .
This breathlessness may be due to allergy as this is very common cause and only physical finding are any indication ( there present whistling sound, rales , mild dry cough ).
Last one reason may be anemia or lack of stamina .
In my opinion consult one more physician and get his opinion regarding , anemia , hypertension , hypotension , blood sugar level as well physical condition of patient.
Good luck.
Dr. HET