If you want to know more, you have no choice but to go back to your doctor with a notepad and list of questions. Only your doctor has examined you and has your history and enough information to explain what is going on.
if your EF in echo is 25 percent you must go to doctor and follow your problem,normal EF is between 55-75 %,and under 30% is very important problem,see your doctor and discuss with him,good luck