Hello
Thank you for your query at DoctorSpring.com
The MRI report of yours says that the myocarditis has resolved completely without leaving behind any significant damage. The heart function is good as well. So you can do exercise as you like. The ECG is showing some minor abnormalities but they wouldn't interfere with your activities and may probably be normal for your age.
Feel free to discuss further queries,
Regards
Dr Vivek Mahajan
DM Cardiology