IMO it will depend upon your state of health, your level of endurance and the area in which you choose to work.
The first two you ideally should discuss with your Provider.
The first two will help determine where you may work.
If you have a low EF and tire easily, you may not be up to the physical demands of work in a busy unit.
No matter what department you work, you will be unable to accompany a patient into the MRI suite, which may pose an occasional problem (others will need to cover for you).
Again, your Provider (ideally your Cardiologist or Electrophysiologist) is more qualified to offer an opinion and guidance on this subject.
Remember, too, members on this site are unable and unqualified to offer any medical advice.