First thing's first: relax. Deep breath. It seems like a mess now but it probably isn't as bad as you think. The FAA is pretty progressive with cardiac issues. As the good Doctor before me said, you may have to jump through some hoops (but thats where AOPA or AMAS comes in handy). That being said, my first recommendation would be to contact AOPA or ALPA medical (AMAS) if you have the ability.
I would also demand to speak with your cardiologist (not a go between) or contact a different cardiologist and have your records reviewed by their office. If it's a rhythm issue, perhaps a referral to an electrophysiologist would be appropriate. Yes you may spend some dough, but better to rule out serious issues now.
I'm not sure what kind of abnormality was shown? Was it a Premature Ventricular Contraction (PVC), or Premature Atrial Contraction (PAC?) The FAA has steps to address these diagnoses. Take one step at a time, but take care of yourself first.