As you may be learning, panic can cause heart arrhythmia because it raises your adrenaline. Worry about your heart can cause this and make your heart very irritable. Stay close to your doctor. Try to get a copy of your event monitor results and share it with us. We might be able to help you read it. When you say irregular rhythm, what kind of symptoms - skipped beats, fast beats, etc? It would be helpful to know. We are not doctors but all of us have some kind of arrhythmia, and a lot of it is benign like yours might be too.
Debbie
I answered you at the Disease community, but I hope more of you will provide an answer! :)