What helped my irregular heartbeats was getting proper ca/mg for my body (currently need 6:1). Also taurine and coq10 also feed the heart.
Getting circadian rhythm in sync was also important (if my sleep cycle is messed up my heart may skip a beat) - this is most likely dysautomnia which certainly can arise due to wacky thyroid/adrenals/pituitary (correct hormone output is very important to maintain proper nervous system function).
Also with all this Iodine talk, I read that Iodine is very important for calcium utilization (parathyroid related) - it's possible that by healing the glands, electrical impulses to the heart may be normalized