Is there a non-drug herbal remedy for atrial fibrillation?

I’m a 59 year old male who’s heart goes in and out of atrial fibrillation (AF) several times per day but is in normal sinus rhythm (NSR) most of the time. This has been going on since 2001. The strongest anti-arrhythmia drugs (including amiodarone and dronedarone) are not effective any more. My cardiologist thinks that amiodarone works adequately and that my condition isn’t bad enough to have an ablation procedure (to correct the electric problem in the atria). I’ve exercised regularly vigorously and consistently since 1979, never smoked, drank booze or took other recreational drugs. My heart is healthy and strong with no disease associated with it. Also my body mass index is 21 (the same as it was in high school). I could whine about how AF is destroying my life but I’ll spare you. Thank you, Lon