Welcome to the forum
@Dee-Cee
Among other heart problems I also suffer with AF, it can be associated with many things.
Previous heart attack/surgery, diabetes, high blood pressure, being overweight, stress, stimulants like coffee, smoking, alcohol, drugs, poor sleep. I have never been warned about a low carb diet. My Dr and the cardiologist are ok with my low carb way of life, in fact my cardiologist encouraged me to go low carb to get my sugar levels and weight down after the operation.
In the last 8 years of low carb the episodes of AF are greatly reduced I'm only troubled by it now if I over indulge in coffee or booze. There are probably other things that will trigger AF for you, we are all different after all but I think it would be a mistake to dismiss low carb with out giving it a try.