I would recommend you have a look at the 5-2 diet. I have been using it for about 4 years.
It requires you eat normally for 5 days and fast for 2 days. On the fasting days you eat only 600 calories.
I chose Monday and Thursday for my fast days.
I sometimes found that the day after the Thursday fast day I would have an afib event. This was a rare event though.
I have since changed to 900 calories without any problems.
Over the time I have been on the diet I have lost about 55 lbs (25kg) from 230 lbs (105kg) to 175lbs (80kg).
As a result my blood pressure has dropped to normal (120/80)
At present I have been afib free for three months.
I hope that helps
Colin