See internet "vagus manuevers for arrhythems" or try "home remedies for arrhythems"

What works best for me:
A deep, forceful (fake) cough, or

1) Sit down, relax, inhale deeply for a count of 4
2) Hold you breath for a count of 7
3) Exhale to a count of 8
4) Repeat 4 times.

Good luck!