Nattokinase was reported to cause arrhythmias in 3.3% of trial participants according to pub media.nih.gov article.
Unfortunately, I was one of the unlucky 3% and nattokinase caused my arrhythmia, I believe. I got worse day by day for a couple of weeks until I figured it out by way of research and elimination. I suggest you drop the nattokinase and see if your arrhythmia goes away.
Notice that one of the cures to arrhythmia is to avoid soy.
