Carbs, particularly when their effect is not mitigated by proteins and other nutrients, are processed very rapidly by the body, which causes a spike
and a subsequent drop in blood
sugar.
And as low blood sugar is a leading cause of arrhythmia, overconsumption of carbohydrates can easily be linked to these problems. Don't cut out carbs altogether, because your body still needs them, and they can be consumed in a way that will make your heart happy.