Chocolate in large amounts may trigger attacks. Chocolate contains a little caffeine, but also contains the structurally related theobromine, a milder cardiac stimulant. Requires large amounts, and few cookies or ice cream should not casue a-fib...but it is possible.
More likely are the following:
Extreme fatigue, emotional stress, severe infections, severe pain, and illegal drug use can trigger A-Fib. Low or high blood and tissue concentrations of minerals such as potassium, magnesium and calcium can trigger A-Fib. Thyroid problems (hyperthyroidism), lung disease, reactive hypoglycemia, viral infections, and smoking can trigger A-Fib. Smoking cigarettes raises the risk of developing A-Fib even if one stops smoking, possibly because past smoking leaves behind permanent fibrotic damage to the atrium which makes later A-Fib more likely.
Yes it can. In cocoa theres a drug called theobromine and this widens blood vessels and is a heart stimulant. You have to be careful of a-fib because it's the major cause of strokes. Perhaps you are sensitive to this compound.
I get some arrhythmias (mostly palpitations - heavy beats and some increased ectopics) if I eat too much chocolate. I can get away with a Dove Promise (not a whole Dove candy bar) or 2 Oreos but that's my limit. Shoot! I remember when I used to eat a dozen Oreos as a kid.
I don't think so, maybe the sugar did something, but I think it's more of a coincidence.