A few possibilities. Most SVT ("supraventricular tachycardia") episodes are unrelated to diet. There's an inherent abnormality in the way electricity is initiated or conducted in the heart. Occasionally, it can be set off by caffeine or alcohol, though this is much less common than you might think. Rarely, acid reflux can be a trigger for svt; in these patients, any food causing heartburn may be a culprit.
Trigger Foods. Svt or supraventricular tachycardia is a rapid heart rhythm. Some foods such as caffeine and chocolate can aggravate the dysrhythmia. Allergies to certain foods can increase Adrenalin in your body and predispose to svt. Over the counter medicine such as pseudophed will also tend to exacerbate the rhythm disturbance.