There are many things that could cause the heart to beat irregularly. There may be true arrhythmias from the atria or ventricles. There may be an imbalance in the body's chemistries, thyroid function, blood sugar, or it could be simply a matter of not drinking enough fluids and the standard recommendation is eight 8 ounce glasses of noncaffbinated fluid daily. One should also avoid decongestants, which could make the heart beat fast, chocolate, and caffeine products. If the palpitations continue it is wise to have a thorough evaluation.