What can be the cause of heart palpitations and weird veins spasms?

See UR MD: R the palpitations associated with rapid hear rate or not, does it happen during exercise or not, do you feel dizzy and clammy and short of breath? The best would be to be examined especially during a similar episode by a an md. It can be from anxiety to what is called svt or supra ventricular tachycardia, or sinus tachycardia due to anemia o excessive thyroid function. See an md!