Rapid heart beat at rest reason to call doc?

Depends: It depends on what you mean by rapid and if it is sustained - some people run a little fast (100-120) and this can be chronic - certainly if you are having rapid heart rates of 150 beats or more per minute with shortness of breath and / or chest pain you should go to the er. If you are just running a little fast then you should make an appointment to see your doctor for checkup.

Yes: Your doc will figure out whether it is physiological or pathological and whether it needs any intervention.

Maybe, maybe not: Normal hr at rest is around 60-100 bmp. Sometime emotional excitement, even when you are resting, it can be a bit fast. Also, if you have taken some cold medicine/decongestants, or too much caffeine/energy drinks, or all of the above together can really speed up your heart. Asthma medicine--albuterol etc..Can increase hr. So, if u have no reason for fast hr, consult doc. Good luck.