increased heart rate is not a risk, it happens when you run, when you fuck, even when you sleep. it's normal. so smoking is not a natural reason for a raised heartrate, but it certainly is a common thing to happen.

this isn't me saying that it's healthy for your heart to smoke, but if alls your worried about is an elevated heartbeat, then you're fine.. it causes nothing more than anxiety & paranoia (that happens to the best smokers)