Nicotine's affect on the cardiovascular system is tempory and has not been considered a serious health risk since the Surgeon generals 1964 Report on Smoking states as much.
"page 41
The habitual use of tobacco is related primarily to psychological and
social drives, reinforced and perpetuated by the pharmacological actions
of nicotine.
Social stimulation appears to play a major role in a young person’s early
and first experiments with smoking. No scientific evidence supports the
popular hypothesis that smoking among adolescents is an expression
rebellion against authority. Individual stress appears to be associated more
with fluctuations in the amount of smoking than with the prevalence of smoking.
The overwhelming evidence indicates that smoking-its beginning,
habituation, and occasional discontinuation-is to a very large extent psychologically
and socially determined.
Nicotine is rapidly changed in the body to relatively inactive substances
with low toxicity. The chronic toxicity of small doses of nicotine is low
in experimental animals. These two facts, when taken in conjunction with
the low mortality ratios of pipe and cigar smokers, indicate that the chronic
toxicity of nicotine in quantities absorbed from smoking and other methods
of tobacco use is very low and probably does not represent an important
health hazard. "
http://profiles.nlm.nih.gov/ps/access/nnbbmq.pdf