While the various medical sources clearly agree that “smoking” causes (or is likely to cause) heart disease, I cannot seem to find a definitive opinion on whether nicotine, alone (outside of the context of smoking), causes heart disease.
Would a person who does not smoke but is addicted to the nicotine patch be at greater risk than a non-nicotine user for heart disease?
Clearly nicotine has certain effects (increases heart rate and blood pressure) that would seem to make the heart “work harder,” but then so does caffeine, and caffeine is not generally thought of as having a direct link to heart disease.
A friend of mine had a heart attack at the age of 48 last month. He was a heavy cigarette smoker, emphasis on was. He says that his doctors say that smoking does something to the blood vessels that causes plaque particles to cling to the walls of the vessels more readily than they would without smoking. Thus, smoking causes blockage.
There is some evidence that nicotine in and of itself does promote atherogenesis, which may be a big contributor to some atherosclerosis, or arterial blockage. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?holding=npg&cmd=Retrieve&db=PubMed&list_uids=9609804&dopt=Abstract
http://atvb.ahajournals.org/cgi/content/abstract/12/11/1305
So, maybe nicotine in and of itself, either inhaled or ingested, does contribute to the process.