I used to be a smoker until I had triple coronary bypass surgery July 27, 2011. I was told afterwards by a doctor that if I continued to smoke after the surgery (I have quit smoking tobacco totally since the operation and will never resume tobacco smoking again) that the new arteries around my heart would suffer a spasming and start to shrink, causing blockages again. This even applied to being exposed to second hand smoke. I am an ocassional marijuana user, though not since the surgery. I was told that this spasming and shrinkage also applied in regards to smoking marijuana. Is this true or was this an attempt by a very anti-marijuana, anti-smoking doctor to keep me from smoking pot again? What if I were to use a vaporizer, so that I am not taking in the harmful by-products of actually combusting the pot ? Incidentally, I have no heart damage from the blockage that I had repaired, am a 53 year old physically active male, and have no desire to undergo another bypass, although heart disease is a definite history with the men from my fathers side of the family. Grandfather, 2 great uncles, 1 uncle all dies of heart related deaths (stroke and heart attacks), 1 uncle has also had a quadruple bypass, and my father died of a sudden massive heart attack at the age of 68. I thank you for any answers you may have as I am honestly interested in ocassional marijuana smoking in the future.