I smoked for almost 40 years and stopped in February 2006 when I had my first heart attack. I was fitted with 5 stents but unfortunately the damage smoking did to me caused me to have another 2 heart attacks in 2009. I needed a quadruple bypass operation which has thankfully pretty much restored my health. I'm posting this to try to persuade people not to make the mistake I did by thinking it will never happen to them.
No matter how hard it is to stop while you're healthy, it's much better than waiting till you have no choice.