iam 60yrs old been smoking for about 50 yrs. just started o2 at night a couple of months ago. iam beating myself up, I have to quit I put on the patch but I still smoke. at the age of 43 my first attack and big one it was. two stents then . at 47 2 more stents then at 51 emergency bypass widow maker was 96% blocked. luck out that time. then at 56 colon removed. when do you learn. when iam not on o2 iam at 86% o2 with o2 and cpap machine at 98%. will my lung heal if I quit smoking right now.