For an individual stricken with cardio problems to the extent that they need aortic valve replacement to still be smoking is shocking. Physicians are in an extremely difficult position with respect to prescribing pain medication. While patients request such medication with great urgency, the physician can face serious practice altering issues for over prescribing pain medication both from licensing authorities and also from patients if foreseeable issues arise. I see no legal issues based simply on the information in the post. Driving a legal wedge between patient and physician will not advance your cause.
Your doctor has a perfect right to cut off a prescription for pain medication. It's for your comfort, not to save your life. He is trying to save your life and apparently has been unable to get it through your head otherwise that your smoking is liable to kill you. Stopping smoking is very hard, I know, but if you stop you may find that your back pain improves. Smoking is not only bad for your heart and lungs, but also for your back.
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