Hello and welcome to Healthcare Magic. Thanks for your query. Though Marijuana is known to have analgesic properties, still it may not be advisable to use it as a first-line pain killer after a major surgery such as an aortic valve replacement. The reasons are: - The analgesic properties are only mild and hence, it may not be able to control post-operative pain completely. Especially, in a cardiac surgery, pain control is very important because poorly controlled pain can inturn cause an increase in heart rate, blood pressure, etc. which may cause complications. - It is very difficult to reliably monitor the dose and frequency of the drug. There can be erratic drug levels and hence unpredictability in pain control and management. - Some studies have shown that marijuana by itself can cause adverse effects like increased heart rate and blood pressure, blood thinning and possiblly delayed wound healing. Though these effects are usually mild, still, in a delicate surgery like a cardiac surgery, these adverse effects have to be avoided. So, my opinion is that it is preferable to depend on prescription pain killers for post-operative pain management which are well established and reliable, than to try out marijuana. Moreover, decisions regarding medication have to be made only after consultation and approval of your operating surgeon, and so, I would suggest that you have a discussion about the pain management part with your surgeon. Wish you all the best. Regards, Dr. Jonas Sundarakumar Consultant Psychiatrist