A non-functional heart murmur and no other cardiac disease does not increase the already small risk of anesthesia. Do be sure to inform your surgeon and your anesthesia provider anyway.
Heart murmers come in all shapes and sizes. Fortunately, the majority of murmers require no treatment at all. Though you will need to undergo anesthesia for your revision rhinoplasty, in a 30 year old patient there is an extremely remote chance of any adverse cardiac issue taking place. Most importantly is that you trust your family doctor and I am certain that they would be very cautious and send you for further testing if they even had a suspiscion of something more significant with your cardiac status.
An "innocent" murmur, by definition, is not a medical problem, and would pose no additional risk. The question becomes is the murmur truly "innocent?"
In a 30 year old healthy person, statistically, the answer is "probably." A cardiologist can help confirm, and a consultation would be appropriate.
There are several types of heart murmurs and some are referred to as 'physiologic' or 'incidental', meaning they pose no risk to you or your heart. Some heart murmurs require that you take an antibiotic one hour before surgery or dental work. My advice would be to not let the discovery of this heart murmur deter your plans to undergo a revision rhinoplasty, but definitely see a cardiologist first to make sure it's ok to proceed. Have your heart checked by an expert so that you are clear to proceed with the revision rhinoplasty, or any other procedure you might need in the future. Play it safe.
You need to see your cardiologist. If your cardiologist says it is nothing then he can give clearance for surgery. Best of luck.
If you've been told not to worry about your heart murmur you probably will be able to have your surgery without additional risk. HOWEVER, you need to get clearance from your cardiologist before your revision rhinoplasty.
There are many different reasons heart murmurs occur, so It is best to be checked out by a cardiologist to get clearance prior to general anesthesia for the rhinoplasty procedure.
Without knowing what kind of heart murmur you have I cannot tell you whether surgery is safe. It is likely safe as most heart murmurs are minor and do not prohibit you from receiving general anesthesia. For certain murmurs, you will need to be on antibiotics prior to surgery. If your family doctor found the murmur I would also pose the question with your family doctor.