Good morning, I'm late in joining this discussion, but I find it very interesting. I was very recently diagnosed with SFN, and while I do have some peripheral issues, mine are mostly autonomic. For more than a year, I've had intermittent dull to very sharp pain under my left breast very near the sternum. I've even gone to the ER a few times certain that I was having a heart attack. I've had multiple heart workups with no significant findings. I've always had asthma, and it's been suggested that it's an allergic or panic reaction, neither of which make sense in the context. Sometimes it just aches and others it's so sharp that it takes my breath away. Now that you mention it, I also wonder if this was one of the early signs of my SFN (?SFMAD). My neurologist keeps telling me that SFN can cause such a wide range of symptoms that almost anything is possible. Any other thoughts, experience or info that anyone has would be greatly appreciated.