I am post 2 years x3 CABG and was at dermatology yesterday for this exact symptom. While it is a minor symptom in my health journey, it is an aggravation. I was told to use Sarnoff, they could inject steroid into the scar or a cosmetic laser procedure costing $1000. The explanation was nerves. Yesterday I had injections in my SI joints, which required laying on my stomach. My chest was hurting later. Should have insisted on pillow to lay on.