I saw Dr. James Utz, a Senior Pulmonologist at Mayo, for those symptoms, which had progressed insidiously over many years. I was flying in from the Boston area so I had to make multiple visits over time to get to see him. (Initially my local Rheumatologist wrote a referral letter to be seen by Rheumatology at the Mayo Clinic.) He asked the right questions and listened well. He referred me to the heart failure group. I failed the special cardio-pulmonary stress test they do. Dr. Margaret Redfield recommended the heart cath to definitively diagnosis this. I also had symptoms of edema in my lower legs with some pitting, edema in face and neck, and specifically severe pain intermittently below and beneath my left scapula, which I understand could be a referred pain from the heart muscle. I also participated in a study that Dr. Robert Frantz is directing. It is believed that my MCTD is the cause of the "stiffening." I wish I'd known about this a long time ago but grateful that I finally have answers now.