The cardiologist and pulmonologist both said it wasn't heart or lung related and to look elsewhere. After wasting a few months someone thought to do an image of my neck, where they finally saw my thyroid was enlarged. It was so big my trachea was being squeezed. A lot. Instead of my airway being 25mm wide (or 1 inch) like it should be, it was instead 2mm wide (less than 1/10 of an inch) and pushed way over to the right. General consensus among my doctors is that to be this size it has to have been growing slowly for years, like most of a decade.
After meeting with endocrinologist, an ENT, and finally a neck surgeon, I had it removed a couple of weeks ago. The difference was immediate. When I went under, I was breathing hard just from moving to the OR table. When I woke up, I could breathe. It was that simple.
Coincidentally, I was due to get a new machine, and insurance wanted a new sleep study. We did that last Friday night, ten days after the surgery. I did two sleep studies in 2017. AHI from one was 124, and the other was 103. The diagnostic AHI from the one I did last week was 27. My original prescribed pressure in 2017 was 19/24. The sleep doc titrated me to 10 this time, and I slept 5 hours at that pressure with an AHI of 0.9. Much lower pressure means fewer leaks, less pressure on the right side of my heart, easier sleeping - lots of benefits.
Even more interesting, my trachea is still stretched out. If I exhale really hard I can make it rattle back there, which really annoys the surgeon. He said it will retract to its normal size slowly and will firm up, at which point I might not have sleep apnea any more. I'm not often speechless but that rocked me back a bit. There is some chance that in the future I won't need a CPAP machine.
Don't scroll down unless you can handle a gross bloody thyroid pic. A normal thyroid is about 4.8cm wide. That thing was in my NECK.
