Hi, I can relate to this so heavily. To answer your main question: don't get a stent. I've been told by multiple surgeons in Boston that it is borderline medical malpractice. With all the movement in that area off, the stent can break off and act like a more-lethal blood clot (PE, stroke). If you want to try and clear out your vein, angioplasty is an option. The relief can be lasting, but I've been told it's pretty temporary for athletes.
It sounds like you have post thrombotic syndrome, congrats, welcome to the club. I promise it's not all bad.
Let me give some context. I rock climbed (or trained) roughly 15+ hours per week beginning in 2014 at age 17. In 2019, I woke up and my arm was wicked swollen and unusable. An ultrasound showed a huge subclavian clot, it was removed within the week, the rib was taken out within 2 weeks, and I had just as many symptoms pre-op and post-op. Giant arm, barely usable, huge veins on my deltoids, pinching in my armpit. Based on photos and symptoms, I believe I had the clot for 1 year.
I also have giant collateral veins, and you should be extremely proud and thankful for yours. They not only saved your arm, they now are the primary blood movers. In fact, since you had a clot for so long (and young+active) your body had a lot of time to develop compensatory collateral veins. This is a silver lining to having a clot in your vein for so long.
My arm has stabilized, though I still have post thrombotic symptoms. My subclavian vein is narrowed (per ultrasound), but my collaterals are cranking. Blood flow back to my heart is sufficient in that arm. I have weird, lasting neck pain after the surgery, though. Sometimes I wear an arm sleeve for the swelling.
My recommendation is to ask multiple doctors about chronic DVT / post thrombatic syndrome, consider angioplasty, trust in your collateral veins to keep your arm healthy as time passes. You might need a significant amount of "rest" from intensely competitive sports. Not complete rest, as collateral veins improve function with activity.
Here's where I double relate: I'm 25, I now have vein compression on my left side (no clot though), but I am likely to clot if I keep climbing. I'm taking my first long break since right-side surgery to figure myself out a bit more. Identifying with a sport isn't great in the longterm, as the body gets ill, especially with age. I'm sorry you had to confront this so early in your teens, but I trust it is making you a wiser person. As for me, I can still do a lot with my left arm without pinching the vein (deadlifting, hiking), so I'm content on a break from "my" sport. I will likely get the rib removal surgery if I ever clot. I will return to light climbing once COVID no longer affects hospitals. There are plenty of studies on patients who get the clot removed, don't get rib surgery, but do well. Perhaps that will happen to me if I return to climbing.
Yeah I recommend [this one.])https://www.amazon.com/dp/B076B93ZP8?ref=ppx_pop_mob_ap_share). I used to wear it daily, now only once or twice a week. I switch between L & XL. It’s pretty damn tight but comfortable with the right fit.