Have a knot on one of my veins in my arm from sleeping on it months ago. My arm loses blood circulation quick whenever I'm sitting to long. I'm curious about this knot that has been here for months, my heart hurts sometimes from this.?

Ans. You need to see your doctor and get a proper diagnosis. Sounds like you have so much anxiety. Just get a diagnosis and treatment and move on .
Knot on vein. Likely caused by stasis and is an old clot in a superficial vein. If it bothers you, have is seen and sclerosed. It should not affect your heart. All the best.