Heaviness in arms and legs with shortness of breath
I have "bouts" every few months that last a few days then go away...where I will be standing for a few minutes,,,then My arms and legs get very heavy, and I start getting short of breath. I can breathe...but I don't feel like I am getting the oxygen. This will last for several minutes, or until I sit down. What is this? Heart...thyroid...what? I am really scared.