That is a swelling of the lining of the heart. Sent me to the ER lol. I had no idea what was going on but after a few heart attacks I figured it was just another one. Still have remnants of it. Unlike you my arteries are not clear. And to make it worse I have an autoimmune thing going on that is causing them to close even more. I did have a stent put in about a year and a half ago but studies on those things are mixed. I urged the doc not to put one in but he strongly suggested it.
I am one of those lucky people who create their own bad cholesterol and do not create good cholesterol. Lol... inherited.
Congrats on your good news.