I did 7,5 hours multisport event. With the average HR 140. Checked all blood chemistry before- was all OK. I had a lot of small holes on the last check up 6 months ago, with no outside symptoms. Feel perfect after workout, continue to train and get ready for Iron Man in 2018.
Yes- strict MS Diet+VitD+hemp oil treatment+ flax seed oil on the menu constantly.

But yes, at least in my case it looks possible!
Feeling excited and hopeful