Simpson collapsed on the floor during Purdue's game at Nebraska, but returned to the bench quickly. Tests were run all last week, and confirmed it's HCM.
"Obviously, this is very tough and upsetting news to take," Purdue coach Matt Painter said in a statement. "You never want to see a young athlete's career end in a fashion like this. Jay had a very bright future in our program and we are disappointed that he will not be able to continue his basketball career. We are very fortunate that our doctors were able to detect this condition early, which will enable Jay to live a long and healthy life."
HCM is what led to the death of Hank Gathers, Reggie Lewis, Kevin Duckworth and Jason Collier. Thankfully, Simpson's condition was detected early.
"HCM is a disease which causes structural abnormalities to the heart and may lead to sudden death in young exercising athletes," Purdue team doctor Greg Rowdon said in a statement. It's discovery precludes the participation in competitive sports."
Simpson is expected to graduate in May of 2016, and will remain on scholarship at Purdue.