Berry, 25, felt a discomfort near his chest following the team's Thursday game against Oakland, and underwent tests in Kansas City where the initial diagnosis was made, according to the Kansas City Star.
"Right now he needs to be a beast, and he'll attack this . . . I think it will be a positive result when it's all said and done," Head Coach Andy Reid said at a press conference on Monday.
The Chiefs organization placed Berry on the non-football injury list, ending Berry's season. The safety released a statement regarding the diagnosis.
- "I am truly thankful for all of the support from family, friends, coaches, teammates and the entire Chiefs kingdom. At first I was in shock with the diagnosis on Saturday and did not even want to miss a game, but I understand that right now I have to concentrate on a new opponent. I have great confidence in the doctors and the plan they are going to put in place for me to win this fight. I believe that I am in God's hands and I have great peace in that.
I know my coaches and teammates will hold things down here the rest of the season and until I am back running out of the tunnel at Arrowhead. I am so thankful and appreciative of being a part of this franchise and playing in front of the best fans in the NFL. I will be back!"
Twitter users showed their support for Berry.
Berry will be evaluated the next few days at Emory University in Atlanta. Drafted in 2010, Berry has played his entire career with the Chiefs, and is a three-time Pro Bowler.