Hart posted a picture from his hospital visit on Instagram.
"So happy to see my brother @nickcannon getting back to himself. Nothing but love for you man..... #GetWellNick #Ncredible," the comedian wrote.
Cannon, 36, expressed his gratitude for Hart, 37, and all of his fans on social media.
"Man, so many loving strong vibrations came to visit me in the hospital today! Thank you to EVERYONE for all the gifts, messages, comments, the time, the love and the prayers... I'm getting there!!! And once I'm back... It's about to be #Ncredible," he wrote.