Episode 36 of "House"
s02e14 Heartless

When Henry (guest star Howard Hesseman) experiences a seizure but is not aware of it while its happening, House takes on the case. The teams differential diagnosis points to a bacterial infection, but Henry suffers a heart attack before the treatment for his infection is able to work, prompting the need for a heart transplant. Racing to find a heart donor in time to treat Henry before the infection kills him, House finds an organ donor whos been declared unfit due to a mysterious illness. He deceptively approaches the husband of the deceased woman, surreptitiously questioning him for information about his wife, when all he wants is her heart. Faced with only one option, House and the team must race against time to diagnose the dead womans illness before they can attempt to use her heart to cure their dying patient.