The Republican former Kentucky House speaker was hospitalized just days after stepping down over sexual harassment claims.
Jeff Hoover is being treated for an unspecified heart issue at a hospital near his home, reported the Associated Press.
The 57-year-old Hoover admitted he was among four lawmakers who settled a sexual harassment allegation out of court with a staff member for the House Republican Caucus.
He admits to sending inappropriate texts to the staffer but insists they were consensual.
Hoover was elected House speaker in January, and was the first Republican to hold the position in nearly a century.
The veteran lawmaker, who has served 20 years in the statehouse, said last year that he had been diagnosed with diabetes, like his father, Welby Hoover -- who died in 1986 shortly after he was elected to the House of Representatives.