Perez died at his home in the Dominican Republic at the age of 44.
It appeared that Perez had fallen from a ladder, pending the report from the medical examiner.
Perez made his major league debut in 1998. He earned his lone trip to the All-Star Game in 2001 after being traded to the Los Angeles Dodgers. Perez had a 15-10) record with a 3.00 ERA in 32 starts that season.
Perez was traded by the Dodgers to the Royals. The lefthanded pitcher joined the Washington Nationals on a minor league deal and was invited to spring training in 2008.
The Nationals elevated Perez to their opening day starter. It was the first game in Nationals Park and Perez was the first to throw a pitch.
Perez was released the following year after he failed to report to spring training.
Perez finished his career with a 73-82 record in 241 appearances, with a 912 strikeouts and a 4.56 earned-star rating.