Andy Irons, a three-time world surfing champion from Hawaii, who died at 32 in a hotel room last November, succumbed to a combination of a heart attack and drugs in his system, according to an autopsy report.

The presence of drugs confirmed rumors that dogged Irons during his surfing career. After winning championships from 2002 through 2004, and cementing his reputation as one of the greatest competitive surfers, Irons baffled the surfing world with erratic behavior. He abruptly quit the 2008 tour, and sat out the 2009 season before making a comeback in 2010.

The autopsy, provided to The New York Times on Wednesday by a publicist for Irons’s family, lists the primary cause of death as a heart attack related to coronary artery disease. The secondary cause is “acute mixed drug ingestion.”

Irons was found in his hotel room in Texas. In the room, the police discovered prescription bottles for Alprazolam, used to treat anxiety, and Zolpidem, a sleep aid, along with tablets containing methadone, a narcotic used to treat pain and opiate addiction. Toxicology tests showed Irons also had cocaine and methamphetamine in his system.