Ozzy Osbourne died of a heart attack and had coronary artery disease in addition to suffering from Parkinson’s disease for years, his death certificate said.

Ozzy Osbourne, the heavy metal and reality television star, died of a heart attack and had suffered from coronary artery disease and Parkinson’s, according to a death certificate filed at a registry in London.

Osbourne, the legendary frontman of Black Sabbath and a pioneer of heavy metal, died July 22 at his home in Buckinghamshire, England.