Black Sabbath frontman Ozzy Osbourne died July 22nd, just weeks after successfully pulling off the stuff-of-legends Back to the Beginning concert with the original lineup of the group. A death certificate now reveals Osbourne's cause of death as cardiac arrest – a heart attack.

The 76-year-old rock legend's certificate further notes that Osbourne passed away of "(b) Acute myocardial infarction (c) Coronary artery disease and Parkinson's disease with autonomic dysfunction (Joint Causes)." Osbourne's daughter, Aimee, submitted the document to the New York Times on August 5th.

An air ambulance flew Osbourne from his home to Harefield Hospital, in the London suburb of Uxbridge, on the day of his death. Thames Valley Air Ambulance noted that it was "dispatched to provide advanced critical care."

Osbourne was known to have been suffering from a variant of Parkinson's, with the singer's ability to walk compromised as a result. He performed in a throne during the Back to the Beginning event.