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OTRC: Sage Stallone: Cause of death - heart attack, not illegal drugs

Sage Stallone appears with his father Sylvester Stallone in a scene from the 1990 movie 'Rocky V.' / Sage Stallone appears in a 2007 photo posted on his official MySpace profile. (Metro-Goldwyn-Mayer Studios / myspace.com/sagestallone)

Sage Stallone, son of Sylvester Stallone, died of a heart attack, spurred by pre-existing heart disease, and did not have illegal drugs in his system when he was found dead last month, the Los Angeles County Coroner's Office says.

Sage Stallone passed away at age 36 on July 13 and was laid to rest at a private funeral a week later. He was found dead at his home near Los Angeles. Police had conducted a welfare check on his property after no one had heard from him for several days. Authorities said there were no signs of forced entry or any other criminal activity that would currently prompt a criminal investigation.

Following an autopsy, the Los Angeles County Coroner's Office on Thursday told OTRC.com's parent company, KABC Television, that Sage's death was determined to have occurred naturally and that the official cause was a heart attack spurred by a pre-existing heart condition called atherosclerotic coronary artery disease.

A toxicology report showed that he had no illegal drugs in his body, although a "sub-therapeutic" level of Hydrocodone was detected. The substance is used in pain medications such as Vicodin.

The full report is expected to be released next week. It was previously reported that Sage's family met with the Los Angeles County Coroner's Office on July 17, citing concerns about his health, namely that he may have been overmedicated.

Sage is the son of Sylvester Stallone and ex-wife Sasha Czack. They also have a son named Seargeoh. The actor also has three daughters with current wife Jennifer Flavin Stallone.

Sage appeared in his father's film "Rocky V" in 1990 as the son of Sylvester's famous character Rocky Balboa.

He went on to appear in other films like "Daylight," which also starred his father, "Chaos" and "Promises Written in Water." He also wrote and directed a 2006 short film called "Vic."

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