Rodney King -- Autopsy Report Prompts Family Health Scare

Rodney King's family believes R.K.'s autopsy report contains a key piece of information about Rodney's health that could save their own lives ... and it centers around his heart.

A member of the King family tells TMZ ... the coroner explained how Rodney suffered from an enlarged heart before his death ... a condition that has grave consequences if left untreated.

While Rodney's heart condition wasn't the main cause of his death (see: drowning, cocaine, PCP, alcohol) multiple members of his family view the discovery of King's cardiomegaly as a "wake up call" to get themselves checked out.

One family member who didn't want to be identified tells us, "I never knew he had heart trouble. I am worried that I could be at risk as well and I'm making a doctor's appointment next week."