Ryan O'Neal's cause of death officially revealed 2 weeks after death

SANTA MONICA, Calif. (WKRC) — Ryan O'Neal, who died on Dec. 8, has officially had his cause of death revealed.

The Oscar-nominated actor passed away peacefully at the age of 82, and according to a death certificate, he died of "congestive heart failure."

Along with his cause of death, other information was released detailing some of his medical history. It said that O'Neal had suffered from cardiomyopathy for years before his death.

According to the Cleveland Clinic, cardiomyopathy is a condition that "affects your heart muscle." "If you have cardiomyopathy, your heart can't efficiently pump blood to the rest of your body."

Also on his death certificate was information about where he passed and where he was buried. O'Neal passed at Saint John's Health Center and was buried at Piece Brothers Westwood Village Memorial Park & Mortuary.

"I feel great sorrow with my father's passing," said Tatum O'Neal, Ryan's daughter."He meant the world to me. I loved him very much and know he loved me too. I'll miss him forever and I feel very lucky that we ended on such good terms."

O'Neal's death was announced by his son Patrick in an Instagram post. In it he said that his dad "has always been my hero," and that he "passed away peacefully."

Ryan had four kids. His daughter Tatum and his son Griffin were born to Ryan and Joanna Moore. He had his son Patrick with Leigh Taylor-Young, and he had his youngest son, Redmond, with Farrah Fawcett.

O'Neal had a long history of health issues. He was diagnosed in 2001 with chronic leukemia and then in 2012 he was diagnosed with prostate cancer.

In a statement to PEOPLE in 2021, O'Neal said "I'm proud of them, I've survived them. I thought I was gone. And suddenly I come back. Not the same man I was, but I'm back."

Following his leukemia diagnosis, Ryan reconciliated with Fawcett. The pair were originally in a romantic relationship from about 1979 to 1997. Then, after reconciling, the pair stayed together until Fawcett's death in 2009.

Also from the 2021 interview with PEOPLE, Ryan said this about this legacy:

“Oh, I've had so many stories told about me that I don't even know what my legacy is,” he said.