Richard Donner's death certificate unveiled the cause that claimed the his life.

This week, multiple news sources obtained the official death certificate of Donner.

His wife, producer Lauren Schuler Donner, and his business manager first confirmed the tragic news in July.

As stated in the document from the County of Los Angeles' Department of Public Health, the iconic director suffered from heart disease before succumbing due to heart failure.

The cardiopulmonary failure occurred due to the existence of his atherosclerotic cardiovascular disease.

The disease, which refers to the hardening of the arteries, occurs when plaque builds up inside a patient's arteries. Per the National Heart, Lung, and Blood Institute, plaque can be made of fat, calcium, and cholesterol found in the blood.

It can eventually cause strokes, peripheral vascular disease, and heart attack - the one Donner faced.

The same document mentioned that he was a film director for decades following his debut around the late 1950s.

Tribute For Richard Donner

Following his death, his former colleagues and film partners expressed their heartbreak through heartfelt statements.

Steven Spielberg, who wrote the adventure picture "The Goonies," remembered him as someone who had a powerful command of his movies.

"Being in his circle was akin to hanging out with your favorite coach, smartest professor, fiercest motivator, most endearing friend, staunchest ally, and - of course - the greatest Goonie of all. He was all kid. All heart. All the time," he said, as quoted by Deadline.

Meanwhile, Rene Russo thanked the director for giving him the chance to take a shot early on in his career. According to Russo, he initially did not want to join "Lethal Weapon 3" after the director heard him he was just a model.

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Although Donner did not want to see him, the actor visited him for his interview.

His fears turned into hope as he did not find the filmmaker intimidating during their first meeting. In fact, Donner reportedly unleashed his gentle spirit and put him at ease with his sense of humor.

"He told me 'you remind me of my wife. You're a lot like [producer] Lauren [Schuler Donner]. And I thought, that might be a good thing," he told Variety.

Before his death, Richard Donner worked on his final film as a director on the 2006 "16 Blocks." He and Lauren produced a number of films under their The Donners' Company including the X-Men franchise.

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