Jean-Marc Vallée cause of death revealed

New details have emerged about “Dallas Buyers Club” filmmaker Jean-Marc Vallée’s unexpected passing.

The 58-year-old director is believed to have died from a heart attack at his cabin outside Quebec City over Christmas, sources told Deadline.

The “Big Little Lies” filmmaker was prepping to host guests over the weekend, sources said, adding that it is likely he died Dec. 25 and was found the following morning.

Vallée was a health enthusiast, who abstained from drinking, worked out constantly and practiced Wim Hof’s extreme breathing methods, which involve holding one’s breath for long periods of time, often in frigid environments.

Jean-Marc Vallée passed away over the weekend at 58.
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Tributes poured in for the director Monday and many celebrities shared heartbroken condolences for their fallen friend.

“Spy” director Paul Feig tweeted, “My god, this is so unbelievably sad. What a huge loss. He was an incredibly talented filmmaker. Sending much love and condolences to his family. #RIPJeanMarc.”

“Big Little Lies” stars Shailene Woodley and Reese Witherspoon also paid tribute.

“I am in shock. Complete and utter shock,” began Woodley, 30, via her Instagram Stories. “My f–king god death is the worst. But I guess somehow I know you will turn it into a grand adventure … one for the books. One I can’t wait to read & to watch when my time comes.” 

The actress added, “It doesn’t make sense though dude. It doesn’t make sense. Maybe when we wake up tomorrow you’ll be there laughing saying it was just a satirical short film you made. That it’s not real.”

Jean-Marc Vallee
Vallee and the cast of “Big Little Lies,” Nicole Kidman, Zoe Kravitz, Reese Witherspoon, Laura Dern and Shailene Woodley.
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Witherspoon, 45, tweeted out, “My heart is broken. My friend. I love you.”

The Canadian Prime Minister Justin Trudeau, also wrote, “Jean-Marc Vallée’s passion for filmmaking and storytelling was unmatched – so too was his talent. Through his work and with his art, he left a mark in Quebec, across Canada, and around the world. My thoughts are with his family, friends, and fans as they mourn his sudden passing.”

The “Young Victoria” director is survived by his two sons, Alex and Émile, as well as siblings Marie-Josée Vallée, Stéphane Tousignant and Gérald Vallée.