Filmmaker and actor Kevin Smith has shared on social media that he suffered a "massive heart attack" on Sunday, Feb. 25. He was found to have had a blocked left anterior descending (LAD) artery, which is a fatal condition in majority of cases.

Smith tweeted a photo of himself in a hospital gown, with a caption saying that he survived a heart attack and a deadly blockage in a major artery. He reportedly felt ill after a comedy show on Sunday night, opting not to do a second show to go to the hospital.

Smith is known for directing, writing, producing, and acting in the award-winning 1994 film "Clerks." He also wrote and directed films such as "Dogma," "Jersey Girl," and "Red State."

The New York Daily News reported that Smith was due to perform at two shows that Sunday, one at 6 p.m. and the other at 9 p.m. Smith cancelled his second taping for his stand-up comedy show, "Kevin Smith Live!"

"The Doctor who saved my life told me I had 100% blockage of my LAD artery (aka "the Widow-Maker")," Smith wrote in his tweet. "If I hadn't canceled show 2 to go to the hospital, I would've died tonight."

The LAD artery is considered to be the most important of the three arteries in the heart, because it pumps blood to a larger area of the heart than the two other arteries. It has earned the moniker "widow-maker" because the heart attacks it causes have high fatality rates.

According to an Instagram post by Smith, death was the thing he most terrified of in his life. He also wrote that his father died after suffering a heart attack himself.

"When the time came, I never imagined I'd ever be able to die with dignity - I assumed I'd die screaming, like my Dad (who lost his life to a massive heart attack)," Smith wrote in his post. However, he continued that he felt calm as he contemplated the possibility of his death because he felt that he has had a great life.

Smith also mentioned that he will be making some changes to his lifestyle after this ordeal, writing that he may become vegan.