ET is hearing that Lamar Odom suffered a heart attack on Tuesday night and was placed into a medically induced coma.
A source close to Odom tells ET that the former NBA pro had some organ failure after he was found unresponsive at the Love Ranch brothel in Crystal, Nevada. While his condition has improved, our source says "it is still dire."
ET can confirm that the former NBA pro's father, Joe, arrived at Sunrise Hospital in Las Vegas, Nevada, where Odom is in critical condition, and Odom's two children are expected later today. Odom's ex, Khloe Kardashian, has been by his side since first arriving on Tuesday night. Her sister, Kim, and mother, Kris Jenner, are there as well.
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The Kardashian-Jenner family are "praying for a miracle to happen."
"They are devastated. They have tried so hard to help Lamar with his issues and it breaks their hearts that he could lose this battle," a source close to the family told ET. "The entire family is pulling for Lamar to make it through this."
As for the Keeping Up With the Kardashians cameras, ET confirms that the reality show is not rolling while the family is at Sunrise.
Meanwhile, entertainment reporter Ken Baker says Odom's doctors are treating the 35-year-old athlete's health condition as a drug overdose. When speaking to E! News, Baker said a source inside the hospital told him that "drugs were found in [Odom's] system," including opiates.
Baker's source reportedly added that doctors think Odom suffered from an ischemic stroke, where blood circulation is cut off from the brain. This condition can occur with excessive cocaine and/or crack cocaine use, but this has not been confirmed to be the case for Odom.
MORE: Khloe Kardashian at Lamar Odom's Bedside as Family Gathers at Las Vegas Hospital
"So, likely there's brain damage, but they're not sure how much," Baker's source reportedly said. "Virtually every drug imaginable was found in his system."
MORE: Lamar Odom's Friends and Former Teammates Offer Prayers and Support: 'He's a Fighter'
When ET spoke with brothel owner Dennis Hof, he did not think drugs were at play. "The police looked through his things and they didn't tell us they found anything," Hof said. "The girls that were hanging out with him didn't see any use of any illegal drugs at all."
A source at the brothel where Odom was found also revealed to ET that he was staying in the establishment's High Roller Suite, which is considered Hof's private lair. The stated price for this suite starts at $10,000 a night.
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ET was told that Odom made a reservation at the Love Ranch. A car service was arranged to pick him up, and he was at the brothel for four days.
"He looked terrible," Hof told ET of Odom's appearance. "He looked like a guy who was really sick and needed to be rushed to an ER immediately."