Dog the Bounty Hunter star Duane "Dog" Chapman has been diagnosed with a "life-threatening" heart condition, just three months after his wife, Beth, died following a battle with cancer.

People shared a clip of an upcoming episode of The Dr. Oz Show that is scheduled to air on Monday (Sept. 30), in which the famed physician gives his friend the news that he has a pulmonary embolism.

“You’re a ticking time bomb,” Dr. Oz says in the clip above. “You’re not going to be here with the heart the way it is right now. Fear of death is normal. I’m surprised you don’t fear death when you’re chasing after convicts. But when you run away from doctor, that means you have to do your own doctoring.”

According to the Mayo Clinic, a pulmonary embolism is "a blockage in one of the pulmonary arteries in your lungs." It affects the heart because "your heart must work harder to push blood through those vessels. This increases the blood pressure within these vessels and the right side of the heart, which can weaken your heart."

Beth Chapman died on June 26 following a two-year cancer battle. She was 51. Dr. Oz tells People that Duane Chapman has been neglecting his health in her absence.

“[Duane] was fearful,” he says. “Beth had been his north star. She was the one that would go with him and keep him balanced so he could deal with these things. Losing her took away his biggest support.”

“I said, ‘What would Beth do,'" Dr. Oz states. "'What would she say to you? I don’t think she’d be happy with what you’re doing. 'You’re throwing away your life, you’re throwing away your ability to parent your kids. You have to man up.’ That’s what she would say."

That was enough to convince 66-year-old Chapman, who suffered a "heart emergency" just two weeks ago. He has altered his diet, begun taking blood thinners and is working on breaking his smoking habit, and he tells People that despite some initial trepidation, he feels "encouraged" that he's back to "100 percent."

“I don’t want to die right now," he says. "I’m not afraid to die anymore, but I really didn’t care for awhile if something would happen. I do care now.”

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