Duane "Dog" Chapman says he couldn't breathe, so he called for his assistant to take him to the hospital last weekend. In a new interview, the reality television star suggests that the pain came from heartbreak.

"I think basically, I had a broken heart," Chapman tells KDVR-TV, a Fox station in Denver, Colo.

The 66-year-old describes what was sharp pain in his chest and breathing struggles — similar to what one might experience after running a few miles. Chapman's assistant took him to a hospital in nearby Castle Rock, Colo. on Monday (Sept. 16). Initial reports indicated it could have been a heart attack, but that was later refuted. Doctors aren't sure the cause of the heart or chest emergency, but more tests are scheduled for Thursday and Friday.

"It feels much better now," the reality star says, "And I'm going through some psychological things right now too, so that doesn't help."

The television station reports that three of Chapman's kids are staying with him, including two who came from Hawaii to be by his side. Physically, the Dog the Bounty Hunter and Dog's Most Wanted star looked normal. In the video, the journalist interviewing him refers to how he had just been standing and acting like a normally fit man, not someone suffering from heart troubles.

His "broken heart" comment refers to his grief after the death of his wife, Beth, who died in June at the age of 51 after a lengthy battle with cancer. Chapman has done several interviews since and worked to promote his new show on WGN. He's also dealt with stress-inducers like the burglary at his family's store in Colorado and internet scammers using his wife's name to try to take money from fans.

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