BISMARCK-Kristina Kratz is finally able to tell her 8-year-old daughter how her father died, but that information came as a shock.

Mike Lang, 47, was an inmate at the Burleigh-Morton County Detention Center when he had a seizure at the jail, went into a coma and died Sept. 13 after a week in the hospital and days of testing. His family said he also had pneumonia, low blood sugar, a cut on the back of his head, a broken nose, broken cheek bones and broken ribs.

On Monday, the state forensic medical examiner publicly released his report on Lang's cause of death: arteriosclerotic and dysgenetic coronary artery disease.

"I'm shocked because he was healthy when we were together," Kratz said. "He had no problems with his heart or anything that would cause concern."

Lang was a type 2 diabetic, she said, and had a history of seizures, but hadn't had one since 2009.

But it was heart disease that state forensic medical examiner Dr. William Massello III says killed Lang's ex-husband. Massello also listed cardiac hypertrophy as another significant condition.

Massello listed Lang's manner of death as "natural."

He performed the autopsy on Sept. 14. His report of death contained no other details and no information about Lang's injuries.

"Since the case is under investigation, all we can provide is the report of death," said state health department spokeswoman Nicole Peske. "(North Dakota Bureau of Criminal Investigation) investigates all inmate deaths."

BCI spokeswoman Liz Brocker cited BCI media rules referring questions to the agency requesting the investigation. Massello's report lists the Burleigh County coroner and Morton County Sheriff's Office as the investigating agencies.

Maj. Steve Hall, of the Burleigh-Morton County Detention Center, said he requested BCI's investigation and spoke with the lead investigator two weeks ago. He said he was told the agency is waiting on documentation from the medical examiner.

"Until they get that, it's considered still opened," he said.

BCI is investigating the period from Lang's time at the jail to his death at the hospital, said Hall, adding that Morton County, the arresting agency, released its hold on Lang at some point before he died.

"If he was healthy, he could have got up and walked out," Hall said.

As for his various medical conditions, Hall said Lang would have indicated that information during an intake screening's medical questionnaire at the jail.

Regarding his facial injuries, Hall said to his knowledge, Lang was not involved in a fight before he left the jail on Sept. 6.

"Nothing in my knowledge indicates that occurred," he said.

Hall previously said Lang had a medical situation while sitting on his bunk to eat breakfast before jail staff intervened. During CPR, EMTs broke his ribs, Kratz said. According to Hall, Lang was breathing on his own when he left the jail.

Hall said he requested BCI's report be sent to the jail's oversight board under the North Dakota Department of Corrections and Rehabilitation. He and Morton County also will receive a copy.

Morton County spokeswoman Maxine Herr did not immediately return an email inquiry.

For Kratz and her daughter, she said every day is different. Some are good, some bad.

"She's coping with it," Kratz said. "She still can't understand why this had to happen."

Lang had just re-entered his daughter's life before his arrest in August, Kratz said. Their daughter was able to see him in ICU before he died.

Lang's family held a memorial ceremony for him on Nov. 21, Kratz said, after his relatives took time to grieve privately. Lang's parents did not return phone calls for comments, but they previously said they wanted to see their son's autopsy report and know the circumstances of his death.

Kratz said she had not seen her ex-husband's report of death before an interview for this story.

"That's a real shock," she said after reading the one-page report. "But now that I know, now I can hopefully tell my daughter and help her heal and try to move on from this."