St. Louis Medical Examiner Michael Graham said he watched that surveillance footage as part of his investigation. “There were prescription medications in her system that were all expected to be there in the amounts we would expect to see. There were no illicit substances found,” Graham said.
He determined Walker died from a condition known as nonischemic cardiomyopathy. “It’s a disease of the heart muscle,” Graham said. “It usually affects older people with high blood pressure, but she did not have high blood pressure.
“We don’t know why some people develop it. Hers was a fairly mild form. It essentially short-circuited the electrical system in her heart, causing arrhythmia and she dropped over. We don’t normally think about people dropping over dead, and it is fairly unusual, but it’s not a usual age for the presentation of this condition.”
He also said he did not believe any potential previous illicit substance use would have caused this condition.
“If there was, I would have called this alcoholic heart disease or cocaine heart disease,” he said. “But there was no evidence of that.”