Authorities revealed Friday that actor Gene Hackman died of heart disease and showed severe signs of Alzheimer’s disease a full week after his wife died of hantavirus in their home.

Authorities initially ruled out foul play after the bodies were discovered Feb 26. Immediate tests for carbon monoxide poisoning were negative.

Chief Medical Investigator Dr. Heather Jarrell said it was possible that Hackman was not aware his wife was deceased in their home.

“Mr. Hackman showed evidence of advanced Alzheimer’s disease,” Jarrell said. “He was in a very poor state of health. He had significant heart disease, and I think ultimately that’s what resulted in his death.”