The actor Gene Hackman died from heart disease at his home in New Mexico about a week after his wife, Betsy Arakawa, died from the effects of hantavirus, which causes a respiratory illness and is associated with rodent droppings, the authorities said on Friday.

Alzheimer’s disease was a contributing factor to Mr. Hackman’s death, Dr. Heather Jarrell, New Mexico’s chief medical examiner, said at a news conference announcing the causes of death.

Mr. Hackman, 95, was found on the floor of the mudroom in the couple’s home, near his cane, while Ms. Arakawa, 65, was found on a bathroom floor, beside a counter with pills scattered about. They were not discovered until nine days after Mr. Hackman’s pacemaker indicated that he had died.

One of the couple’s three dogs was found dead in a crate not far from Ms. Arakawa’s body.

This is a developing story. Check back for updates.