Forensic experts came to a heartrending conclusion Friday about the manner of death for actor Gene Hackman: he died of heart disease with complications from Alzheimer's disease on an empty stomach a week after a rare, rodent-borne disease took the life of his wife at their home in Santa Fe.

The partially mummified remains of Hackman, 95, and Betsy Arakawa, 65, were discovered Feb. 26 when maintenance and security workers showed up at the home and alerted police.

Authorities unraveled the mysterious circumstances and revealed that Arakawa likely died Feb. 11 at home from hantavirus pulmonary syndrome, a rare but potentially fatal disease spread by infected rodent droppings.

Hackman, in the advanced stages of Alzheimer’s, apparently was unaware that his wife was dead.

“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,” chief medical investigator Dr. Heather Jarrell said. “It’s quite possible he was not aware she was deceased.”

Both deaths were ruled to be from natural causes.

Santa Fe County Sheriff Adan Mendoza said Arakawa’s last known outing was a round of errands and shopping Feb. 11. She visited a pharmacy, pet store and grocery before returning to the couple's gated neighborhood that evening.

Arakawa stopped answering emails that day. The couple’s cellphone communications have not yet been analyzed.

Hackman’s pacemaker last showed signs of activity a week later, indicating an abnormal heart rhythm Feb. 18, the day he likely died, Jarrell said.

Hackman was found in the home's entryway, and Arakawa was found in a bathroom. Their bodies were decomposing with some mummification, a consequence of body type and climate in Santa Fe’s especially dry air at an elevation of nearly 7,200 feet (2,200 meters).

The revelations about the manner of the couple’s deaths jolted Santa Fe, the state capital city known as a refuge for celebrities, artists and authors.

“All of us that knew him should have been checking on him,” said Stuart Ashman, co-owner of Artes de Cuba gallery, who cherished his encounters with Hackman at a local Pilates exercise studio. “I had no idea. ... It’s just really sad. And that she died a week before him. My God.”

Experts believe Hackman was severely impaired due to Alzheimer’s disease and unable to deal with his wife’s death in the last week of his life — or seek help after she died.

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“Their (the authorities’) explanation, I thought, was quite clear and plausible, said Dr. Victor Weedn, a forensic pathologist in Virginia. "I believe they really discovered what truly happened in this case.”

Most older Americans with Alzheimer's diesease and related dementias live at home, and many receive care from family or friends.

Hantavirus typically is reported in spring and summer, often due to exposures that occur when people are near mouse droppings in homes, sheds or poorly ventilated areas. This is the first confirmed case of hantavirus in New Mexico this year.

While hantavirus is found throughout the world, most cases in the U.S. have been found in western states. The virus can cause a severe and sometimes deadly lung infection.

Jarrell said it was not known how quickly Arakawa died.

One of the couple’s three dogs, a kelpie mix named Zinna, also was found dead in a crate in a bathroom closet near Arakawa, while two other dogs survived.

Dogs do not get sick from hantavirus, said Erin Phipps, a veterinarian with the New Mexico Health Department. A necropsy will be done on the dog.

The sheriff considers this an open investigation until they receive results of the dog’s necropsy and finish checking into data from personal cellphones retrieved from the home.

Hackman, a Hollywood icon, won two Oscars during a storied career in films including “The French Connection,” “Hoosiers” and “Superman” from the 1960s until his retirement in the early 2000s.

Arakawa, born in Hawaii, studied as a concert pianist, attended the University of Southern California and met Hackman in the mid-1980s while working at a California gym.

Hackman dedicated much of his time in retirement to painting and writing novels far from Hollywood’s social circuit. He served for several years on the board of trustees at the Georgia O’Keeffe Museum in Santa Fe, and he and Arakawa were investors in local businesses.