A man accused of fatally stabbing his 82-year-old wife in Wantagh was charged with second-degree murder.

Police say officers responded to a welfare check Saturday at a home on Oakland Avenue at around 11:30 a.m. after the couple's adult son alerted authorities. They discovered the victim, identified as Mary Heaton, deceased on the floor with multiple stab wounds.

"When officers arrived at the scene, Mr. Anthony Heaton, who's 74 years old, met the officer at the door and announced he had stabbed his wife," said Nassau Homicide Squad Commanding Officer Stephen Fitzpatrick.

Anthony Heaton was arrested. Authorities say the couple had been married for 40 years and had no history of domestic violence.

Police say the victim had lingering health problems that triggered Anthony Heaton to plot her death and his suicide.

“Her health has been diminishing over the years, and the overwhelming stress of taking care of her and what comes with her declining health got to him. He couldn’t take it, and he planned to take her life and commit suicide. He stabbed her multiple times, strangled her, caused her death and did not kill himself,” Fitzpatrick said .

Anthony Heaton pleaded not guilty. He is due back in court on Tuesday. He was being held without bail as of Sunday night.