A Pennsylvania nurse connected to the deaths of 17 patients who were given fatal doses of insulin was sentenced Thursday to hundreds of years behind bars.

Heather Pressdee of Natrona Heights pleaded guilty in a Butler County courtroom to three counts of first-degree murder and 19 counts of criminal attempt to commit murder, Attorney General Michelle Henry's office said in a news release.

Presdee, 41, was a nurse at Quality Life Services in before her arrest in May 2023.

Pressdee's crimes began in 2020, with her administering "lethal and potentially lethal doses of insulin" to at least 22 patients at facilities Allegheny, Armstrong, Butler and Westmoreland counties, prosecutors said. Seventeen of the patients "died very soon" or "sometime later" after receiving the insulin doses, according to Henry's office.

'This plea and life sentence will not bring back the lives lost'

Pressdee will be incarcerated for three consecutive life sentences after pleading to the three counts of first-degree murder, plus an additional 380 to 760 years of consecutive jail time for the 19 counts of criminal attempt to commit murder, according to prosecutors.

“The defendant used her position of trust as a means to poison patients who depended on her for care,” Henry said in a statement. “This plea and life sentence will not bring back the lives lost, but it will ensure Heather Pressdee never has another opportunity to inflict further harm. I offer my sincere sympathy to all who have suffered at this defendant’s hands."

Relatives of Pressdee's victims spoke during the registered nurse's sentencing hearing and said they experienced "pain and anguish caused by learning their loved one’s death was not natural, but was caused by a criminal act," Henry's office said.

"She's pure evil," said Melinda Brown, the sister of victim Nicholas Cymbol, according to WTAE-TV of Pittsburgh. "There's no justice for this. We'll get justice when she meets her maker."

Elizabeth Simons Ozella, daughter of victim Irene Simons, told the station that unlike some other victim family members, she will never forgive Pressdee.

"We're angry and hurt that she disguised herself as a caring nurse," she said. "She took someone from this earth that she had no right to take, and she played God when she didn't have that right."

How did Heather Pressdee get caught?

Henry became aware of Pressdee's crimes when her office received a referral in late 2022 regarding a patient under the nurse's care, according to Henry's office. A "comprehensive investigation" ensued and revealed the "numerous deaths" caused by Pressdee's actions.

Pennsylvania state records show Pressdee's registered nurse license was issued on July 31, 2018, and was going to expire at the end of October 2023. The license was renewed in August 2021 and marked active on the Pennsylvania Department of State website in May 2023 before Pressdee's arrest.

Pressdee was also disciplined at 11 former nursing jobs in Western Pennsylvania for "abusive behavior toward patients or staff, and either resigned or was fired from each facility," according to the initial criminal complaint obtained by the Pittsburgh Tribune-Review.

Charges against Pressdee were filed in May and November 2023, prosecutors said. Presdee remained incarcerated in Butler County prison since being arrested in her home.

'A very emotional day'

The initial goal for Pressdee's attorneys, Phil DiLucente and James DePasquale, was to avoid the death penalty, which their client did on Thursday.

"This was very hard to accomplish with this many deaths and attempted murder charges that either resulted in death or impairment," DiLucente told USA TODAY.

Before Pressdee had legal counsel, DiLucente said his client "wanted to confess and wanted to show contrition" regarding her crimes.

"Today is a very emotional day," the attorney said. "There's a tremendous amount of sad stories that were given by the victims' family members ... and Mrs. Pressdee did shed a tear several times, as well as apologize at the very end in front of an open court."

While a lot of family members didn't forgive Pressdee for her crimes, some did, which DiLucente said he and DePasquale did not expect.

"That's a little bit different than typical cases we handle," the attorney said.

Heather Pressdee believed 'she was helping'

Pressdee at one time "truly believed" that "she was helping" her patients, DiLucente said.

Before becoming a nurse, Pressdee worked in a veterinary clinic and her job was to euthanize animals, according to the attorney.

Pressdee believed she was ending the suffering of a lot of people by doing what she did, but now "she knows that that's not the case and she apologized for her actions," DiLucente said.

Contributing: Natalie Neysa Alund/ USA TODAY