A Centennial man is facing charges of second-degree murder and assault after he allegedly shook his girlfriend so violently she sustained a fatal brain injury, according to an arrest affidavit.

Matthew Ivester, 37, is accused of second-degree murder, five counts of assault and harassment in the death of 36-year-old Stephanie Long.

Ivester called police just after midnight on Sept. 18 to report that his girlfriend, Long, might not be breathing, according to an Arapahoe County arrest affidavit.

The first officer who responded to the home in the 6700 block of South Ivy Way performed CPR on Long and she was transported to AdventHealth Littleton hospital.

Ivester told officers he and Long had been drinking and watching the Denver Broncos game when they started arguing and Long headbutted him, according to the affidavit.

Ivester changed parts of what he told law enforcement about the incident, including that he may have struck her that day but didn’t remember.

Investigators found video footage from inside the home that showed Ivester and Long arguing earlier in the day, which escalated into Ivester grabbing Long by the throat, violently shaking her and slapping her, according to the affidavit.

At one point, the video showed Long bleeding from the mouth and trying to call 911 through Google, after which Ivester took her phone away, according to the affidavit. Long also appeared to try to leave through the front door, but Ivester stopped her.

Hospital staff told police Long suffered from cardiac arrest and fell into a coma and would not survive her injuries. She had sustained a large brain bleed, brain swelling and herniation, according to the affidavit.

Long was declared brain dead on Sept. 20, according to the 18th Judicial District Attorney’s Office.

Ivester is set to appear in court on Nov. 6 for a preliminary hearing, according to court records.

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