Hundreds of miles away, Kimberley Williams answered the phone in Jackson, Mississippi.
"He said his name really clear, Daniel, and then he just got quiet," Williams, 32, told The Clarion-Ledger.
Magennis, 65, told MLive he tried to speak, but couldn't. His wife was away, and he was at the house alone without any neighbors nearby, according to The Clarion-Ledger.
“I started to panic," he said. "I would try to say something, and I just couldn’t. I couldn't move. Within 20-30 seconds, I started to think maybe it was a stroke, but I wasn’t able to tell the representative that."
"He was talking to me but I could not understand him," Williams said. "Then, his words got slurred."
Williams said the way he sounded reminded her of when she, at age 14, saw her grandmother have a stroke. She stayed on the line with Magennis and contacted her supervisor, Jennifer Clark. After making some calls to police departments in the Grand Rapids area, Williams got in contact with the Grand Rapids Fire Department.
Officials were able to get Magennis and take him to the hospital, where he underwent an hourlong surgery to unclog a blocked artery, The Clarion-Ledger reported. Today reported Dr. Justin Singer, a neurosurgeon at Spectrum Health Butterworth Hospital, treated Magennis, who has since been released from the hospital and is recovering.
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"He has almost no discernible signs of having a stroke (now), and that's what we want to see," Singer told WZZM.
"Kim is absolutely a hero," Singer told Today. "You can envision working in a busy call center and knowing that people get interrupted during their phone calls. It would be so easy for her to dismiss it."
"Each day, our Customer Experience Associates in Jackson, Mississippi, and across the nation go above and beyond the call of duty to take care of our customers," Alex Horwitz, a vice president of public relations for Comcast, said in a statement to People. "In this case, Ms. Kimberly Williams took the extra steps to help save a customer's life. We are incredibly proud of her quick thinking and dedication."