Video report from Andrew Fletcher
Amanda Jameson , 51, from Merseyside, had lost consciousness after going to bed one night with dangerously low blood sugar.
Willow the cat's actions proved to be crucial, biting the leg of her partner Ray Sherwood, 57, who had fallen asleep in front of the television at home in Prescot, and pacing around to wake him up.
Willow then led Ray upstairs where he found Amanda unresponsive and called for an ambulance.
Mr Sherwood said: "It was very out of character for her and made me get up to see what all the fuss was about.
"She was running between me and the stairs, looking back at me. I followed her up the stairs and she kept looking back at me to make sure I was coming.
"When I went into the bedroom, Willow leapt onto the bed, and I could see Amanda slumped over. She was unresponsive and I called an ambulance straight away. She was very unwell and rushed to hospital where, fortunately, they were able to treat her."
Ms Jameson said:"Willow is amazing, I just think she's incredible. Since I came home from hospital, she has become very protective of me.
"I've noticed how she puts her nose to my mouth a lot, I think she's checking I'm breathing."
Willow has been included in the Moggy Marvels category.
The awards are run by Cats Protection - the UK's largest feline welfare charity.
It honours cats in four categories:
The public will have until 30 June to vote for their favourite cat.
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