Kirsty, 16, who is a pupil at Newall Green High School in Wythenshawe, Manchester, was born with her heart back-to-front.
This caused her internal organs to be misplaced and she needs a constant supply of oxygen to keep her alive. Her condition is so rare that she's only the second person in the world to be diagnosed with it - and it can't be cured with an operation.
On results day, Kirsty went out for a celebration lunch after spending the morning in hospital.
When asked about her exams she said: "It was scary but it went OK."
Kirsty is still classed as terminally ill - but that hasn't stopped her living life to the full.
She's already led a campaign to raise £5million for Francis House Children's Hospice in Manchester and, in 2004, she won the Helen Rollaston Award for courage at the BBC Sports Personality of the Year Awards.
She also led the England team at Old Trafford in 2011, and met her hero David Beckham again a year later when she handed over the Golden Jubilee baton to the Queen at the opening ceremony for the Manchester Commonwealth Games.
She's also met David and Samantha Cameron, as well as Tony and Cherie Blair.
She still does charity work through The Kirsty Club, which aims to keep improving the Francis House Children's Hospice. The money she raises will be used to expand the hospice to support more than 900 families of children with short life expectancy.
Back in 2010 she told The People: "Its not been easy but this is who I am and it's helped me to do a lot of good for others. My secret is to be positive, not to let anything get me down."
Huge congratulations from everyone at Parentdish, Kirsty!
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