Holly Branson, 26, a doctor, was on board a Virgin Atlantic jetliner owned by her father during a recent flight from London's Gatwick Airport to the Caribbean island of Antigua when the incident happened, The Daily Telegraph reported Monday.
Company officials said Holly Branson came forward to offer to help when 47-year-old Paul Norbury, whose nationality and hometown were not reported, fell ill with a heart attack. Branson checked Norbury's pulse and blood pressure, administered oxygen and spoke to medical experts on the ground.
She advised the pilots of Virgin Flight VS33 to make an emergency landing at Shannon Airport in Ireland and Norbury was taken to Ennis General Hospital by ambulance after the plane landed, the newspaper said.
"I'm incredibly proud of Holly and pleased that her qualifications were able to save the life of one of our passengers," Richard Branson said in a released statement.