After the ambulance arrived she was in the vehicle for 20 hours outside hospital.
A 90-year-old woman waited 40 hours for an ambulance to arrive after a serious fall.
Stephen Syms said his mother, from Cornwall, fell on Sunday evening and was made a priority by NHS 111 at 11:00 BST on Monday.
An ambulance arrived on Tuesday afternoon and she was in the vehicle for 20 hours at the Royal Cornwall Hospital before being admitted.
South Western Ambulance Service said it was “sorry and upset”.
Mr Syms, from St Stephen, told BBC Radio Cornwall: “We are literally heartbroken to see a 90-year-old woman in such distress, waiting and not knowing if she had broken anything.
“The system is totally broken.”
He said it took nine minutes before his 999 call was answered.
“If that was a cardiac arrest, nine minutes is much too long, it’s the end of somebody’s life,” he said.
Mr Syms said paramedics were “absolutely incredible people”.
He added: “The system is not deteriorating, it’s totally broken and needs to be urgently reviewed.”
A spokesperson for the South Western Ambulance Service NHS Foundation Trust said: “We are sorry and upset that we were unable to provide Ms Syms with the timely response and care that she needed.
“Our ambulance clinicians strive every day to give their best to patients.
“Health and social care services are under enormous pressure.
“We are working with our partners in the NHS and social care in Cornwall, to do all we can to improve the service that patients receive.”
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