Audrey, a lifelong CTC member who was 75, died two days after McCourt clipped the back wheel of her bike in Edinburgh in August 2011.
McCourt, who was 49 when sentenced in April, was banned from driving for five years and ordered to carry out 300 hours of community service by Sheriff James Scott.
At the end of his trial at Edinburgh Sheriff Court, it emerged that he was jailed for two years after being convicted in 1986 of causing another cyclist's death by reckless driving.
George Dalgity, 22, was killed as he cycled along Edinburgh's Regent Road on October 18 1985.
CTC, other cycling groups and Mrs Fyfe's family criticised Sheriff Scott's sentencing on grounds that it was unduly lenient, and the Crown lodged an appeal after 6,000 people  supported a CTC campaign.
A hearing took place before three judges at the Court of Criminal Appeal in Edinburgh on 13 August.
The trial sheriff had erred in applying the sentencing guidelines, resulting in an unduly lenient sentence, Solicitor General Lesley Thomson said.
The court was also told that he had been wrong to reach the conclusion that the incident had been the result of "momentary inattention" on the part of McCourt.
McCourt had admitted that he had manoeuvred before looking, and his failure to carry out the most basic principle of driving had directly resulted in the accident, Ms Thomson said.
The sheriff was wrong to take into account the fact that Mrs Fyfe was not wearing a cycle helmet."
Solicitor General Lesley Thomson
Ms Thomson said that no evidence had been presented about the effectiveness of wearing a helmet and the sheriff had "entirely formed his own view" on the matter.
Ms Thomson also told the court that there was "extremely controversial and disputed" scientific and medical research in the area and it was not clear cut; and that Mrs Fyfe was not at all to blame and it was wrong to suggest that the lack of a helmet had contributed to her death or was a mitigating factor for McCourt.
Insufficient weight had also been placed on McCourt's previous conviction for killing another cyclist.
"There is no indication how he considered the public was going to be protected from this particular driver who had killed twice," Ms Thomson said, adding that the starting point for sentencing should have been eight months'
"In the circumstances of this case it is an inevitability because of the culpability of the driving and because of the aggravating factors," she said.
The Crown also said McCourt should be disqualified from driving for life.
Defence advocate Herbert Kerrigan QC said the sheriff's approach to sentencing was correct and could not be criticised.
McCourt had been travelling at a slow speed and had clipped the back of Mrs Fyfe's wheel, after which she toppled over, Mr Kerrigan said.
"He [the sheriff] has applied some common sense," he told the judges.
"The fact of the matter is she [Mrs Fyfe] chose not to wear a safety helmet, which she was perfectly entitled to do. The sheriff has quite clearly weighed matters up with great care and concern."
I would like to see careless or reckless - whatever adjective you care to use - drivers who are responsible and found guilty of killing innocent road users, or seriously injuring innocent road users, to have a lifetime ban on driving.
"I feel that would focus the minds of careless drivers about what would happen because few people who drive want to lose their licence. That would send out the correct message.
Whether we will be successful, at least we tried to do something about it and convince the judges that the sentence was far too lenient considering the circumstances of his past history."
Lord Menzies, Lady Dorrian and Lord Glennie will give their decision in a written judgement. Lord Menzies said: "You have provided us with some food for thought. We will give our decision in writing as quickly as we can, but at a later stage."
Speaking after the hearing, Mrs Fyfe's widower Ian and daughter Linda Hamilton said they would like to see McCourt receive a lifetime ban as a result of the appeal.
Mr Fyfe said: "The sheriff put too much emphasis on the fact that my wife wasn't wearing a cycle helmet when it hasn't been proven that a cycle helmet would have prevented the death."
CTC Officer Kirsteen Torrance was on hand to support Audrey's family and read the following statement for the press on the steps of the High Court "On behalf of the family of Audrey Fyfe we would like to thank the members of the public, cycling community and CTC for their support today and for getting us to the appeal stage."
She continued, "We sincerely hope that the court will find this sentence unduly lenient and hope that this will result in imposing a lifetime ban. We call for the judiciary to put more emphasis on life time bans when drivers are found guilty of causing death of innocent road users."
The outcome of the hearing will be announced on the 25th September.