Ambulance drivers were left clueless because their sat nav had not been updated with the road network on the Olympic Park.
The pace of development in east London was another contributory factor, an investigation concluded.
A cyclist with chest pains at the VeloPark, in Stratford , later died of a heart attack in hospital. The crew took more than 19 minutes longer than the target response time because of the blindspot.
London Ambulance Service (LAS) medical director Dr Fenella Wrigley said the service was “very sorry for the delay” which occurred on August 18 last year.
She said: “We have looked into the circumstances around the delay and have taken steps to improve knowledge of the area to minimise future risk.
“All of our staff have been made aware of the changes to road networks in the area.
“In addition, our response mapping books and a number of our systems now detail the surrounding area.”
The problem was exacerbated by a “large increase in new property developments”.
A report into the incident concluded: “LAS sat navs are updated on a regular basis but may not keep up with the pace of development and are reliant on individual postcodes being registered in a timely fashion.
“Crews were not always aware that the satellite navigation on ambulances may not accurately route to addresses in E20.”
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