A hospital trust lost track of patients referred to them for treatment and failed to meet government targets on waiting lists, it has been revealed today.

North West London Hospitals NHS Trust, which manages Central Middlesex, Northwick Park and St Mark’s hospitals, announced the blunder hours after the Care Quality Commission (CQC) named them as presenting high risks for patients.

According to a report by the independent health regulator, the trust has been placed in risk band two.

The CQC ranked trusts in bands, with band one representing those where there was the highest risk and band six the lowest.

An investigation has been launched by the trust into the gaffe which affected 2,700 patients in total with 1,700 of them waiting more than 18 weeks for definitive treatment after being referred by a GP.

The blunder came to light in April after a glitch was found in the system used to record patient waiting times and the following month it came under review by an external NHS department.

Hospital bosses have since sent out apologetic letters to the patients waiting to be treated assuring them they will be offered an appointment “as soon as possible”.

They have also set up a helpline for affected patients and written to their GPs.

David McVittie, the trust’s chief executive, said: “I am sorry for the distress that may have been caused to patients and their families who may have lost confidence in us.

“Our information systems weren’t consistent across each department, they weren’t good enough. We were not doing sufficient checks.”

According to Dr Rory Shaw, the trust’s medical director, there had been no increase in deaths of patients on waiting lists compared to the last three years.

He added: “We have also fully overhauled our systems and are confident we will not have a repeat of these unnecessary delays for patients in the future.”

The trust has vowed to offer appointments to referred patients within six to eight weeks and definitive treatment in the government’s time frame.

It is increasing operating theatre sessions and extending outpatient clinics to cover evenings and weekends to cope with the backlog.