A catastrophic failure of surgical leadership was blamed for the collapse of the heart and lung transplant programme at a leading NHS teaching hospital where a high proportion of patients died.

Of 14 patients who had heart or lung transplants at St George's Hospital in Tooting, south London, between December 1999 and September 2000, 10 died. During April last yearthe unit lost three patients in four days.

An investigation by the Commission for Health Improvement, the Government's NHS watchdog, ordered by the Secretary of State for Health, Alan Milburn,concluded that the high number of deaths was not due to an "unlucky run".

It said national rates showed 80 per cent of patients survived at least one year after a transplant, suggesting that up to seven of the patients who died might have lived had they been operated on elsewhere.

Peter Homa, chief executive of the commission, said: "The wrong patients were given the wrong operations by a team whose leadership had broken down and who failed to follow their own rules about which patients should receive heart transplants.

"No one doctor is responsible for this but many people in many roles share an accountability for what happened."

The co-directors of the heart and lung transplant programme at St George's, one of seven transplant centres in England, were Andrew Murday, consultant cardiothoracic surgeon, and Brendan Madden, consultant physician.

Mr Murday was appointed this year to rebuild Scotland's transplant service based at Gartnavel Hospital, Glasgow.

The report criticises the "ad hoc and ineffective management of changes in surgical leadership" at St George's. It says that although Mr Murday had in effect withdrawn from his role as co-director to concentrate on post-graduate education in November 1999, no formal arrangements were made for alternative surgical leadership until March 2000. As a result, patients were often not assessed by a surgeon before being selected for transplant.

The report paints a picture of a dilapidated and dirty unit where morale was low. Staff reported seeing cockroaches and rats on the unit and "animal faeces" in the corridors. Rat traps were placed in the operating theatres, lavatories leaked and buckets were needed to catch drips when it rained.

A national review of transplant units by the Department of Health, under way at the time, was expected to result in the closure of St George's and "created an atmosphere of uncertainty", the report says.

The CHI found that patients at St George's were wrongly assessed as to their suitability for transplant or the type of transplant they should receive. Some had kidney failure but were not given heart and kidney transplants at the same time – the normal practice in other units. When they died their transplanted hearts, which are in short supply, were in effect wasted.

The report shows that from 1995 St George's had a higher mortality rate than the other six English transplant centres. One unit – at the Royal Hallamshire Hospital, Sheffield – "consistently achieved higher survival rates than other units" from 1995 to 2000.

The transplant team was commended for investigating the high death rate at an early stage but criticised for not sharing concerns with senior management. Mr Homa said: "The aspect that concerned us was the lack of knowledge by the chief executive at an early stage. It highlights the danger of semi-autonomous clinical fiefdoms in the NHS."

The report says the excess deaths at St George's were due to the breakdown of the leadership of the unit, the lack of a round-the-clock transplant co-ordinating team, the poor state of the unit, inadequate infection control and the small number of examinations carried out to determine why patients were dying.

The transplant programme at St George's has been suspended since September last year and is not expected to resume. A Health Department consultation paper to be published this month is expected to recommend the number of units in England be reduced from seven to four.

Ian Hamilton, chief executive of St George's NHS Trust, said he would be drawing up a plan to address the commission's recommendations. He said: "Patients build very close relationships with members of the clinical team, who deeply felt the loss of each patient."