The investigation into the death of David Cason, 55, at Guy's Hospital found "unacceptable" clerical and communication problems had occurred during his treatment. It highlighted "significant failings which need to be rectified" in the way cardiac patients are treated at the hospital.
Mr Cason, a taxi driver, of Welling, Kent, was admitted to Guy's in March 1998 as a "clinically urgent" case for a heart bypass operation. He was already seriously ill and waiting for a kidney transplant after suffering from heart and kidney problems for two years.
His operation was cancelled on 25 March and again on 27 March because of a lack of intensive care beds. Hospital staff told Mr Cason's son, Scott, that his condition was not deemed serious enough to be considered an emergency case. Mr Cason died of acute heart failure on 29 March, the day before he was due to have the surgery.
The Independent Review Panel, set up to investigate Scott Cason's complaint against the hospital, found that there was an "inexcusable" delay in Mr Cason being referred to a cardiac surgeon because secretarial staff shortages meant a letter about his condition was not sent.
The panel recommended that the hospital review its policy on cardiac monitoring after finding that Mr Cason was waiting in the renal unit for his operation, but was not attached to a heart monitor.
In a statement, Guy's and St Thomas' Hospital Trust said that since Mr Cason's death the number of cancelled heart operations had been reduced by 62 per cent.