Doctors were baffled when an apparently healthy man died two days after a successful heart operation, an inquest heard.

Peter Stanford was said to have been enjoying an "amazing" recovery from the triple heart bypass and surgeons believed he had every hope of a long and successful life.

Mr Stanford, 66, of King Alfred Close, Steyning, was sitting up in bed doing a newspaper crossword and chatting when he suddenly collapsed.

Within minutes he was unconscious and an hour later he was dead, a nurse told Brighton coroner Veronica Hamilton-Deeley.

Senior staff nurse Lise Quesnell told the inquest there had been no problems with Mr Stanford's heart rate, blood pressure or breathing immediately before he collapsed.

Wilfred Pugsley, consultant cardiothoracic surgeon who carried out the operation at the Royal Sussex Country Hospital, Brighton, said he had never seen a case like it.

Another cardiothoracic surgeon, Ramaswami Ramanan, said it was not uncommon for patients to experience problems in the hours following an operation but it was "very rare" for such problems to emerge two days later.

Mr Ramanan said: "As surgeons we all have an ego that we can do it, we can fix it. But unfortunately here, despite our best efforts, we couldn't."

Mr Stanford's partner, Margaret Hodge, told the inquest the former police officer had seemed chatty, comfortable and happy to be alive when she left him, about an hour before he collapsed.

A post-mortem examination showed Mr Stanford had a small perforation in a vein near the site of the bypass. There was no clear evidence to show how it happened.

The coroner, who recorded a verdict of death by misadventure, said: "I am completely satisfied the operation was properly and competently carried out."