A senior doctor has been jailed for two-and-a-half-years and criticised for being "far too laid back" as a patient died at a private hospital.
Surgeon David Sellu, 66, was found guilty of gross negligence manslaughter over the death of father-of-six James Hughes.
Mr Hughes, also 66, died at the Clementine Churchill Hospital in Harrow, north west London, on February 14, 2010 after falling unexpectedly ill following knee surgery.
His wife, Ann, described the suffering experienced by their family in a victim impact statement put before the court.
"For three years we have struggled to discover and then accept the truth of what happened to Jim," she wrote.
"The world does not stand still but for us we have been subjected to a tortuous purgatory that can only be brought to an end by truth and justice.
"Our trust in normal processes, authorities and structures of society was shattered by the inexplicable, callous and deceitful actions of the medical profession entrusted with the most basic responsibility to protect human life."
The judge, Mr Justice Nicol, asked prosecutor Bobbie Cheema QC to read out extracts of the full statement at the Old Bailey.
Mr Hughes, a retired builder, had a planned left knee replacement on February 5, 2010.
The operation went well but while recovering from surgery he developed abdominal pain and was transferred to the care of Sellu, who was a doctor for four decades.
He suspected that there had been a rupture in Mr Hughes' bowel - a potentially life- threatening condition that requires surgery - but the surgeon ignored the urgency that the case demanded and the patient later died.
Frances Hughes, one of the victim's daughters, said outside court: "For three years we have all struggled to discover and then accept what happened to dad.
"As a family we are grateful that a light has now been shone on the truth. We hope now it is less likely another person will suffer like he did."
In his sentencing remarks, Mr Justice Nicol said Sellu "was simply far too laid back for someone with a suspected perforated bowel".
He went on: "This was not a single isolated act of negligence. There were several. Nor were they committed in the pressured circumstances of an acute NHS hospital where the stress of dealing with very many patients in an emergency condition can be particularly challenging."
The judge told Sellu that "several failures" in his care meant his "culpability is high" and "that negligence contributed significantly to the death of Mr Hughes".
Sellu, a general surgeon with a specialism in colorectal surgery, ordered a CT scan for the next day rather than operate immediately on the suspected rupture to Mr Hughes' bowel.
The scan confirmed the medic's suspicions but he failed to carry out the surgery immediately and instead carried on with his own clinic.
After being in pain for around 40 hours, Mr Hughes was sent to the operating theatre at 9pm on February 12.
But by this point the situation had deteriorated so badly that intensive care specialists had to work to stabilise Mr Hughes before Sellu could operate on his bowel.
Four hours later, at 1am, Sellu was eventually able to operate.
During the trial Ms Cheema said: "He did what he could at that late stage to repair the damage."
After surgery Mr Hughes was transferred to the intensive care unit but he died there the following day.
"That death was avoidable," Ms Cheema said.
"Had (Sellu) operated the night before or even earlier on February 12, Mr Hughes would have had a very good chance of survival.
"Mr Sellu's care of this patient on this occasion fell very far below an acceptable standard.
"There was a series of missed opportunities and serious errors in judgment in the care of this patient and they combined to cause Mr Hughes' death.
"The standard of care was exceptionally bad."
Sellu, who gave no reaction as he was jailed, was told he will serve half his sentence in custody.