A cardiac surgeon who inserted a heart valve the wrong way round has told his patient's inquest that stitches snapped at a crucial time.
Great-grandmother Sheila Hynes, 72, died days after an operation at the Freeman Hospital in Newcastle to replace two heart valves, which were diseased.
Surgeon Asif Shah told the inquest at Newcastle Civic Centre he had told Mrs Hynes that statistics showed there was a 6% mortality rate associated with that particular operation.
He told the hearing that the mortality rate for his own patients, across a range of procedures, was less than 2%.
He had carried out more than 350 open heart operations since starting at the Freeman in January 2015, two months before the operation which led to Mrs Hynes' death.
She had complained of shortness of breath, and the operation to replace the aortic and mitral valves was aimed at relieving her symptoms and extending her life, the inquest heard.
The consultant cardiac surgeon said the operation had been brought forward because Mrs Hynes' grandson was getting married later that year and her sister was terminally ill.
He said: "The procedure was going OK until the very last moment when I was tying down the mechanical valve and the stitch cord snapped."
This rare event meant he needed to remove the aortic valve he had inserted, and he told the inquest he handed it to a scrub nurse, ready for him to re-fit it.
Mr Shah said the valve was then placed on its mounting the wrong way round - something he was unaware could happen.
He then inserted the valve the wrong way round and stitched up his patient.
When attempts were made to re-start Mrs Hynes's heart, it was found there was a tear in the ventricle, which he fixed.
And when a second attempt was made, an even bigger tear was found which again needed to be repaired, with the surgery team concerned about the amount of blood loss.
It was only later in the day-long surgery, after the surgeon had called for senior colleagues' help, that the possibility that the valve could have been inserted the wrong way round was considered, Mr Shah said.
He said a senior colleague said he looked tired, and told him: "You've had a long day, you just go and have a cup of tea, take a break and I can replace the valve."
Mrs Hynes's two daughters and her son were at the inquest. A framed photograph of their mother, who was from North Kenton, Newcastle, was placed on the desk of their legal representative, Tim Wilkinson.