Georgina Whelan had claimed she stabbed partner Dean Needham by accident after a drinking session when a pet dog nudged her as she made a sandwich at an address in Leeds.
She was cleared by a Leeds Crown Court jury of attempted murder, but convicted of wounding Mr Needham with intent to cause him grievous bodily harm. The Recorder of Leeds, Judge Peter Collier, jailed 40-year-old Whelan for five years.
The court heard the knife went in Mr Needham's chest at a 45-degree angle and passed between his ribs, cut his heart and went into his spleen causing heavy blood loss.

Chest

When Whelan dialled 999 for an ambulance saying she had stabbed him, Mr Needham could be heard in the background saying it wasn't true.
The operator gave Whelan advice on how to stop the bleeding and she started chest compressions.
Judge Collier told Whelan: "It may be that what you did prevented his loss of life. He was taken to hospital, operated on and lived to tell the tale."
Judge Collier added: "The jury found you stabbed him not with the intention of killing him, but with the intention of causing him serious injury...there is no real accounting for why what took place did take place, but clearly something happened between you."
Mr Needham gave evidence on Whelan's behalf and the court heard he wants to get back living with her as soon as possible.
The court heard Whelan, of Ripon House Bail Hostel, Leeds, is addicted to booze.