A doctor found not guilty in the death of a 12-year-old girl in 2002 due to a heart operation error will see the ruling stand, as prosecutors said Friday they will not appeal the acquittal handed down by a district court and upheld on appeal.

The Tokyo High Court on March 27 upheld the acquittal of 45-year-old Kazuki Sato, who was accused of negligence resulting in death for operating an artificial heart-lung machine inappropriately during heart surgery on Akika Hirayanagi at Tokyo Women's Medical University Hospital and causing her to develop a brain disorder and eventually die.

"We cannot find a reason to appeal," the Tokyo High Public Prosecutor's Office said in a statement Friday.

The high court said it is highly likely the girl died because other doctors wrongly inserted a tube into her body to drain blood from a vein and sent it to the heart-lung machine.

It also said there is "no causal link between the defendant's operation of the artificial heart-lung machine and the death," dismissing the prosecutors' appeal of the 2005 Tokyo District Court decision that cleared Sato.