Seven people have died in recent years after receiving unapproved German-made artificial hearts at a Chinese hospital, state press reported Thursday.
The Shanghai Eastern Hospital conducted at least nine artificial heart transplants between 2001 and 2005, the Beijing News said, quoting city government officials.
Seven of those patients died and an eighth was left brain-dead, it said. The ninth was said to be alive but in poor health.
The hospital is being sued by the family of one of the patients, Zhou Yiqing, who died in 2005 at age 13 -- a year after receiving the artificial heart.
"The hospital used an artificial heart made by its German partner... which had not received approval from China's food and drug administration," Zhang Shengfu, attorney for Zhou's parents, told the China Daily newspaper.
His parents are accusing the hospital of using Zhou as a guinea pig to test the artificial hearts and are seeking 132,300 yuan (17,400 dollars) in compensation.
An attorney for the hospital, Jiang Cheng, told AFP that the hospital had done nothing illegal, saying that government approval of such organs was not required at the time.
He told AFP the parents filed the lawsuit only after the hospital refused their request to waive more than 400,000 yuan in medical fees.
Jiang also insisted that the boy was given an extra year of life by having the operation.
"The boy was dying... he could have passed away within one or two days... the family of the boy had been grateful as he lived for more than one year after the surgery."
The brain-dead patient, identified only by his surname Deng, had received an artificial heart produced by another German company in 2001, the Beijing News quoted his wife as saying.
It was similarly unregistered in China, the paper said.
The reports made no mention of any potential criminal case against the doctor involved or the hospital.
A hospital spokeswoman refused to comment on whether all of the hearts used in the nine operations under question had received government approval or not.
China's organ transplant system has long been seen as chaotic and unregulated. To address widespread problems, the government has over the past year brought in a series of rules to regulate the industry.
In May, China formally banned the trading of human organs.