U.S. health authorities have failed to act on repeated Japanese requests to report on defects in U.S.-made heart tissue patches that have caused problems in at least 68 patients in Japan, Health Ministry officials said Tuesday.

The officials said they asked the U.S. Food and Drug Administration, which oversees the maker, Shelhigh Inc., in both February and June to provide information and investigate the cause of the defect in Shelhigh's "no-react patches."

The officials' comments were contained in a document dated Tuesday in which they responded to questions raised by Mitsuru Sakurai, a member of the Democratic Party of Japan, in a letter submitted during parliamentary recess.

In July, the FDA demanded that the then Health and Welfare Ministry submit a statement pledging to respect the secrecy of information involving the U.S. manufacturer.

In reply to the demand, the ministry submitted the statement in August, but they have yet to receive information on the products from U.S. authorities.

As of the end of last year, at least 68 people had suffered problems since 1999 with the patches, the officials said.

Sakurai also asked in the letter when the ministry had first learned of the problem.

A Tokyo trading company that imported the products insists it reported the problems to the government on Aug. 9, 1999, while the ministry says the report was received Oct. 25 of the same year.

In Tuesday's document, ministry officials reiterated that they learned of the problem on Oct. 25, 1999.

Their statement added, "It will be no use arguing since we are determining the date based on our official documents."