Among other things, the records indicate that company executives debated whether to warn doctors that some heart defibrillators could short-circuit.

Yesterday, Guidant reported that its fourth-quarter earnings fell sharply from the year-earlier period, a result of heart defibrillator recalls and lost sales.

Business Technology A $1 billion market by 1996 is expected for heart defibrillators, which deliver electric shocks to correct irregular heartbeats.

But high-tech remains in favor, despite recent studies raising doubts about the value to many patients of widely used medical devices like heart defibrillators.

An episode that drew particular attention to the agency was its handling of heart defibrillators made by the Guidant Corporation.

They ranged from the size of type required on drug packages to standards for lifesaving heart defibrillators.

The action stands to heat up the $650 million worldwide market for heart defibrillators, which has been dominated by Medtronic Inc. of Minneapolis.

At the time, Guidant executives were faced with the choice of recalling potentially defective heart defibrillators or allowing doctors to implant them.

And in hospitals, thousands of heart defibrillators made by Hewlett-Packard stopped displaying the correct date and time.

The system could kill people if it fails, such as aircraft controls, chemical factory controls, train signals, and heart defibrillators.