The medical device maker St. Jude Medical played down the failure of some batteries in its defibrillators, shipping them for years before recalling the devices last fall, according to a warning letter the Food and Drug Administration issued this week.

The company, acquired by Abbott Laboratories in January, also failed to tell its own management and a medical advisory board that the battery problems had led to the death of a patient, the agency found.

The F.D.A. said St. Jude Medical had not shown it was taking sufficient action to fix the problems that led to the slow recall and ordered the company to provide a new reporting plan within 15 days.

Faulty defibrillators and other implanted devices are particularly problematic because removing them requires surgery that can be more risky than keeping them in. When the company announced the recall in October, the F.D.A. recommended that doctors closely monitor their patients’ devices for problems. Saying the malfunction did not appear to be widespread, the agency warned that “patients could be at greater risk of complications from the surgical procedure required to replace the device.”