HCA Holdings says the Justice Department wants information about heart procedures performed at some of its locations.
The nation's biggest hospital operator also says in an unusual posting on its website that The New York Times may soon run news stories on patient care at its hospitals. The Times declined to comment when contacted by The Associated Press.
Shares of the Nashville, Tenn., company fell more than 6 percent in afternoon trading.
HCA says the U.S. Attorney's Office in Miami is asking for information about reviews that assess the medical necessity of some interventional cardiology services. It says the Justice Department has contacted HCA as part of a national review of whether charges for implantable cardio-defibrillators met government criteria.
On its website, HCA says the Times may run articles that appear "to be making broad points concerning patient care provided at our company's affiliated hospitals."