Medtronic PLC has received government approval to sell an improved implantable heart monitor that wirelessly reads and transmits patient data to detect problems and help pinpoint causes of unexplained fainting and strokes.

The Minnesota-run medical device company announced Monday that the Food and Drug Administration has granted clearance to sell the Reveal Linq cardiac monitor with new computer programming called TruRhythm Detection. The new programming makes the capsule-sized implantable monitor more accurate than prior versions of Medtronic's Reveal Linq device.

With the Linq already generating more than $500 million in annual revenue, Medtronic has told investors that the device is an example of "transformative innovation" — a label reserved for Medtronic devices with the highest growth potential, including the Micra leadless pacemaker and the CoreValve aortic heart valve. All three heart devices are implanted with minimally invasive procedures, not surgery.

In June 2015 Medtronic officials said the Linq device could contribute as much as $1 billion a year to the company's top line within five years, although Medtronic's hasn't updated that projection in an earnings call since then.

Doctors implant the Linq when patients come in with unexplained strokes, fainting episodes known as syncope, or suspected atrial fibrillation. The Linq is inserted via the skin in a 1-millimeter incision in the upper chest.

The data it generates are sent wirelessly to the patient's bedside monitor, which then sends the information to the doctor.

The Linq scans a heartbeat for problems. A heart that quivers in atrial fibrillation may be allowing blood clots to form that can travel to the brain and cause strokes. A heart that's not beating quickly or regularly enough might be cutting down on blood flow in a way that can cause fainting.

A key advantage of the Linq device is its three-year battery.

Dr. James Allred, an electrophysiologist in Greensboro, N.C. and a paid speaker for Medtronic, said older cardiac monitors gathered data for 30 days.

But doctors at the center where he works found 30 days was not enough time to detect a problem like atrial fibrillation.

"What we have found when we follow patients for 18 months is that 27 percent of them have atrial fibrillation detected on their monitors," Allred said in an interview. "The interesting thing is that from the time of implant to first detected episode of AFib is, on average, 50 days."

That increased rate of detection is also good for Medtronic. About 9 percent of patients who get a Reveal Linq device will end up getting a pacemaker within one year; within three years, 20 percent of Linq recipients get a pacemaker, which is known as "pull-through" in sales vernacular.

Medtronic pacemaker sales have benefited as a result.

Heart-device companies Biotronik and Abbott Laboratories' St. Jude Medical unit make competing implantable cardiac monitors to the Linq.

Although Medtronic declined to release pricing information for the Linq, an August 2015 blog post by the hospital consulting firm MD Buyline said the device carried a price tag for hospitals of up to $5,295.

Meanwhile, hospitals are typically paid about $7,400 for the implant procedure.

Allred said only a couple of the hundreds of Linq patients in his office have had problems getting insurance to cover it. And he said the device is tolerated well by patients.

"I've had very little complaints with discomfort, no real issues with infection. I find the patients are happy with the results," he said.

Joe Carlson • 612-673-4779