Americans rely on the Food and Drug Administration to make sure that medical devices are safe.

Now reporting by KFF Health News raises questions about how the agency has dealt with some products, including one that treats a heart

condition.

Ali Rogin has more.

The device is called Mitroclip and its goal is to fix leaky heart valves, often in patients too sick for surgery.

It's implanted by snaking a small clip

into the heart through a major vein.

Now a new investigation by KFF Health News

looks into question surrounding the device's development, promotion, and

use since it was approved by the FDA back in 2013.

David Hilsenrath is the senior Washington correspondent for KFF and was the lead author of this story.

David, thank you so much for being here.

What type of patient was this device developed for and why was it such a game changer?

Mitr clip is used to treat patients with a condition called mitral regurgitation or

MR in which blood flows backward through the heart's mitral valve.

MR can lead to heart failure and death.

I've seen estimates, Ali, that millions of people in the United States experience MR,

including 10% of people over 75.

The Mitroclip system includes a tiny clip that is implanted in the Mitral Valve

to fasten the two flaps of the mitral valve together and enable them to achieve

a tighter seal.

And what was then the reality of what you found about how what this product says it does

...