Heart Disease – Stents

Transcript

“If you had a heart attack 50 years ago, we watched you recover from it. And if you lived, then we dealt with the consequences in terms of the damage to the heart and the heart failure and all the things that ensued after. If you had a heart attack 30 years ago, we were capable of doing angiography and, you know, some angioplasty, but our techniques were pretty primitive. And there were a lot of complications. Over time, our technology has improved and now we have balloons and we have stents. And what do stents offer to patients who could have had a balloon angioplasty? When you balloon a plaque, you basically stretching a balloon, crushing that plaque against a wall. But if you crumple a piece of paper, you know, there’s recoil. And if you crumple up plaque, you know, there’s going to be recoil. So what would happen is within 12 hours, those patients would reactivate, reclog, and then you’d have to go back and do repeated interventions.

And the long-term benefit was limited. So then we developed stents. And what are stents? Stents are basically like a spring or a scaffold that you implant in the artery that keeps that recoil from recurring. And that reduced the risk over time. But the bare metal stent, the original stents that didn’t have any drug coating, had about up to 60%, but typically 30% return within a year with scar formation, what we call instant restenosis or re-narrowing of an artery after a stent had been implanted. And that process was mainly, typically our body coats a stent with a layer of cells to kind of keep that foreign material from being exposed to the cells as they flow through. But what would happen is in bare metal stents, that proliferative response, or that layer of cells that came back, created layers and layers and layers of cells and such that the artery lumen narrowed and was constricted and the patient had symptoms again. And then for that, which we developed technology such as radiation, repeat angioplasty and all kinds of, you know, novel therapies that didn’t work very well in a long-term.”