"Aortic stenosis. When we talk about aortic stenosis, we're really talking about the valve that's in the aorta that lets the blood out of the left ventricle so that blood could get to the rest of the body. There is a condition called calcific aortic stenosis. And what that means is as we age, calcium deposits on the valve leaflets and leads to progressive hardening and restriction of the valve leaflets, such that that valve doesn't open very well. This leads to symptoms, including heart failure, angina and syncope, meaning passing out. And obviously when patients are symptomatic with this, it's not just that the symptoms affect their quality of life, but more importantly, as you start to develop symptoms, your survival is shortened. So once you develop heart failure, your survival with aortic stenosis is less than two years. So obviously when we identify a symptomatic patient with aortic stenosis, we'd want to replace that valve. And typically, traditionally, we've been doing that with surgery, meaning open the chest through a sternotomy and replace that valve. And that has worked very well. And it's a viable option even today. But alternatively, over the last decade, we've had improved technology. We're an interventional cardiologists, such as myself could go in through the arteries, typically the femoral arteries and the groids and deliver this valve that's collapsed and cramped onto a balloon and delivered through a catheter into the aortic position. And then the balloon is inflated. The valve sits in place and the hemodynamics take over. So such that immediately the patient has a working valve. And most of our patients today are leaving the hospital before two days, some have left the hospital within one day and their quality of life is obviously markedly affected by this therapy. So this is the heart. And what you see is that the muscle is removed such that you can see inside. The septum, which is the wall between the right and left heart would be sitting right about here. This muscle here, the left ventricle is here, and this is the aortic valve, the outflow from the left ventricle to the body that allows the blood to go out. And what you see here already in place is a transcatheter aortic valve, a stented valve in position. And what this valve looks like, you know, outside the body is like such where you see the valve open and these leaflets that are made out of tissue, that's actually cow tissue, specially treated and mounted on the stent, opens and closes like a normal valve would as the heart pumps the blood out to the body. So you see here is one of these valves mounted in place in the aortic position. What this valve looks like is such where there is tissue from a cow that's treated specifically and mounted on the stent. And that once this valve is in position, the old valve, which is now crushed around, that is holding it in place. And the human dynamics of the heart pumping, opens and closes the valve leaflets."