Welcome to Dr. Warrick's podcast channel. Warrick is a practicing cardiologist and author with a passion for improving care by helping patients understand their heart health through education. Warrick believes educated patients get the best health care. Discover and understand the latest approaches and technology in heart care and how this might apply to you or someone you love. Hi, my name is Dr. Warrick Bishop and I'd like to welcome you to my podcast station and to the Healthy Heart Network. Today I'm going to be talking about some of the problems that occur with the valves of your heart. When we start to think about heart valves, we need to think about, well, how many heart valves are there? Well, there are... four heart valves there are four chambers to the heart there are two chambers that are the right heart and there are two chambers that constitute the left heart there's a top chamber that's the atrium there's a bottom chamber that's the ventricle so blood comes in from the veins into the right side of the heart the first chamber it's the atrium the atrium gives it a squeeze and the first valve that the blood encounters is the tricuspid valve. All the valves in the heart are one way and they stop the blood coming from whence it just came as the heart squeezes. So blood passes through the tricuspid valve and fills the ventricle. When the ventricle squeezes the tricuspid valve closes and blood is forced forwards if you like into the lungs through the pulmonary valve. When the ventricle stops squeezing And forcing that blood through, then the pulmonary valve closes, stopping reflux of that blood back into the right ventricle. As the blood moves through the lungs, through the right ventricle, squeezing it, but also through the action of respiration and through the action of the left heart relaxing and almost sucking blood into it, then blood flows into the left atrium. From the left atrium, it goes through the mitral valve into the left ventricle. The left ventricle squeezes. The mitral valve closes and blood is squeezed out into the aorta. The aortic valve closes when the ventricle has completed that task. Sounds a bit complicated, doesn't it? But it seems to work. And as long as everything's going in one direction, then things work pretty well. So Kathleen's question was a bit about what goes wrong. Well, the valves that have the most wear and tear are the valves on the left side of the heart. And that's because the left side of the heart is the higher pressure system. So there's higher pressures operating, greater wear and tear. The pressures into the lungs are fairly low in comparison, 20, 30 millimetres of mercury. The pressures in the right heart... are up around 100 millimetres of mercury and more. So it's not surprising to think that the valves on the left side of the heart tend to be the ones that are most affected and the ones where we see most problems. Well, let's start with the aortic valve. And when we think about the aortic valve, as when we think about every other valve, it can be too sticky, so troubles with blood getting through it. Or it can be leaky. So there's only a couple of things that can go wrong with a valve. Too sticky. We call that stenosed. Another word would be narrowed. Or leaky. We call that regurgitant or incompetent. It doesn't matter what you call it. Either way, if it's leaking back, that's a problem if it's too much. So the aortic valve, when we think about narrowed valves, We can see this as a situation that can arise with people who have congenital abnormality of the shape of their valve. So most of us have three leaflets to our aortic valve, like a three-leaf clover. But sometimes people have only two leaflets. The three-leaf clover hasn't formed properly. And if you get a valve that only has two leaflets, then the wear and tear on that can be increased hemodynamics that it was designed to have. A two-cusp valve, a valve with only two leaflets, is called a bicuspid or bileaflet valve. Our normal aortic valve is tri-leaflet or tricuspid. So bicuspid aortic valves can be a cause of premature wear and tear on the aortic valve such that it gets all narrowed, tightens up, and needs to be replaced. One of the other things that can affect the aortic valve is rheumatic fever. So an infection during childhood where subsequently the valve can scar and over time lead to greater wear and tear causing a problem. Well, the only way to know about that is if you were sick as a child then a murmur may well be picked up down the line and that would give you the opportunity for that to be tracked by your doctor. Leaking aortic valves can be congenital. So a valve that is bicuspid and doesn't close properly could give rise to a leaky valve. A valve that's been affected by an infection, for example. Imagine a bug gets caught on one of the leaflets of the aortic valve. If that occurred, then that bug could cause local damage to the valve so that when the infection is finally cured, The valve may have areas that are just not working properly. Sometimes congenital conditions of abnormal tissue formation can give rise to valves that leak and even aortas that dilate. These are complicated issues, so I'm not going to dwell on them too much. The mitral valve is also commonly affected. rheumatic fever is the most common cause of the mitral valve being tight or stenosed where an inflammation and ongoing grumbling scarring process of the mitral valve leads to it becoming narrowed and that can be a problem because it stops blood getting through. The mitral valve can also leak and we see that in the situation where particularly if someone is born with a floppy or redundant leaflet which increases the wear and tear on the mitral valve so people can be born with valves that are just a bit floppier than usual and we would call this floppy mitral valve leaflet syndrome which is a bit of a mouthful but it basically means that the leaflets congenitally are prone to being a bit more floppy and therefore suffer a bit more wear and tear those leaflets then can rupture and give rise to leaking of that valve. The other valves are less commonly affected. The tricuspid valve on the right-hand side of the heart, we can see that leak, particularly if the pressures in the lungs are increased. If you think about it, the lungs are where the tricuspid valve, sorry, the right heart is squeezing blood into the lungs. As the right heart is squeezing blood into the lungs, then the back pressure in the right ventricle is what the tricuspid valve is subject to. So increasing pressures in the right side of the heart are all transmitted back through the tricuspid valve. A leaky tricuspid valve can come about when the pressures are really high in the lungs, but also if the right heart is failing a bit and the ring, the fibrous ring that holds the leaflet together is dilated and stretched a little bit. Pretty uncommon to see stenosis of the tricuspid valve, but it can occur in rare conditions. Pulmonary valve, generally not much of a problem. It is a low-pressure system. We don't see too much in the way of regurgitation in that particular valve, but we can see problems with congenital narrowing. Our intervention in that situation is really based on all sorts of parameters to do with how the right heart's functioning, to do with the pressures over the valve. So I've given you a very quick run through on valves. They can be problematic because we're born with a predisposition that can increase wear and tear, leading to the valve either being narrowed or leaking. The valves can be affected by infection. Rheumatic fever is probably the one that we've heard of the most. Bacterial endocarditis, where a bug settles on the valve, can also cause damage. So what's the consequence of valves going wrong? Well, it really depends on how bad the valve problem is. If you think about the valves being central to the pump system working, to the circulation working, to blood flowing in a continuous way around the body, then if a valve is either too tight and not letting enough blood through, it can cause a problem. If it's leaky and too much blood is going backwards, then that will cause a problem as well. Generally, shortness of breath are the sort of features that people might get if they had a problem with their valve. It generally doesn't cause any sort of pains. mainly shortness of breath and a diminished exercise capacity. It's a really useful thing to get your doctor to have a listen to your heart, just to make sure there aren't any noises there, because generally, if there is a significant valve problem, it will give rise to a murmur that is audible and your doctor should be able to hear. In general terms, it's not a bad idea. If there is a noise in your heart, a murmur audible to get an ultrasound of the heart, and get some clarity around exactly what's going on. There's lots more detail about individual valves and how we deal with those and what sort of investigations we do to figure out what the best solution is for the individual patient. And I really don't have the scope to go through all that right now. But I hope I've given you a little bit of an overview. I hope you've got a better understanding of the aortic valve, the mitral valve, the tricuspid valve, and the pulmonary valve. I'm going to wish you all the very best. Until next time, if you have any queries or questions, just drop us a note, let us know. If you've got any other ideas for any future presentations, please let us know. For now, all the best, and I hope you enjoyed that short presentation on valves. You have been listening to another podcast from Dr. Warrick. Visit his website at drWarrickbishop.com for the latest news on heart disease. If you love this podcast, feel free to leave us a review.
