Then they inflate the balloon, knocking the valve's flaps fully apart.
For example, when a valve isn't opening fully, surgeons insert a catheter with a tiny balloon into a vein in the body and push it through until it reaches the constricted or stenotic valve inside the heart. When either scenario is present, the heart must work harder to do its job. There are two main types of troublesome valves - valves that don't seal and allow some blood to move backward (known as regurgitation), and valves that don't open wide enough to let the right amount of blood move forward ( stenosis). Murmurs can, however, signify a serious problem. Many innocent murmurs disappear on their own by adulthood. Fortunately, most of these childhood murmurs are known as "innocent murmurs," meaning they're harmless and don't require medical attention. About half of all kids have hearts that thump to a different beat. This illustration shows what an open and closed tricuspid valve might look like. This is the second half of your heartbeat - "Dub!" Once the passing electrical current contracts the ventricles, the blood inside them is forced through the open semilunar valves, which then slam shut. Oxygen-rich blood in the left ventricle, meanwhile, departs through the aortic valve that connects the heart to the aorta, the body's major expressway for the delivery of freshly oxygenated blood. Oxygen-depleted blood in the right ventricle leaves the heart through the pulmonary valve that connects to the pulmonary artery leading to the lungs. These valves direct blood from either ventricle to its next destination. These valves leading out of the ventricles represent the heart's exit doors, and together they're known as the semilunar valves. Now, on either side of the heart, the second set of valves opens. This shutting of the atrioventricular valves creates the first sound of your heartbeat - "Lub!"īy this time, the heart's electrical signal has passed from the atria into the ventricles, so while the atria relax, the ventricles contract. Once both ventricles simultaneously fill with blood, the atrioventricular valves slam shut, preventing blood from moving back into the atria. On the right side, where oxygen-depleted blood is passing into the right ventricle, it's known as the tricuspid valve. On the left side, where oxygenated blood is coursing through, this gateway to the left ventricle is called the mitral valve. In the next section, we'll learn more about how these valves keep a mob from forming inside your heart. But no, when we get back from the concert, remove our earplugs and collapse in bed, all we faintly hear is the sound of those four turnstiles - the valves - moving two at time. With that much activity, it's amazing that the sound of your heart doesn't keep you up at night. Regardless of whether a red blood cell is holding a ticket for the lungs or a ticket for the arteries leading to the rest of the body, it will have to pass through two different chambers and two different valves as it's propelled out of the heart and on to its destination. This scenario, minus the expensive nosebleed seats and the $50 concert T-shirt, is similar to how the valves in your heart work. If anyone goes through one and tries to go back, no luck. As these would-be rockers cross through this second set, the turnstiles rotate in sync and make a different noise - dub.Īll night long, people in both lines simultaneously pass through these two sets of turnstiles - lub-dub, lub-dub, lub-dub. Now the two people in separate lines shuffle forward a few steps to the next turnstile to pass through security.
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