The heart has four valves. They are the aortic, pulmonary, tricuspid, and mitral valves. The valves open and close to keep blood moving in the right direction through the heart. Blood moves through the heart as it beats. With each squeeze, the valves open and close to keep blood moving forward. In this way, valves keep blood moving as well as possible through the heart. They also prevent backflow.
When the heart relaxes between beats:
-
Oxygen-rich blood from the lungs fills the left atrium.
-
Oxygen-poor blood from the body fills the right atrium.
When the atria beat:
-
The left atrium squeezes. This pushes blood through the mitral valve into the left ventricle.
-
The right atrium squeezes. This pushes blood through the tricuspid valve into the right ventricle.
When the ventricles beat:
-
The left ventricle squeezes. This pushes blood through the aortic valve out to the heart arteries, the brain, and body.
-
The right ventricle squeezes. This pushes blood through the pulmonary valve to the lungs.
Related Articles
Ischemic Cardiomyopathy
Ischemic cardiomyopathy is a disease of the heart muscle.
Understanding Atherosclerosis
Atherosclerosis can start as early as childhood and can lead to many health conditions, including heart disease and stroke.
Heart Valve Problems: Mitral Valve Prolapse
Mitral valve prolapse is the most common heart valve problem. It's usually not serious. With this problem, the valve bulges slightly back into the atrium when it closes. This may allow a tiny amount of blood to leak.
Understanding Atrial Septal Defect (ASD) in Adults
An ASD is a common heart defect that's present at birth. If it's not found until you are an adult, your heart may not be able to pump as much blood.
