OverviewWhat is the heart?The heart is a fist-sized organ that pumps blood throughout your body. It's the primary organ of your circulatory system. Show
Your heart contains four main sections (chambers) made of muscle and powered by electrical impulses. Your brain and nervous system direct your heart’s function. What does a heart diagram look like?The inside and outside of your heart contain components that direct blood flow: Inside of the Heart Outside of the Heart FunctionWhat is the heart’s function?Your heart’s main function is to move blood throughout your body. Your heart also:
How does your heart work with other organs?Your heart works with other body systems to control your heart rate and other body functions. The primary systems are:
AnatomyWhere is your heart located?Your heart is located in the front of your chest. It sits slightly behind and to the left of your sternum (breastbone). Your ribcage protects your heart. What side is your heart on?Your heart is slightly on the left side of your body. It sits between your right and left lungs. The left lung is slightly smaller to make room for the heart in your left chest. How big is your heart?Everyone’s heart is a slightly different size. Generally, adult hearts are about the same size as two clenched fists, and children’s hearts are about the same size as one clenched fist. How much does your heart weigh?On average, an adult’s heart weighs about 10 ounces. Your heart may weigh a little more or a little less, depending on your body size and sex. What are the parts of the heart’s anatomy?The parts of your heart are like the parts of a house. Your heart has:
Heart wallsYour heart walls are the muscles that contract (squeeze) and relax to send blood throughout your body. A layer of muscular tissue called the septum divides your heart walls into the left and right sides. Your heart walls have three layers:
The epicardium is one layer of your pericardium. The pericardium is a protective sac that covers your entire heart. It produces fluid to lubricate your heart and keep it from rubbing against other organs. Heart chambersYour heart is divided into four chambers. You have two chambers on the top (atrium, plural atria) and two on the bottom (ventricles), one on each side of the heart.
Heart valvesYour heart valves are like doors between your heart chambers. They open and close to allow blood to flow through. The atrioventricular (AV) valves open between your upper and lower heart chambers. They include:
Semilunar (SL) valves open when blood flows out of your ventricles. They include:
Blood vesselsYour heart pumps blood through three types of blood vessels:
Your heart receives nutrients through a network of coronary arteries. These arteries run along your heart’s surface. They serve the heart itself.
Electrical conduction systemYour heart’s conduction system is like the electrical wiring of a house. It controls the rhythm and pace of your heartbeat. It includes:
Your heart also has a network of electrical bundles and fibers. This network includes:
Conditions and DisordersWhat conditions and disorders affect the human heart?Heart conditions are among the most common types of disorders affecting people. In the United States, heart disease is the leading cause of death for people of all genders and most ethnic and racial groups. Common conditions that affect your heart include:
CareHow can I keep my heart healthy?If you have a condition that affects your heart, follow your healthcare provider’s treatment plan. It’s important to take medications as prescribed. You can also make lifestyle changes to keep your heart healthy. You may:
Frequently Asked QuestionsWhat should I ask my doctor about my heart?You may want to ask your healthcare provider:
A note from Cleveland Clinic Your heart is the primary organ of your circulatory system. It pumps blood throughout your body, controls your heart rate and maintains blood pressure. Your heart is a bit like a house. It has walls, rooms, doors, plumbing and an electrical system. All the parts of your heart work together to keep blood flowing and send nutrients to your other organs. Conditions that affect your heart are some of the most common types of conditions. Ask your healthcare provider how you can improve your heart health. |