Strong Heart and Vascular Center
How the Heart Works
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The heart is basically a pump, made up of specialized muscle tissue called the myocardium. The heart's primary function is to pump blood throughout the body so the body's tissues can receive oxygen and nutrients and have waste substances taken away.
Fueling Your Heart
Like any pump, the heart requires fuel in order to work. The myocardium requires oxygen and nutrients, just like any other tissue in the body. However, the blood that passes through the heart's chambers is only passing through on its trip through the body; this blood does not give oxygen and nutrients to the myocardium. The myocardium receives its oxygen and nutrients from the coronary arteries. The coronary arteries lie on the outside of the heart and supply oxygenated blood to the heart tissue.
The Heart's Four Chambers
The heart has four pumping chambers: two upper chambers, called atria, and two lower chambers, called ventricles. The right atrium pumps blood into the right ventricle, which then pumps the blood into the lungs, where wastes such as carbon dioxide are given off and oxygen and other nutrients are taken into the blood.
The Flow
From the lungs, the blood flows back into the left atrium, is pumped into the left ventricle, then is pumped through the aorta out to the rest of the body and the coronary arteries. When the atria are pumping, the ventricles are relaxed in order to receive the blood from the atria. Once the atria have pumped their entire blood load into the ventricles, they relax while the ventricles pump the blood out to the lungs and to the rest of the body.
In order to keep the blood flowing forward during its journey through the heart, there are valves between each of the heart's pumping chambers:
- Tricuspid valve—Located between the right atrium and the right ventricle.
- Pulmonary (or pulmonic) valve—Located between the right ventricle and the pulmonary artery.
- Mitral valve—Located between the left atrium and the left ventricle.
- Aortic valve—Located between the left ventricle and the aorta.
What Can Go Wrong