The Heart

The heart is a muscle that pumps blood throughout your body. The blood carries oxygen and nutrients that your body needs to work correctly. For the heart to be able to function properly, it also needs a constant supply of oxygen-filled blood.The vessels that supply this blood to the heart are called coronary arteries become narrowed, treatment is usually required to restore blood flow and the vital supply of oxygen to the heart.
A healthy heart pumps blood throughout the body all started by an electrical signal. A healthy heart has an intact electrical system and a strong mechanical arteries.(pumping) system. By knowing the differences between a plumbing problem (heart attack), an electrical problem (arrhythmias such as a heart rate that,s too slow or too fast), and a pumping problem (heart failure) you may understand your own heart,s condition more clearly.
And remember, your doctor and heart nurse are your best resources for information.

Structure of the Heart

The heart is a hollow, muscular organ, about the size of your fist and has a mass of between 250 grams and 350 grams. It is located behind and slightly to the left of the breastbone.
The heart comprises of four chambers: Two smaller, upper chambers (called right and left atrium) and two larger, lower pumping chambers (the right and left ventricle). These four chambers work together in powerful contractions (heartbeats) to circulate blood to entire body..

Blood flow through the Heart

The right half of the heart circulates blood through the lungs to be refreshed with oxygen. Then the oxygen-rich blood returns to the left half of the heart and is pumped to the rest of the body.

Function of the Heart

The function of the heart is simple. It keeps blood circulating throughout the body by:

  • Pumping blood through your lungs to make certain that the blood supply is constantly refreshed with oxygen and carbon dioxide is removed, and
  • Pumping blood through your body to meet its demand for oxygen and nutrients.

The heart is an amazing pump. An average person has 40 million heartbeats a year. Through powerful contractions (heartbeats) the heart circulates your entire blood supply each and every minute. With each beat, the right upper and lower chambers of the heart gather blood from the body and send it to the lungs to pick up fresh oxygen. At the same time, the left upper and lower chambers of the heart gather blood carrying oxygen from the lungs and pump it out to the body.

The heart is very sensitive to your body's needs, adjusting its rate of pumping to the demand of your body's cells. For example, with a faster heart rate during strenuous exercise, the heart can increase the amount of blood up to four times the amount it pumps at rest, within only a matter of seconds.

The Circulatory System

Your circulatory system ensures every cell in your body receives a constant supply of blood. The blood delivers nutrients and oxygen to your cells and removes waste products and carbon dioxide. The heart ensures that blood flows constantly by pumping it through the blood vessels. Blood vessels are tubes of all different sizes that transport blood to and from the heart. Together, the heart and blood vessels make up the circulatory system.

Blood Vessels

The blood vessels - arteries, capillaries, and veins - are an extensive network of elastic tubes that carry blood to and from the heart and throughout the body. The blood vessels are the transportation system of the human body.


ARTERIES are thick, muscular tubes that carry blood away from the heart. All arteries transport oxygen rich blood except for the pulmonary artery. Pulmonary artery carries deoxygenated blood from the heart to the lungs.
Coronary arteries are blood vessels on the outside (surface) of the heart that provides oxygen-filled blood to the heart.


CAPILLARIES are tiny vessels whose walls are so thin that oxygen, nutrients, and waste products flow through them. The network of capillaries is so extensive that if they were laid end to end, they would extend about 60,000 miles. Capillaries nourish virtually every cell in the body. This is amazing when you consider that the average person has about 500 trillion cells!
After flowing through the capillaries and exchanging oxygen and nutrients for waste and carbon dioxide, the blood supply needs to be refreshed. Your blood must flow back to the heart.


VEINS are thinner, muscular tubes that carry blood into the heart. All veins transport deoxygenated blood except for the pulmonary vein. Pulmonary veins carry oxygen rich blood from the lungs to the heart.
Remarkably, the heart and blood vessels circulate blood throughout the body more than 100,000 times per day!

Do you or someone you know suffer from any of these symptoms

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