The Heart


Introduction

You need your heart for all your body needs. It pumps about 2000
gallons of blood a day. It takes about 20 seconds for blood to reach every
cell in the body. An artery carries blood out from the heart. A vein carries
blood back to the heart. An average adult heart weighs about 10-13 ounces (300
to 350 grams). The rate which the heart pumps varies depending on what your
doing. When at rest the heart pumps more slowly. When you run the heart rate
increases to provide muscles and other tissues with additional oxygen they need.
The typical heart rate is 72 beats per minute. Each beat gives out 2-3 ounces
of blood pumped into the arterial system. At this heart rate it beats about
104,000 times a day. The Superior and Inferior are the biggest veins in the
body. The Superior is really the biggest. These veins have a lot of carbon
dioxide and have oxygen-poor blood. The aorta is the biggest artery in the
whole body. Which will be covered in the report. The pulmonary vein takes the
blood out of the heart and takes it to the lungs.

Today we will talk about many different parts of the heart: The Three
Layers of Muscle, Atriums, Ventricles, Systole and Diastole, Treatments for the
Heart, Valves, and many Diseases.

The Three Layers of Muscle

The heart has three layers of a muscular wall. A thin layer of tissue,
the pericardium covers the outside, and another layer, the endocardium, lines
the inside. The myocardium is the middle layer and is the biggest of all.
Myocardial Infarction is a disease later read about in this report. The
pericardium is a fibrous sac which is very smooth lining. In the space space
between the pericardium and epicardium is a small amount of fluid. This fluid
makes the movement of the heart muscles smooth. Myocardium is the heart muscle
itself.

Atriums

The right atrium is a low pressure pump that moves blood into the right
ventricle through the tricuspid valve. The atria are the two upper chambers of
the heart. The right atrium receives blood from the veins which is low in
oxygen and high in carbon dioxide; this blood is then transferred to the right
lower chamber, or right ventricle, and is pumped into the lungs.

Ventricles

The ventricle is a muscular chamber that pumps blood out of the heart
and into the circulatory system.

Right Ventricle

The right ventricle has a thicker and stronger muscular wall than the
right atrium. The right ventricle pumps the oxygen-poor blood through the
pulmonic valve into the lungs where blood gives up carbon dioxide it has
carried from tissues. At the same time blood absorbs oxygen. From the lungs
pumping action moves blood to a receiving chamber on the other side of the
heart. The left atrium, gently pumps the blood to the left ventricle through
the mitral valve.

Left Ventricle

The left ventricle gives a powerful pumping action to send the oxygen
enriched in blood into the aorta. The aorta is the principal artery which
subdivides and delivers the blood to the body\'s tissues including brain, organs,
and extremities.
Systole and Diastole

Systole is the contraction of the ventricles of the heart which forces
blood out. Diastole is the relaxation of ventricles to allow blood to enter.

Treatments for the Heart

Angioplasty is a technique used to clear arteries that have become
blocked with fatty deposits. Angiography is used to x-ray the blood vessels.

Valves

In the heart there are two valves that prevent backflow of blood from
the ventricles into the atria. On the right side of the heart is the tricuspid
valve, composed of three flaps of tissue; on the left is the two-piece mitral
valve.

DISEASES

Congenital Disorders

Range of minor to serious congenital disorders are very evident at or
shortly after birth.

Ventricular Septal Defect

Ventricular Septal Defect is most common for heart malformation. An
infant born with a defect has an opening between the lower chambers (ventricles)
of its heart so there is an increased blood flow from the left side to the
right side because the left side has more pressure than right side. The lungs
at this state are under very high in pressure. Treatment for this disease
depends on it size of defect. About 30%-50% of small defects close
spontaneously during the first year of life.

Artrial Septal Defect

Atrial Septal defect is a opening which is high in the heart between the
upper chambers (atria). This disease is more common in female infants than in
male infants, and it often occurs with children who have Down