1. The Heart

Cardiovascular disease can take many forms: high blood pressure, coronary artery disease, valvular heart disease, stroke, or rheumatic fever/rheumatic heart disease. According to the World Health Organization, cardiovascular disease causes 17.5 million deaths in the world each year.

 

Cardiovascular disease is responsible for half of all deaths in the World and other developed countries, and it is a main cause of death in many developing countries as well. Overall, it is the leading cause of death in adults.

 

In the United States, more than 80 million Americans have some form of cardiovascular disease.

 

About 2400 people die every day of cardiovascular disease. Cancer, the second largest killer, accounts for a little more than half as many deaths.

 

Coronary artery disease, the most common form of cardiovascular disease, is the leading cause of death in America today. But thanks to many studies involving thousands of patients, researchers have found certain factors that play an important role in a person's chances of developing heart disease. These are called risk factors.

 

Risk factors are divided into two categories: major and contributing. Major risk factors are those that have been proven to increase your risk of heart disease. Contributing risk factors are those that doctors think can lead to an increased risk of heart disease, but their exact role has not been defined.

 

The more risk factors you have, the more likely you are to develop heart disease. Some risk factors can be changed, treated, or modified, and some cannot. But by controlling as many risk factors as possible through lifestyle changes, medicines, or both, you can reduce your risk of heart disease.

 

Your heart works as a pump that pushes blood to the organs, tissues, and cells of your body. Blood delivers oxygen and nutrients to every cell and removes the waste products made by those cells.

 

Blood is carried from your heart to the rest of your body through a complex network of arteries, arterioles, and capillaries. Blood is returned to your heart through venules and veins.

The heart weighs between 7 and 15 ounces and is a little larger than the size of your fist. By the end of a long life, a person's heart may have beat (expanded and contracted) more than 3.5 billion times. In fact, each day, the average heart beats 100,000 times, pumping about 2,000 gallons of blood.           

 

Your heart has 4 chambers. The upper chambers are called the left and right atria, and the lower chambers are called the left and right ventricles. A wall of muscle called the septum separates the left and right atria and the left and right ventricles. The left ventricle is the largest and strongest chamber in your heart. Its half-inch thick chamber walls have enough force to push blood into your body.

 

2. How does the heart receive notice to beat?

The heart has its own electrical system, like a battery. This special electrical conduction system tells it to beat (contract) in a regular, coordinated and effective way. The electrical impulse starts in the right atrium. The impulse spreads throughout the atria, causing them to contract. Next, the impulse moves to the ventricles. As the impulse travels down the fibers, the ventricles contract. The cycle then repeats itself. Your heart rate may still change depending on physical demands, stress, or hormonal factors. At night the heart will beat slowly, and during exercise it will beat faster.

 

 

"'The initiative consists of two phases: offer development and demand stimulation."

 

 

 

 

 

 

 

 

3.What is an arrhythmia?

The regular cycle of atria contractions, followed by ventricular contractions, pumps blood effectively out of the heart.

Problems may occur anywhere in the electrical system and interfere with effective pumping of blood.

The heart may beat too fast , too slow , or irregularly.

These abnormal beats are known as arrhythmias. The arrhythmia may come from either the top or the bottom chambers. During an arrhythmia a patient may notice different sensations: he may feel nothing, the heart pounding or fluttering, a heaviness in the chest, shortness of breath. However, when the arrhythmia is so severe that the heart is not able to pump the blood efficiently, the patient may experience a fainting spell and even die. This can happen if the heart beats too slow or too rapidly.

4. What is the treatment for an arrhythmia?

Special studies of the heart's electrical system may be needed to find the type of arrhythmia. Treatment for arrhythmias is based on their type and any difficulties they cause. Treatment may include medication, cardiac catheterization, placement of a pacemaker, or even surgery.

5. How do I know if I have an arrhythmia?

There are different tests, but the doctor will probably start by asking a few questions, listening to your heart and doing an electrocardiogram.

6. Can I inherit an arrhythmia from my parents?

There are some arrhythmias that may be inherited, like long QT, Brugada syndrome and atrial fibrillation. This means that if your parents have the arrhythmia you have a higher chance of also having it.