Items Tagged With heart disease

What Is Normal Heart Rhythm?

The heart has four chambers, or areas. During each heartbeat, the two uppers chambers (atria) contract, followed by the two lower chambers (ventricles). This action is directed by the heart's electrical system.

The electrical impulse begins in an area called the sinus node, located in the upper part of the right atrium. When the sinus node fires, an impulse of electrical activity spreads through the right and left atria, causing them to contract, forcing blood into the ventricles.

Then the electrical impulses travel in an orderly manner to another area called the atrioventricular (AV) node and HIS-Purkinje network. The AV node is the electrical bridge that allows the impulse to go from the atria to the ventricles. The HIS-Purkinje network carries the impulses throughout the ventricles. The impulse then travels through the walls of the ventricles, causing them to contract. This forces blood out of the heart to the lungs and the body. The pulmonary veins empty oxygenated blood from the lungs to the left atrium. A normal heart beats in a constant rhythm -- about 60 to 100 times per minute at rest.

What Is Atrial Fibrillation?

Atrial fibrillation (AF or Afib) is the most common type of irregular heartbeat. It is found in about 2.2 million Americans. It increases with age. If you have AF, the impulse does not travel in an orderly fashion through the atria. Instead, many impulses begin simultaneously and spread through the atria and compete for a chance to travel through the AV node.

The firing of these impulses results in a very rapid and disorganized heartbeat. The rate of impulses through the atria can range from 300 to 600 beats per minute. Luckily, the AV node limits the number of impulses it allows to travel to the ventricles. As a result, the pulse rate is often less than 150 beats per minute, but this is often fast enough to cause symptoms. The AV node limits the number of impulses that travel to the ventricles.

What Are the Symptoms of Atrial Fibrillation?

You may have atrial fibrillation without having any symptoms at all. If you have symptoms, they may include:

• Heart palpitations (a sudden pounding, fluttering, or racing feeling in the chest).
• Lack of energy; feeling over-tired.
• Dizziness (feeling faint or light-headed).
• Chest discomfort (pain, pressure, or discomfort in the chest).

Shortness of breath (difficulty breathing during normal activities or even at rest).

What Causes Atrial Fibrillation?

Atrial fibrillation is associated with many conditions, including:

• High blood pressure
• Coronary artery disease (hardening of the heart arteries)
• Heart valve disease
• Having undergone heart surgery
• Chronic lung disease
• Heart failure
• Cardiomyopathy (disease of heart muscle that causes heart failure)
• Congenital (present at birth) heart disease
• Pulmonary embolism (blood clot in lungs)

When you think of heart disease, usually people think of coronary artery disease (narrowing of the arteries leading to the heart), but coronary artery disease is just one type of cardiovascular disease.

Cardiovascular disease includes a number of conditions affecting the structures or function of the heart. They can include:

• Coronary artery disease (including heart attack)
• Abnormal heart rhythms or arrythmias
• Heart failure
• Heart valve disease
• Congenital heart disease
• Heart muscle disease (cardiomyopathy)
• Pericardial disease
• Aorta disease and Marfan syndrome
• Vascular disease (blood vessel disease)

Cardiovascular disease is the leading cause of death for both men and women in the U.S. It is important to learn about your heart to help prevent heart disease. And, if you have cardiovascular disease, you can live a healthier, more active life by learning about your disease and treatments and by becoming an active participant in your care.

Coronary Artery Disease

Coronary artery disease (CAD) is atherosclerosis, or hardening, of the arteries that provide vital oxygen and nutrients to the heart.

Abnormal Heart Rhythms

The heart is an amazing organ. It beats in a steady, even rhythm, about 60 to 100 times each minute (that's about 100,000 times each day!). But, sometimes your heart gets out of rhythm. An irregular or abnormal heartbeat is called an arrhythmia. An arrhythmia (also called a dysrhythmia) can involve a change in the rhythm, producing an uneven heartbeat, or a change in the rate, causing a very slow or very fast heartbeat.

Heart Failure

The term "heart failure" can be frightening. It does not mean the heart has "failed" or stopped working. It means the heart does not pump as well as it should.

Heart failure is a major health problem in the U.S., affecting nearly 5 million Americans. About 550,000 people are diagnosed with heart failure each year. It is the leading cause of hospitalization in people older than 65.

Heart Valve Disease

Your heart valves lie at the exit of each of your four heart chambers and maintain one-way blood-flow through your heart.

Examples include mitral valve prolapse, aortic stenosis and mitral valve insufficiency.

Congenital Heart Disease

Congenital heart disease is a type of defect in one or more structures of the heart or blood vessels that occur before birth.

It affects about 8 out of every 1,000 children. Congenital heart defects may produce symptoms at birth, during childhood and sometimes not until adulthood.

In most cases scientists don't know why they occur. Heredity may play a role as well as exposure to the fetus during pregnancy to certain viral infections, alcohol or drugs.

Cardiomyopathies

Cardiomyopathies are diseases of the heart muscle itself. People with cardiomyopathies have hearts that are abnormally enlarged, thickened and/or stiffened. As a result, the heart's ability to pump blood is weakened. Without treatment, cardiomyopathies worsen over time and often lead to heart failure and abnormal heart rhythms.