Cardiomyopathy

Cardiomyopathy refers to a weakened heart muscle that is sometimes unable to pump enough blood through the heart and to the body. There are three types of cardiomyopathies. They are congestive, hypertrophic, and restrictive cardiomyopathies.

Dilated (congestive)

Congestive cardiomyopathy is the most common form. The exact cause is not known. Factors that may be associated with it are high alcohol intake, nutritional deficiencies, electrolyte or hormonal disorders, viral diseases, coronary artery disease, or heredity.

The main feature of congestive cardiomyopathy is that the muscle fibers of the heart are damaged. Therefore, the heart has trouble pumping blood to the body as well as it once did. Because the heart has to work so hard to pump the blood, the heart muscle becomes thinned and stretched.

Hypertrophic

Hypertrophic cardiomyopathy is the second most common form of the cardiomyopathies. This type is often referred to as IHSS (Idiopathic Hypertrophic Subaortic Stenosis). Generally, IHSS appears to be inherited from blood relatives who may or may not have symptoms of the disease process.

Restrictive

Restrictive cardiomyopathy is a rare form. The cause is often unknown. There are, however, a number of hormonal disorders that may cause this condition. The disease results in a thickened inner lining of the heart muscle. The heart becomes very rigid, so it doesn't contract properly.

Why cardiomyopathies are treated as heart failure
The heart is a four-chambered muscular organ that pumps blood through the body. Cardiomyopathies affect the heart's ability to pump blood. Whatever the type of cardiomyopathy, the heart muscle is weakened and has trouble pumping blood through the body as easily as it once did. This condition may result in congestive heart failure.

Congestive Heart Failure

Whenever the heart cannot keep up with the body's needs, a person may be diagnosed with congestive heart failure. The degree of heart failure can range from mild to severe.

The heart is a muscle, about the size of a person's fist. It is divided into two halves. The right half receives blood from the body and pumps it to the lungs where it obtains oxygen. The left half receives the oxygen-rich blood from the lungs and pumps it to the rest of the body.

The picture below shows the right and left sides of the heart. Veins carry blood to the heart and arteries carry blood away from the heart. Valves direct blood flow through the heart chambers.

A person can have one or both kinds of heart failure:

Left heart failure-The left side of the heart is weak and cannot pump out as much blood as it receives from the right side of the heart. As a result, blood backs up in the lungs.
Right heart failure-The right side of the heart cannot pump as much blood to the lungs as it receives from the body. As a result, fluid backs up in the body tissues. Sometimes the cause of heart failure is unknown, but several of the known causes are described below. Your doctor will talk with you about the cause of your heart failure.

Atherosclerosis

Atherosclerosis is the build-up of fatty deposits (plaque) on the walls of the coronary arteries. This plaque can block the flow of blood to the heart muscle. When the heart muscle is deprived of some of the oxygen and nutrients it needs, it may not pump as well as it should.

Heart Attack

A heart attack means that part of the heart muscle has died from lack of blood and oxygen. This area is no longer able to pump with the rest of the heart muscle. Depending upon the amount of damage, some degree of heart failure can occur.

Hypertension (High Blood Pressure)

When the heart pumps blood through the arteries, the blood exerts pressure against the walls of those arteries. When this pressure is too high, the heart must work harder to move blood through the arteries. Over a long period of time, the heart muscle can become weakened.

Valves are structures that allow blood to flow through the heart chambers in one direction. They open to let blood flow through and snap shut to keep blood from flowing backward. A narrowed or leaking valve can make the heart work harder and eventually result in a weakened heart muscle.

Other Causes of Heart Failure

Chronic lung disease, heart rhythm problems, and congenital heart defects (defects present at birth).

The Most Common Symptoms of Heart Failure

You may have some or all of these symptoms, depending upon the condition of your heart.

Trouble breathing: When the heart isn't pumping as well as it should, some of the blood may back up rather than move forward. Blood can then build up in the lungs and cause trouble breathing during activities or even at rest. Some people are unable to sleep flat in bed or are awakened from sleep because of trouble breathing.

Fatigue: Oxygen gets into the blood through the lungs. But a build-up of blood in the lungs can reduce the amount of oxygen getting into the blood. This lower oxygen content, combined with the heart's inability to pump normally, can cause a person to feel tired or weak.

Swelling in the feet, ankles, legs or abdomen: When the heart is weakened, fluid can also build up or be retained in body tissues. This may result in swelling � usually in the feet, ankles, legs, or abdomen.

Abnormal weight gain: When the body is holding fluid, body weight will increase. A weight gain of two to five pounds within a few days is not normal (if eating habits are the same) and may be a sign of fluid retention.

Other less common symptoms of heart failure include:

frequent dry cough
loss of appetite
nausea or vomiting
abdominal tenderness

The goals in treating heart failure are to strengthen the heart muscle and to lessen the demands placed on the heart.

Ask your doctor or nurse about an exercise or walking program to help build your tolerance for activity. Do only what is prescribed for you. Listen to your body and don't push it if you feel too tired or short of breath. Keep a log of your exercise to show your doctor.
Schedule a rest period after any activity that makes your heart work hard, such as exercise, meals, or heavy housework.
Sit rather than stand whenever you can during daily activities.
Avoid extremes of temperature. Your heart works harder when you are very hot or very cold.
Avoid excess eating or drinking, as this can put a strain on the heart.
Reduce your sodium intake. Most people take in more sodium than they need because there is so much of it in prepared foods.
Lose excess weight. Extra pounds can make the heart work harder.

Your doctor may prescribe one or more of the following for you. Be sure you are given written instructions about your medications.

A diuretic (water pill), to help rid excess sodium and water from your body. If you take a water pill, you may notice that you're passing more urine, especially at night. If you feel dizziness, weakness, or leg cramping while you are taking this pill, tell your doctor (the dosage may need to be changed). Taking a water pill may cause you to lose some potassium, which is an important mineral. Your doctor may prescribe a potassium medication for you, or you may be asked to eat more foods that are rich in potassium.
Digitalis, to strengthen your heart muscle so that more blood is pumped to the body with each heartbeat. Tell your doctor if you have a loss of appetite, nausea, vision problems, or irregular heartbeats while you are taking this pill.
A vasodilator, to widen and relax the walls of the blood vessels. This makes it easier for the heart to pump blood through the vessels.
Ace inhibitors prevent the heart muscle from becoming weaker.

A word of caution: Many over-the-counter medicines contain sodium or may interact with other medicines you take. Check with your doctor or pharmacist before taking any of these.

Cardiac Resynchronization (Biventricular Pacing) Therapy for CHF

A new treatment option for moderate to severe congestive heart failure is available and is called cardiac resynchronization therapy or biventricular pacing. This therapy is intended for heart failure patients with ventricular dysynchrony (definition follows). A pacemaker device designed specifically for this problem provides simultaneous pacing stimulation of both lower heart chambers or ventricles (only the right ventricle is stimulated in traditional pacing systems) and should help the heart pump blood more efficiently.

Ventricular dysynchrony occurs when the two ventricles beat separately, reducing the efficiency of pumping blood to the body. Normally, the two ventricles beat at the same time and are "synchronized." Ventricular dysynchrony occurs in up to 30% of heart failure patients and can be detected on a routine electrocardiogram. Cardiac resynchronization sends electrical impulses to both ventricles to make them beat together. The pacemaker device is placed under the skin in the chest and connected to three soft insulated wires that are inserted through the veins into the heart. Most patients have shown significant improvement in exercise tolerance, quality of life and reduced hospitalization.

Candidates for cardiac resynchronization therapy include patients with advanced heart failure refractory to medication and ventricular dysynchrony.

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