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Heart Failure |
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Causes of Heart Failure
Common causes of heart failure include:
Damage from a prior heart attack, which also is called a myocardial infarction -- A heart attack occurs when an artery that supplies blood to the heart is blocked so that no oxygen reaches the heart muscle. When this happens, part of the heart "dies." The medical term for the area of dead muscle is called the "infarct." The remaining, healthy tissue must take over the job of pumping blood, an extra burden that may weaken the heart's pumping ability.
Coronary artery disease (CAD) or clogged heart vessels -- Like all the organs and tissues of the body, the heart needs oxygen and other nutrients carried by the blood to remain healthy. When the blood vessels become narrow or clogged so that not enough blood reaches the heart, damage is done to the heart muscle, which, in turn, may affects it ability to pump blood efficiently. The most common cause of CAD is arteriosclerosis, which is sometimes called "hardening of the arteries," a condition in which cholesterol and fatty deposits called plaque build up in the arteries. CAD also may be caused by blood clots that lodge in the arteries and interfere with blood flow.
Heart rhythm disorders or arrhythmia -- When the heartbeat is too fast, too slow or irregular, the heart may not be able to pump enough blood. Once the underlying problem causing the irregular heartbeat is treated, the symptoms of heart failure may go away before significant damage is done to the heart muscle.
Alcohol and drug abuse -- Excessive use of alcohol or drugs such as cocaine and amphetamines can damage the heart. These substances can damage the cells of the heart or prevent them from functioning, or constrict the blood vessels of the heart, resulting in raised blood pressure and heart rate. These stresses can lead to heart failure or other heart disease. Some environmental toxins and prescriptions drugs also can contribute to the problem.
Abnormal heart valves -- The valves that open and close to allow
blood to pass between the chambers of the heart may
be damaged by disease or infection. Sometimes, heart
valve defects are present at birth, called congenital.
If the valves don't open or close completely with each
heartbeat, the heart has to pump harder to keep the
blood moving. If the workload becomes too great, heart
failure can develop.
Heart muscle disease (cardiomyopathy) or inflammation (myocarditis) -- Any damage to the heart muscle itself increases the risk of heart failure. Heart muscle disease or infection may be increased by birth defects, drug or alcohol abuse, bacterial or viral infections, or by other, unknown causes.
Heart defects present at birth, called congenital heart disease -- If the heart and its chambers don't form correctly in the developing fetus, the normal parts of the heart must make up for the defects by working harder. Over time, the added stress may cause healthy structures to fail.
Diabetes -- Diabetes tends to increase the levels of cholesterol and triglycerides - unhealthy fats that contribute to coronary artery disease. People with diabetes also are more likely to be overweight and have high blood pressure. These factors must be carefully monitored and controlled because they put extra strain on the heart and can lead to heart failure, as well as to other cardiovascular diseases such as heart attack and strokes.
High blood pressure or hypertension -- Uncontrolled high blood pressure doubles a person's risk of developing heart failure. If the pressure created by blood flow through the vessles of the circulatory system is too high, the heart has to pump harder to keep the blood circulating. Over time, the extra burden can weaken the heart and eventually contribute to heart failure.
Sometimes, an otherwise healthy heart may temporarily have trouble keeping up with the body's need for oxygen and other nutrients carried by the blood because of problems unrelated to the cardiovascular system. These problems are less common than other causes for heart failure, but it is important to monitor heart function in people who have:
Anemia or an abnormally low number of red blood cells -- It is the job of the red cells to carry oxygen needed to maintain life in the body's cells. If there are not enough of these cells, the heart pumps at a faster rate to circulate the smaller number of red cells quickly enough to supply the body's oxygen need. Over time, the extra burden may lead to heart damage.
Thyroid disorders, such as overactive thyroid
gland or hyperthyroidism -- The thyroid gland affects the rate at which the body metabolizes food and other substances. If the thyroid is overactive, the body works at a faster pace and the heart may be overworked as it adjusts to keep up with the increased demand for oxygen and other nutrients, and the increased rate at which waste products build up that must be picked up by the circulating blood and carried to the kidneys, liver and elsewhere to be processed and excreted.
Lifestyle factors associated with heart disease in general also may contribute to heart failure, including:
- High cholesterol
- Cigarette smoking
- A family history of heart failure or other heart disease
Sometimes, there is no known cause for heart failure.
More Information:
Reviewed by health care specialists at UCSF Medical Center.
Last updated May 8, 2007
This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.
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