heart murmur
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What is a heart murmur?
A heart murmur is a prolonged sound caused by blood circulating through the heart, often described as a swishing or hissing sound after a normal heartbeat, audible via stethoscope. They are generally classified as either innocent (harmless) or abnormal (pathological). Innocent murmurs result from normal blood flow, potentially due to overexertion, fever, or rapid growth phases, and may disappear over time. Abnormal murmurs stem from valve obstructions or blood leakage, causing turbulent flow. Symptoms of abnormal heart murmurs include chest pain, shortness of breath, and fatigue.
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How does a doctor detect a heart murmur?
A doctor typically detects a heart murmur through a stethoscope by performing auscultation, which helps evaluate heart sounds. Murmurs manifest as prolonged swishing or hissing sounds after the normal heartbeat.
These sounds result from vibrations caused by deformed heart valves or turbulent blood flow. The characteristics of a heart murmur, such as its timing, location, duration, intensity, pitch, and quality, are carefully assessed to determine whether it is innocent or abnormal. If needed, the doctor may order an echocardiogram to examine the heart's structure and function.
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What causes a heart murmur?
A heart murmur is a prolonged sound, often described as swishing or hissing, resulting from blood circulating through the heart. There are two types of heart murmurs: innocent and abnormal.
Innocent heart murmurs are harmless, caused by normal blood flow and can be triggered by overexertion, fever, rapid growth, or other factors. Abnormal heart murmurs, however, are pathological. In adults, they can stem from age-related changes, calcium buildup, or diseases affecting the heart. In children, they are usually congenital, arising from structural issues like holes in the heart. Risk factors for heart murmurs in infants include drug use, alcohol use, or infections during pregnancy.
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What is the difference between an innocent and an abnormal heart murmur?
A heart murmur is a prolonged sound of blood circulating through the heart, often heard as a swishing or hissing sound via a stethoscope. Heart murmurs are generally classified as either innocent or abnormal.
Innocent murmurs are harmless, resulting from normal blood flow through the heart's chambers and valves. Factors like physical overexertion, fever, rapid growth in children, or pregnancy can cause these murmurs. They often disappear by adulthood and don't usually require treatment.
Abnormal heart murmurs, however, are pathological. They arise from obstructions or leakage in the heart valves, leading to turbulent blood flow. These murmurs can be congenital (present at birth) or acquired due to age, calcium buildup, or diseases affecting the heart. Symptoms of abnormal heart murmurs include chest pain, shortness of breath, and fatigue.
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What tests can be used to find out more about a heart murmur?
Auscultation with a stethoscope can detect heart murmurs, which are prolonged noises resulting from blood circulating through the heart. If a murmur is detected, further diagnostic tests, such as an electrocardiogram (ECG or EKG) or echocardiogram (which uses ultrasound to examine the heart’s structure and functions), may be performed to determine whether the murmur is innocent or abnormal. The particular sounds that a murmur makes can sometimes reveal the location of the issue in the heart.
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How are heart murmurs treated or managed if they are found to be serious?
If a heart murmur is found to be serious, medical treatment may be necessary if an underlying heart condition is causing the murmur. Diagnostic tests, such as an electrocardiogram (ECG or EKG) or echocardiogram, can help determine if a heart murmur is innocent or abnormal.
Abnormal heart murmurs are caused by either partial obstruction of heart valves or the leakage of blood through them, causing turbulent blood flow through the heart. In adults, they can be acquired due to age, calcium buildup, or diseases affecting the heart. Risk factors for heart murmurs include certain medications during pregnancy, uncontrolled diabetes, anemia, hyperthyroidism, and certain autoimmune disorders.
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heart murmur, condition characterized by prolonged noises made by blood circulating through the heart. A heart murmur is often described as a swishing or hissing sound that occurs after the normal heartbeat sound and is audible through a stethoscope. Heart murmurs are classified into two types: innocent, which are harmless, and abnormal, which are pathological. Such noises may also be the result of vibrations caused by heart valve deformity. Some people are born with heart murmurs, called congenital murmurs. Others develop them at some point in their lives; these are called acquired murmurs.
Types
Innocent murmurs are harmless and are caused by the sound of blood circulating normally through the chambers and valves of the heart. Innocent murmurs can be caused by several factors, including physical overexertion, fever, hyperthyroidism, anemia, pregnancy, and, in children, phases of rapid physical growth. If a physician hears a heart murmur through a stethoscope, they may conduct diagnostic tests, such as an electrocardiogram (ECG or EKG) or echocardiogram (a test that uses ultrasound to examine the heart’s structure and functions), to determine whether a heart murmur is an innocent one. If this is the case, the patient will not require any restrictions on activities or medications. Many people have innocent heart murmurs during childhood, and, for most, these murmurs disappear as they reach adulthood. However, for some they are a lifelong condition.
Abnormal heart murmurs are pathological and are caused by either the partial obstruction of heart valves or the leakage of blood through them, causing turbulent blood flow through the heart. In adults, abnormal heart murmurs can be acquired as a result of age, the buildup of calcium, or diseases that can affect the heart. For example, age can cause heart valves to stiffen or harden. Calcium deposits can also stiffen heart valves, allowing blood to flow backward through the heart. This condition is called calcific aortic valve disease. Endocarditis, an inflammation of the heart lining that can damage heart valves, is caused by bacteria and other microorganisms. Rheumatic fever, a complication of strep throat, can also affect heart valves. Abnormal heart murmurs in children are usually congenital. They are caused by holes in the heart or cardiac shunts, which are structural issues that cause blood to flow irregularly through the atria or ventricles of the heart or through nearby blood vessels.
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Symptoms and risks
Symptoms of abnormal heart murmurs include chest pain; shortness of breath; blue or gray skin; fatigue; swollen liver, neck veins, or ankles; swelling or sudden weight gain; fainting (syncope); persistent cough; heavy sweating; and, in infants, poor appetite and lack of growth. Abnormal heart murmurs occur with many different heart conditions, and the particular sounds that a murmur makes can sometimes reveal the location of the issue in the heart. Medical treatment may be necessary if a heart condition is causing an abnormal murmur.
Risk factors that may cause heart murmurs in infants include the use of alcohol, drugs, narcotics or certain medications during pregnancy and uncontrolled diabetes or rubella (German measles) during pregnancy. In adults, certain medical conditions are risk factors for heart murmurs, such as anemia; hyperthyroidism; pulmonary hypertension; certain autoimmune disorders, such as lupus and rheumatoid arthritis; and cardiomyopathy.