A heart murmur is an extra or unusual sound that a healthcare provider can hear while listening to the heart with a stethoscope. This sound is often described as a whooshing or swishing noise. The noise originates from turbulent or choppy blood flow within the heart or nearby blood vessels. While the discovery of an unusual sound in your heart can be alarming, most heart murmurs are harmless and do not indicate a serious health problem. However, because some murmurs can signal an underlying condition, a medical evaluation is necessary to determine the cause and decide if further action is required.
Understanding the Two Categories of Murmurs
Heart murmurs are categorized as innocent (or functional) murmurs and abnormal (or pathological) murmurs. This distinction is critical because it dictates the level of concern and the need for medical intervention.
An innocent murmur arises when blood flows more rapidly than usual through a heart that is otherwise completely normal, creating a temporary turbulence that produces the sound but indicating no underlying heart disease. Conversely, an abnormal murmur signals an actual defect in the heart’s structure, such as an issue with the valves or a hole in the heart wall. The intensity or loudness of the murmur does not always correlate with its severity, meaning a quiet murmur can sometimes be more concerning than a loud one.
When Reassurance is Warranted: The Innocent Murmur
Innocent heart murmurs are incredibly common, especially during childhood. These murmurs are produced when the volume or velocity of blood flow increases, which temporarily makes the flow more turbulent. The heart itself is structurally sound, and the murmur does not pose any health risk or require treatment.
For instance, an innocent murmur may appear during a growth spurt, a fever, or following vigorous exercise, all of which temporarily increase the heart’s output. These harmless sounds frequently disappear as a child grows older, though some may persist into adulthood.
A key characteristic of an innocent murmur is that it is often sensitive to changes in body position, sometimes becoming softer or disappearing entirely when a person sits up or stands. Crucially, an innocent murmur is never accompanied by any other symptoms or signs of distress. It is simply a physical finding made by the doctor during a routine examination of a healthy individual.
Critical Symptoms and Structural Causes for Concern
A heart murmur is concerning when accompanied by persistent symptoms. Immediate medical attention is necessary if you experience shortness of breath, especially with physical exertion, or unexplained chronic fatigue.
Other concerning symptoms include episodes of dizziness or fainting, persistent chest pain, or a bluish tinge to the skin or lips, known as cyanosis. In infants, a failure to gain weight normally or difficulty feeding can be a significant indicator of a pathological murmur.
The structural issues causing abnormal murmurs primarily involve the heart’s four valves or the septa, the walls separating the heart’s chambers. Valve problems fall into two main categories: stenosis, where a valve becomes stiff and narrowed, restricting blood flow, or regurgitation, where a valve does not close completely, causing blood to leak backward. Abnormal blood flow can also be caused by septal defects, such as a hole in the wall between the heart’s upper or lower chambers.
Diagnostic Procedures and Management Overview
If a healthcare provider hears a suspicious murmur or notes concerning symptoms, a complete evaluation is initiated. The most definitive and widely used non-invasive test is the echocardiogram, which uses sound waves to create moving images of the heart. This ultrasound allows a specialist to visualize the heart’s valves, chambers, and blood flow patterns in detail, confirming whether a structural issue is present.
Other tests may include an electrocardiogram (ECG) to measure the heart’s electrical activity or a chest X-ray to check for an enlarged heart. Once a diagnosis is made, management is tailored to the cause. Innocent murmurs require no treatment.
For abnormal murmurs, treatment depends on the specific defect and its severity. Mild structural problems may only require careful monitoring over time. More significant conditions may be managed with medications to improve heart function, such as those that control blood pressure or heart rate. In severe cases, surgical intervention may be necessary to repair or replace a faulty heart valve or to close a congenital defect.