A heart murmur is an extra or unusual sound heard while listening to the heartbeat. It is a finding to interpret, not the name of a disease. Some murmurs are harmless; others lead to testing for a valve problem or another structural heart condition.
The sound needs a clinical context
An innocent murmur comes from blood moving through a heart without a structural problem. These murmurs are common in children and may change with growth or activity. An abnormal murmur can occur with a narrowed valve, called stenosis, or a valve that leaks backward, called regurgitation. Congenital heart differences can also produce murmurs. The American Heart Association's murmur explanation distinguishes these possibilities.
A clinician considers where the sound is heard, its timing and quality, the person's age, symptoms, examination, and history. A systolic murmur occurs while the heart contracts; a diastolic murmur occurs while it relaxes between beats. Loudness is one clue, not a complete assessment of the underlying problem.
When a clinician has established that a child's murmur is innocent, it generally needs no medicine or activity restriction. That reassurance depends on the assessment. It should not be applied to an unexplained new murmur simply because the person feels well.
Listening may be followed by imaging
Evaluation usually starts with questions and an examination. Bring details about breathlessness, chest discomfort, dizziness or fainting, palpitations, swelling, and any change in activity tolerance. Also mention known heart disease and relevant family history. The next test should answer a particular clinical question.
On a small screen, scroll the table sideways to read all columns.
| Assessment | What it records or shows | How it contributes |
|---|---|---|
| Stethoscope examination | Heart sounds heard at different locations. | Characterizes the murmur and helps decide whether further investigation is needed. |
| Echocardiogram, or echo | Ultrasound images of heart structures and movement; Doppler assesses blood flow. | Helps identify valve abnormalities and their effects on heart function. |
| Electrocardiogram, ECG or EKG | Electrical activity. | Provides information about rhythm and electrical patterns; it is not a picture of the valves. |
| Other tests when indicated | For example, exercise testing or additional imaging. | Answers questions left by the history, examination, and initial tests. |
The NHLBI guide to diagnosing valve disease explains echo and the other tests. Not everyone needs every test in the table. Ask what a proposed test will clarify and how its result could change follow-up or treatment.
Invented example: A clinician hears a murmur during a routine visit, arranges an echo, and later explains that a valve has a mild leak. The useful next information is which valve, how significant the leak is, whether it affects heart function, and when reassessment is due. The word “murmur” alone does not answer those questions.
What digital stethoscopes and AI can add
A digital stethoscope can record heart sounds for review. A phonocardiogram displays sound over time; it is different from an ECG, which records electrical activity. Some systems analyze the recording to flag findings that deserve a clinician's attention.
For a concrete example, the FDA clearance documentation for Eko EFAST (PDF) describes software that assists professionals with heart-sound assessment and, when ECG data are available, certain rhythm findings. Its labeling explicitly places the result within professional evaluation and does not allow it to serve as the sole diagnosis. The allowed patient populations also differ by function.
Read a performance claim in terms of the exact device, software version, population, and task tested. Detecting a possible structural murmur is not the same as identifying every valve disorder or determining whether surgery is needed. Recording quality matters, and false alarms and missed findings remain possible. A consumer phone recording or a general-purpose chatbot should not be treated as equivalent to a validated clinical system.
If AI is used during an appointment, useful questions are: What did it flag? Did the clinician agree? Does it change the need for echo? Where is the recording stored, and who can access it? These questions focus the technology discussion on your care and information.
Leave with a follow-up plan
When valve disease is found, the plan may range from scheduled monitoring to medicines or a procedure, depending on the specific condition. Feeling well does not automatically mean follow-up can stop. Conversely, a murmur does not automatically mean an operation is needed. The NHS overview of valve disease describes symptoms, monitoring, and treatment pathways.
Download a heart-murmur follow-up worksheet (CSV). Use it to record the clinician's explanation and any test or appointment still outstanding. Keep “not yet known” separate from “normal.”
- Has the murmur been classified as innocent, or is its cause still being investigated?
- If the echo shows a problem, what is its exact name and severity?
- Do I need any changes to activity, and for how long?
- When should follow-up occur, and who arranges it?
- Which new symptoms should prompt earlier contact?
Seek emergency help for severe breathing difficulty, sudden concerning chest pain, or chest pain with breathlessness. Call your local emergency number, such as 911 in the United States; do not wait for a scheduled echo. Recurrent breathlessness, worsening exercise tolerance, palpitations, or swelling also deserves medical assessment. Those symptoms can have several causes, so do not assume the murmur explains them.
If your question is about cholesterol or a home lipid meter instead, see how to interpret home cholesterol testing. Cholesterol tests assess a different part of cardiovascular health and cannot determine why a murmur is present.
Related resources
Researched and updated September 6, 2026. General health information, not an individual diagnosis or treatment plan. Sources are linked beside the relevant information.