Heart murmurs are created by turbulent blood flow, particularly the heart valves.
Heart murmurs can be found in new borns and children. The can also develop later in life.
Often, heart murmurs are innocent and don't require treatment.
Many patients will not have symptoms to report.
This is true of innocent murmurs as well as abnormal murmurs.
Abnormal heart murmurs may cause symptoms such as:
- Chest pain
- Heart palpitations
- Heavy sweating with minimal or no exertion
- Shortness of breath
- Bluish skin color or fingertips
On this website, we provide lessons, reference guides and quizzes for auscultating heart murmurs.
This includes gaining an understanding of cardiac rate and rhythm, conditions of the valves and possible anatomical abnormalities such as congenital defects.
Links to our lessons, guides and quizzes are found in the 'Quick Links' box to the left.
The sections below are a listening guide for heart murmurs.
With heart murmurs, the characteristic "lub-DUP" S1 and S2 sounds are changed. Additional sounds or modified S1 & S2 sounds are auscultated.
Timing and Cadence
Systolic murmurs occur between the first heart sound (S1) and the second heart sound (S2).
Diastolic murmurs occur between S2 and S1.
In addition, timing is used to describe when murmurs occur within systole or diastole.
For example, early systolic, midsystolic or late systolic.
See our courses on Systolic and Diastolic Murmurs for more information including audio recordings, waveforms and animations.
Heart murmur duration refers to the portion of systole or diastole that the murmur occupies. Terms used include short and long. Murmurs lasting throughout systole are referred to as holosystolic or pansystolic.
Evaluation of the murmur's pitch should be made by classifying the pitch (frequency) as low, medium or high. The stethoscope's bell can be helpful with low pitched sounds while the diaphragm is used for medium or high pitched sounds.
Some murmurs are described by the sound's shape. Common classifications include crescendo (increasing intensity), decrescendo (decreasing intensity), crescendo-decrescendo (increasing then immediate decreasing intensity). Crescendo-decrescendo is also called diamond shaped. Rectangular, also termed plateau indicates a heart murmur of constant intensity. Our heart sound lessons include waveforms that illustrate these shapes.
Listen for additional aspects of the murmur's sounds. Heart murmurs may have qualities that can be noted as
musical, harsh, blowing, booming, sharp or dull.
Respiration and Patient Position
Respiration or patient position can influence murmur intensity as well as heart sound splitting. These factors will be described within the heart sound lessons. Generally speaking, murmurs increasing with expiration originate with left side (aortic or mitral) valves, while murmurs increasing in intensity with inspiration originate with tricuspid or pulmonary valves.
Within each lesson, the author provides an sketch of the patient's position during auscultation, such as supine, left lateral decubitus, squatting or sitting.