Systolic murmur: Types and characteristics

Systolic murmur: Types and characteristics

What do we mean by systolic murmur?

A systolic murmur can be defined as heart sound where there is prolonged vibration caused due to the disturbance in the flow of the blood which manifests turbulence in the blood of maximum intensity generally corresponds to the site of turbulence. It is the abnormal heart sound which occurs during contraction of the cardiac muscle which occurs between the first heart sound (S1) and the second heart sound (S3).

Where the systolic sound can be auscultated?

The systolic sound can be auscultated in the following given areas :

  1. Aortic area: systolic murmur can be heard best at 2nd intercostal space and the left upper sternal border.
  2. Pulmonic area: This area also lies at the 2nd intercostal space and right upper sternal border.
  3. Tricuspid area: This area lies at the 5th intercostal space and the left midclavicular line.
  4. Erb’s point: murmur can be best heard at the 3rd intercostal space and left lower sternal border.
  5. Mitral or apical area: This area lies just near 4th intercostal space and lower sternal border.

How does systolic murmur originate?

Systolic murmur is produced when the normal blood flow in the vessels increases form normal to the abnormal orifice. It is also produced when blood gets backflow through the incompetent valves or vessels get dilated.

What is the mechanism of systolic murmur?

You previously came to know about how systolic murmur originates. So when systolic murmur originates due to the turbulent flow of blood, it arises when Reynold’s number reaches >2000 i.e velocity of the blood flow gets high, the diameter of the vessel is small, and the kinetic viscosity of blood is lesser.

READ – Do cardiac workouts work for heart valve diseases?

Basic characteristics

The basic characteristics shown by the murmur are as follows:

  1. Intensity: it is the loudness of the sound produced due to the turbulent flow of blood in the vessel.
  2. Pitch: It is the frequency of the abnormal sound of heart which mainly depends upon the velocity of the blood vessels.
  3. Timing: systolic murmur starts with or after first heart sound (S1) and ends with or before second heart sound (S2). It basically depends upon the sound of the heart.

Do you know what is cardiac tamponade?


This article will help you to find some signs of the systolic murmur which are like getting the skins of lips and fingers getting blue, pain in the thoracic region especially near the chest, difficulty in the Breathing while doing any heavy work such as “ gyms, exercises” etc.

Read about Myocardial infarction

What are the different types of systolic murmur?

There are different forms of systolic murmur. The various forms of systolic murmur are discussed below:

Mid systolic murmur: It is caused due to the flow of blood through the semilunar valve. It is heard best in the aortic stenosis and with the rise and the fall changes the intensity of heart sound.

Late systolic murmur: It causes the mitral valve prolapse. It is best auscultated in the area of the heart’s apex. It can also lead to myocardial infarction.

Holosystolic murmur: In this murmur, first heart sound( S1) is heard before second heart sound (S2). It is high pitched abnormal sound due to the mitral prolapse or Tricuspid regurgitation. It best listens at the cardiac apex.

Some of the terms related to the murmur and its effects:

Aortic stenosis: It occurs due to the narrowing of the aortic valve of the heart. The causes of aortic stenosis are Rheumatic Fever. It gets more severe aa time passes. The survival rate is 50% after the replacement of valve surgery.

Pulmonic stenosis: It occurs due to the narrowing of the pulmonic valve. It restricts the blood flow in the adequate amount to pulmonary vessels from the ventricle of the heart. The mild symptoms of the pulmonary stenosis are cyanosis skin, rapid and irregular heartbeat, tiredness etc.

Mitral regurgitation: It is the flow of the blood in the reverse direction from the left ventricle to the left auricle due to the disturbance in the mitral valve. Some of the pathological aetiology of the mitral regurgitation are ischemic heart disease, Coronary heart disease etc.

Some of the serious clinical causes due to the systolic murmur are as follows :

Coronary artery disease: It is the blockage in the coronary artery. Due to the blockage in the Coronary arteries, it restricts or limits the blood flow to the cardiac muscle. It may lead to systolic heart failure.

High Blood pressure: Due to the disturbed blood flow to the various orifices of the heart. It elevates the internal pressure in the arteries. It may lead to cardiac arrest.

Arrhythmia: Due to the disruptive and limited blood flow to the vessel and cardiac muscle, the heart doesn’t beat in the proper regular heart rhythms.


Systolic murmur is the abnormal heart sound. It can be best listened at the 2nd intercostal space region and at the left sternal border with the help of stethoscope most frequently.

This abnormal condition of the heart sound may lead to the various serious clinical conditions related to the heart. You must emphasize the healthy heart to live a healthy life. You must take care of the heart and be aware of the problems related to the heart

Related article – Heart failure guidelines

Mehedi Hasan

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