Heart Sounds

Auscultation of the heart is a useful skill for respiratory care. Our website provides introductory heart sounds training, including our "Essential Heart Sounds" course, which is outlined below.

heart sounds image

Heart Sounds Lessons

These lesson provide an excellent way to learn heart sounds commonly observed in primary care and respiratory care. Each lesson includes an audio recording, a written description of the heart sound, a presentation of the heart sound's waveform (a phonocardiogram) and a short video illustrating the sources of the heart sound.

For additional auscultation courses, we recommend the website EasyAuscultation.com.

Essential Heart Sounds
This module, 'Essential Heart Sounds', is designed to provide auscultation instruction with practice exercises. The most important heart sounds found in family practice and internal medicine are covered. Each lesson consists of multiple pages: 1) text description with audio recording; 2)a visualization page with waveform; 3) animation of the heart valves and 4) a practice page. Use the tabs which appear below each lesson's title.
Lesson List

Where to Auscultate

The illustration provides a reference to auscultation positions which are used throughout our courses.

heart murmur sounds auscultation location areas
aortic valve auscultation location area Aortic Valve Area Second right intercostal space (ICS), right sternal border
pulmonic valve auscultation location area Pulmonic Valve Area Second left intercostal space (ICS), left sternal border
Erb's Point  auscultation location area Erb's Point Third left ICS, left sternal border
tricuspid valve auscultation location area Tricuspid Valve Area Fourth left ICS, left sternal border
mitral valve auscultation location area Mitral Valve Area Fifth ICS, left mid-clavicular line

Heart Murmur Timing

When listening to heart murmurs, note the timing within a cardiac cycle. Systolic murmurs are heard between S1 (first heart sound) and S2 (second heart sound). Diastolic murmurs occur between S2 and S1. Murmurs can occur within systole or diastole and terms such as early systolic, mid-systolic or late systolic are used in our lessons.


The duration of a heart murmur should be noted. A murmur that lasts the entire systolic interval is called a holosystolic murmur.


Listening to the pitch (frequency) of the heart sound, noting if the pitch is low, medium or high. The stethoscope's bell is useful for low pitched sounds while the diaphragm is used for medium and high frequencies.

Heart Murmur Shape

Murmurs can vary in sound intensity during a single heart beat. Murmurs that increase in intensity are crescendo murmurs while those murmurs with decreasing sound levels are called decrescendo murmurs. Crescendo-decrescendo murmurs have sound levels that increase then immediately decrease in intensity. Rectangular heart murmurs have a uniform sound intensity.

crescendo-decresendo heart murmur phonocardiogram decrescendo heart murmur