Normal Heart Sound
A normal heart sound showing S1 and S2. No audible murmurs.
Contributor: Thinklabs Medical
Blood Pressure: Korotkoff Sounds 1
Auscultatory blood pressure measurement showing onset of Korotkoff sounds at systolic pressure, and diminishing sounds as diastolic pressure is reached.
Note that last (diastolic) pulse is barely audible but clearly visible.
Contributor: Alice Mayfield, Mechanical & Biomedical Engineering,
Carnegie-Mellon University
Blood Pressure: Korotkoff Sounds 2
Blood pressure sounds with slowly deflating cuff.
Notice that slower deflation provides for more beats and potentially increased accuracy for onset of systole or detection of diastolic end-point.
Contributor: Alice Mayfield, Mechanical & Biomedical Engineering,
Carnegie-Mellon University
Aortic Regurgitation
Murmur best heard with patient sitting forward, Stethoscope in bell mode positioned over the second intercostal space to the right of right of the sternal border, or over the 3rd - 4th intercostal space just to the left of the sternal border. Murmur is enhanced during expiration.
Note that the aortic component of the second heart sound is soft.
The characteristic murmur is an early diastolic murmur. The intensity is loudest at the onset of diastole and becomes softer during diastole - the so-called "decrescendo" murmur.
Contributor: Dr. Darryl A Smith FCP (SA) Cardiology
Aortic Regurgitation, Ejection Systolic Murmur
The stethoscope is positioned towards the left sternoclavicular junction. Note in this recording the ejection systolic murmur early in systole. The aortic regurgitant murmur is less prominent in this position. Patients with aortic valvular disease may have concomitant aortic stenosis and aortic regurgitation, or may have isolated aortic regurgitation.
This patient had isolated aortic regurgitation.
The incompetent valve allows blood to re-enter the left ventricle, which results in an increased volume of blood being ejected during the subsequent beat. The increased volume of blood ejected during systole creates an audible ejection systolic murmur.
Contributor: Dr. Darryl A Smith FCP (SA) Cardiology
Aortic Stenosis
Systolic Murmur. Harsh blowing sound, crescendo / decrescendo during systole, followed by S2. Recording Note: Diaphragm mode recording 0-14 sec. followed by Bell Mode recording 14-29 sec. with increase in S2 due to greater low frequency sensitivity in Bell mode.
Contributor: Division of Cardiology, Emory University School of Medicine
Coarctation of the Aorta
Usually occurs proximal to the origin of the left subclavian artery.
The murmur is best heard with the stethoscope positioned posteriorly in the left suprascapular region using the diaphragm mode. A thrill may be palpable over the left ribs posteriorly due to collateral arteries involving the intercostals arteries.
Contributor: Dr. Darryl A Smith FCP (SA) Cardiology
Congestive Heart Failure (S3)
Noticeable third heart sound (S3) during diastole following S2, producing galloping sound.
S3 is extremely low frequency and requires good headphones with sealed eartips to hear clearly.
Due to low frequency content, set stethoscope to Bell mode.
Contributor: Division of Cardiology, Emory University School of Medicine
The Heart Sound Library is a reference collection curated by the Thinklabs Community, captured on Thinklabs stethoscopes, and recorded on smartphones, mobile devices, and laptops.
Recordings using Thinklabs stethoscopes are used by online medical journals, medical schools, teaching hospitals, electronic medical textbooks, and many research institutions worldwide.
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This online collection is an evolving resource. We welcome contributions from researchers, academics and clinicians. We'd like to hear from you if you have sounds to share, or if you'd like help with your projects.
Hypertrophic Cardiomyopathy
The recording was made with the patient supine. The stethoscope is positioned in the 3rd - 4th intercostal space along the left parasternal border i.e just to the left of the sternum using the diaphragm mode. The stethoscope is over the left ventricular outflow tract, below the level of the aortic valve.
The obstruction is "dynamic", i.e the obstruction becomes progressively more severe as the ventricle contracts. The murmur therefore increases in intensity during systole as the obstruction increases. The murmur may be confused with that of aortic stenosis. Note however that the aortic component of the second heart sound is easily audible, whereas in aortic stenosis the second heart sound is usually soft.
Contributor: Dr. Darryl A Smith FCP (SA) Cardiology
Infective Endocarditis Mitral Regurgitation
Minor Cardiomyopathy
S3 immediately following S2, producing a "gallop."
Third heart sound has low frequency energy and is best heard in Bell mode.
Contributor: Division of Cardiology, Emory University School of Medicine
Mitral Regurgitation
Holosystolic murmur, recorded at the Apex.
High frequency murmur is clearly visible on the phonocardiogram.
S2 is somewhat diminished at the Apex.
Contributor: Division of Cardiology, Emory University School of Medicine
Mitral Regurgitation Tricuspid Regurgitation (MR TR)
Systolic murmur (holosystolic)
Contributor: Division of Cardiology, Emory University School of Medicine
Pericarditis
A pericardial friction rub is a rough scraping sound described as "leather rubbing against leather" that may be heard in systole and/or diastole. It is more pronounced if the patient is supine, and diminishes as the patient sits forward.
Contributor: Terry Bauch MD, FACC, FACP
Mitral Stenosis
The typical auscultatory features of mitral stenosis are a loud S1, early opening snap (OS) of the mitral valve soon after S2, a low-pitched mid-diastolic murmur (MDM) or "rumble" and pre-systolic accentuation (PSA). The murmur is best heard with the patient lying in the left lateral position, using the stethoscope in the Bell mode.
Contributor: Dr. Darryl A Smith FCP (SA) Cardiology
Prosthetic Mitral Valve
Prosthetic Valve Aortic Valve Mitral Regurgitation
Prosthetic Mitral Valve Systolic Murmur Mid-Diastolic Murmur
Prosthetic Valve Systolic Murmur
S2 Split
Breath sounds clearly audible, should not be confused with murmur on phonocardiogram.
Contributor: Division of Cardiology, Emory University School of Medicine
Ventricular Septal Defect
Congenital Muscular Ventricular Septal Defect in an adult. Low frequency systolic murmur. The murmur is characteristically loudest in the 4th intercostal space along the left parasternal border.
Contributor: Terry Bauch MD, FACC, FACP
S4 Gallop
S4 occurs just prior to S1, clearly audible as 2 sounds - S4 quickly followed by S1. Fourth heart sound may be present in patients with hypertension or
following an anterior myocardial infarct.
Contributor: Division of Cardiology, Emory University School of Medicine
