Heartsounds

Heartsounds

Heartsounds are the noises generated by the beating heart and the resultant flow of blood through it. These sounds are typically heard using a stethoscope during auscultation. The study of heartsounds is an important aspect of cardiology and can provide valuable information about the condition of the heart.

Normal Heartsounds

The normal heartsounds are often described as "lub-dub" and are known as the first heart sound (S1) and the second heart sound (S2).

First Heart Sound (S1)

The first heart sound, S1, is associated with the closure of the atrioventricular valves, which include the mitral valve and the tricuspid valve. This sound marks the beginning of ventricular systole, the phase of the cardiac cycle when the ventricles contract.

Second Heart Sound (S2)

The second heart sound, S2, is associated with the closure of the semilunar valves, which include the aortic valve and the pulmonary valve. This sound marks the end of ventricular systole and the beginning of ventricular diastole, the phase when the ventricles relax and fill with blood.

Abnormal Heartsounds

Abnormal heartsounds can indicate various cardiac conditions and are often referred to as heart murmurs or extra heart sounds.

Heart Murmurs

Heart murmurs are sounds during the heartbeat cycle, such as whooshing or swishing, made by turbulent blood in or near the heart. They can be classified as either systolic or diastolic murmurs, depending on when they occur in the cardiac cycle.

Third Heart Sound (S3)

The third heart sound, S3, is a low-frequency sound that occurs just after S2. It is often associated with increased volume of blood within the ventricle and can be a normal finding in children and young adults. However, in older adults, it may indicate heart failure or other cardiac conditions.

Fourth Heart Sound (S4)

The fourth heart sound, S4, occurs just before S1 and is associated with atrial contraction. It is often heard in conditions where the ventricle is stiff, such as in hypertensive heart disease or aortic stenosis.

Clinical Significance

The analysis of heartsounds is a crucial part of the physical examination in medicine. It can help in diagnosing various heart conditions, such as valvular heart disease, congestive heart failure, and congenital heart defects.

See Also

• Auscultation
• Cardiac cycle
• Heart murmur

Cardiovascular disease A-Z

Most common cardiac diseases

• Cardiac arrhythmia‎
• Cardiogenetic disorders‎
• Cardiomegaly‎
• Cardiomyopathy‎
• Cardiopulmonary resuscitation‎
• Chronic rheumatic heart diseases‎
• Congenital heart defects‎
• Heart neoplasia‎
• Ischemic heart diseases‎
• Pericardial disorders
• Syndromes affecting the heart‎
• Valvular heart disease‎

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

A

• Accelerated idioventricular rhythm
• Acute decompensated heart failure
• Arteriosclerotic heart disease
• Athletic heart syndrome
• Atrial flutter
• Atrioventricular fistula
• Cardiovascular disease in Australia
• Autoimmune heart disease

B

• Brown atrophy of the heart

C

• Ebb Cade
• Cardiac allograft vasculopathy
• Cardiac amyloidosis
• Cardiac asthma
• Cardiac tamponade
• Cardiogenic shock
• Cardiogeriatrics
• Cardiorenal syndrome
• Cardiotoxicity
• Carditis
• Coronary artery aneurysm
• Coronary artery anomaly
• Coronary artery disease
• Spontaneous coronary artery dissection
• Coronary artery ectasia
• Coronary occlusion
• Coronary steal
• Coronary thrombosis
• Coronary vasospasm
• Cœur en sabot
• Coxsackievirus-induced cardiomyopathy

D

• Duke Treadmill Score
• Duroziez's disease

E

• Eisenmenger's syndrome
• Embryocardia
• Endocardial fibroelastosis
• Eosinophilic myocarditis

H

• Heart attack
• Heart failure
• Heart failure with preserved ejection fraction
• Heart to Heart (1949 film)
• High-output heart failure
• Hyperdynamic precordium

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

I

• Idiopathic giant-cell myocarditis
• Interventricular dyssynchrony
• Intraventricular dyssynchrony
• Isolated atrial amyloidosis

K

• Keshan disease

L

• Loeffler endocarditis

M

• Mydicar
• Myocardial bridge
• Myocardial disarray
• Myocardial rupture
• Myocardial scarring
• Myocardial stunning
• Myocarditis

N

• Nonbacterial thrombotic endocarditis

O

• OLR1
• Ostial disease

P

• Papillary fibroelastoma
• Pathophysiology of heart failure
• Postpericardiotomy syndrome
• Pulmonary vein stenosis

R

• Right axis deviation
• Roemheld syndrome

S

• Saturated fat and cardiovascular disease
• SCAR-Fc
• Shone's syndrome
• Strain pattern
• Subacute bacterial endocarditis
• Sudden cardiac death of athletes

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

T

• Traumatic cardiac arrest

V

• Ventricular aneurysm
• Vibroacoustic disease
• Viral cardiomyopathy

W

• Waon therapy