Heart Sounds

Overview

Heart sounds

• Heart sounds are produced by:
  • Valve opening and closure
  • Movement of blood in the heart
• The more turbulent the flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure, the more audible the created vibrations.
• On auscultation, 2 heart sounds heard from a normal heart are reflective of the cardiac cycle Cardiac cycle The cardiac cycle describes a complete contraction and relaxation of all 4 chambers of the heart during a standard heartbeat. The cardiac cycle includes 7 phases, which together describe the cycle of ventricular filling, isovolumetric contraction, ventricular ejection, and isovolumetric relaxation. Cardiac Cycle.
  • The cardiac cycle Cardiac cycle The cardiac cycle describes a complete contraction and relaxation of all 4 chambers of the heart during a standard heartbeat. The cardiac cycle includes 7 phases, which together describe the cycle of ventricular filling, isovolumetric contraction, ventricular ejection, and isovolumetric relaxation. Cardiac Cycle is a sequence of pressure changes in the heart, resulting in:
    • Systole Systole Period of contraction of the heart, especially of the heart ventricles. Cardiac Cycle (ventricular contraction and ejection of blood) and
    • Diastole Diastole Post-systolic relaxation of the heart, especially the heart ventricles. Cardiac Cycle (ventricular relaxation and filling)
  • S1 and S2 mark the beginning and end, respectively, of the cardiac cycle Cardiac cycle The cardiac cycle describes a complete contraction and relaxation of all 4 chambers of the heart during a standard heartbeat. The cardiac cycle includes 7 phases, which together describe the cycle of ventricular filling, isovolumetric contraction, ventricular ejection, and isovolumetric relaxation. Cardiac Cycle phases: systole Systole Period of contraction of the heart, especially of the heart ventricles. Cardiac Cycle and diastole Diastole Post-systolic relaxation of the heart, especially the heart ventricles. Cardiac Cycle; they are high-frequency sounds.
  • Colloquially referred to as the “lub-dub” sound of the heart
• S3 and S4 are low-frequency sounds which may be heard in various conditions.

S1 and S2

S1

• Closure of the atrioventricular (AV) valves
• Mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy (M1) closes before the tricuspid valve Tricuspid valve The valve consisting of three cusps situated between the right atrium and right ventricle of the heart. Heart: Anatomy (T1).
• Indicates the start of systole Systole Period of contraction of the heart, especially of the heart ventricles. Cardiac Cycle
• Coincides with the QRS complex QRS complex Electrocardiogram (ECG) and isovolumetric contraction Isovolumetric contraction Cardiac Cycle (beginning of systole Systole Period of contraction of the heart, especially of the heart ventricles. Cardiac Cycle)
• Loudest over the mitral area (cardiac apex)

S2

• Closure of the semilunar valves (pulmonary and aortic)
• Indicates the start of diastole Diastole Post-systolic relaxation of the heart, especially the heart ventricles. Cardiac Cycle
• Occurs just after the T-wave and coincides with isovolumetric relaxation Isovolumetric relaxation Cardiac Cycle (beginning of diastole Diastole Post-systolic relaxation of the heart, especially the heart ventricles. Cardiac Cycle)
• The aortic valve Aortic valve The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle. Heart: Anatomy (A2 component of S2) closes before the pulmonic valve (P2 component of S2).
• Loudest at left upper sternal border

Audio:

Normal S1 and S2: In this audio clip, normal S1 and S2 heart sounds can be heard. S1 corresponds to the closure of the AV valves, marking the beginning of systole Systole Period of contraction of the heart, especially of the heart ventricles. Cardiac Cycle. S2 corresponds to the closure of the semilunar valves, marking the beginning of diastole Diastole Post-systolic relaxation of the heart, especially the heart ventricles. Cardiac Cycle.

S3 and S4

S3 and S4 sounds are heard in certain clinical situations and are produced by turbulent blood entering the ventricle at different points during diastole. S3 and S4 are the so-called “extra heart sounds.” They are low-frequency sounds.

S3

• Rapid filling phase of ventricular diastole Ventricular diastole Cardiac Cycle
• ↑ Left ventricular filling Ventricular filling Cardiac Cycle pressure → ↑ cardiac output Cardiac output The volume of blood passing through the heart per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with stroke volume (volume per beat). Cardiac Mechanics
• Best heard at the apex (left lateral decubitus position)
• Can be normal in children, pregnant women, and athletes
• Associated pathologic conditions:
  • Dilated cardiomyopathy Dilated Cardiomyopathy Dilated cardiomyopathy (DCM) is the most common type of non-ischemic cardiomyopathy and a common cause of heart failure (HF). The cause may be idiopathic, familial, or secondary to a variety of underlying conditions. The disease is characterized by the enlargement of 1 or both ventricles and reduced systolic function. Dilated Cardiomyopathy
  • Congestive heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR)
  • Chronic mitral regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD) ( MR MR Calculated as the ratio of the total number of people who die due to all causes over a specific time period to the total number of people in the selected population. Measures of Health Status)
  • Chronic aortic regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD) ( AR AR Aortic regurgitation (AR) is a cardiac condition characterized by the backflow of blood from the aorta to the left ventricle during diastole. Aortic regurgitation is associated with an abnormal aortic valve and/or aortic root stemming from multiple causes, commonly rheumatic heart disease as well as congenital and degenerative valvular disorders. Aortic Regurgitation)
  • Thyrotoxicosis Thyrotoxicosis A hypermetabolic syndrome caused by excess thyroid hormones which may come from endogenous or exogenous sources. The endogenous source of hormone may be thyroid hyperplasia; thyroid neoplasms; or hormone-producing extrathyroidal tissue. Thyrotoxicosis is characterized by nervousness; tachycardia; fatigue; weight loss; heat intolerance; and excessive sweating. Thyrotoxicosis and Hyperthyroidism

Audio:

S3: In this audio clip, the S3 gallop S3 gallop Heart Failure can be heard (left decubitus, heard with the bell of the stethoscope). S3 occurs after S2 during the rapid filling phase of ventricular diastole Ventricular diastole Cardiac Cycle.

S4

• Atrial contraction or “kick” during ventricular diastole Ventricular diastole Cardiac Cycle
• Due to ventricular noncompliance Noncompliance Clinician–Patient Relationship or stiffness
• May be auscultated in older adults due to loss of ventricular compliance Compliance Distensibility measure of a chamber such as the lungs (lung compliance) or bladder. Compliance is expressed as a change in volume per unit change in pressure. Veins: Histology with age
• Best heard at the apex (left lateral decubitus position)
• Associated conditions:
  • Hypertrophic cardiomyopathy Hypertrophic Cardiomyopathy Hypertrophic cardiomyopathy (HCM) is the most commonly inherited cardiomyopathy, which is characterized by an asymmetric increase in thickness (hypertrophy) of the left ventricular wall, diastolic dysfunction, and often left ventricular outflow tract obstruction. Hypertrophic Cardiomyopathy
  • AS

Audio:

S4 gallop: In this audio clip, the S4 gallop can be heard (left decubitus, heard with the bell of the stethoscope). S4 occurs before S1 during the atrial filling phase. S4 is heard in conditions where there is stiffness or low compliance Compliance Distensibility measure of a chamber such as the lungs (lung compliance) or bladder. Compliance is expressed as a change in volume per unit change in pressure. Veins: Histology in the ventricle.

Respiratory Variation

An increase in right ventricular (RV) volume (occurring with inspiration Inspiration Ventilation: Mechanics of Breathing) affects the right side of the heart and is heard as splitting Splitting Defense Mechanisms of S2 (A2 and P2).

Physiologic splitting Splitting Defense Mechanisms

• Associated condition: inspiration Inspiration Ventilation: Mechanics of Breathing
• In inspiration Inspiration Ventilation: Mechanics of Breathing:
  • ↑ Venous return, ↑ RV filling and volume 
  • Delays closure of pulmonic valve → delays P2

Widened or persistent splitting Splitting Defense Mechanisms

• Description:
  • Delayed RV emptying → delayed pulmonic sound (exaggeration of normal splitting Splitting Defense Mechanisms)
  • Varies with inspiration Inspiration Ventilation: Mechanics of Breathing
• Associated conditions:
  • Pulmonic stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) ( PS PS Invasive Mechanical Ventilation)
  • Right bundle branch block Right bundle branch block Bundle Branch and Fascicular Blocks

Audio:

Persistent S2 splitting Splitting Defense Mechanisms: heard in right bundle branch block Right bundle branch block Bundle Branch and Fascicular Blocks (listening with the diaphragm Diaphragm The diaphragm is a large, dome-shaped muscle that separates the thoracic cavity from the abdominal cavity. The diaphragm consists of muscle fibers and a large central tendon, which is divided into right and left parts. As the primary muscle of inspiration, the diaphragm contributes 75% of the total inspiratory muscle force. Diaphragm: Anatomy of the stethoscope)

Fixed splitting Splitting Defense Mechanisms

• Description:
  • ↑ Right atrial (RA) and RV volume (due to left-to-right shunt)
  • ↑ Blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure through the pulmonic valve
  • Delays closure of the pulmonic valve
• Associated condition: atrial septal defect Atrial Septal Defect Atrial septal defects (ASDs) are benign acyanotic congenital heart defects characterized by an opening in the interatrial septum that causes blood to flow from the left atrium (LA) to the right atrium (RA) (left-to-right shunt). Atrial Septal Defect (ASD) ( ASD ASD Autism spectrum disorder (ASD) is a neurodevelopmental disorder marked by poor social skills, restricted interests/social interactions, and repetitive/stereotyped behaviors. The condition is termed a “spectrum” because of the wide variability in the severity of symptoms exhibited. Autism Spectrum Disorder)

Paradoxical splitting Splitting Defense Mechanisms

• Description:
  • Delayed aortic valve Aortic valve The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle. Heart: Anatomy closure
  • Pulmonic valve closure (P2) occurs before delayed aortic valve Aortic valve The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle. Heart: Anatomy closure (A2).
• Associated conditions:
  • Delayed aortic valve Aortic valve The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle. Heart: Anatomy closure due to obstruction:
    • Aortic stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) (AS)
    • Hypertrophic obstructive cardiomyopathy Cardiomyopathy Cardiomyopathy refers to a group of myocardial diseases associated with structural changes of the heart muscles (myocardium) and impaired systolic and/or diastolic function in the absence of other heart disorders (coronary artery disease, hypertension, valvular disease, and congenital heart disease). Cardiomyopathy: Overview and Types (HOCM)
  • Delayed aortic valve Aortic valve The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle. Heart: Anatomy closure due to conduction disease: left bundle branch block Left bundle branch block Bundle Branch and Fascicular Blocks

Clicks and Snaps

Clicks

• A high-pitched sound occurring at the point of maximal opening of the valves
• Occurs after S1 (systolic)
• Can be ejection or nonejection clicks:
  • Ejection clicks:
    • Aortic or pulmonary in etiology
    • Heard in early systole Systole Period of contraction of the heart, especially of the heart ventricles. Cardiac Cycle, indicating the rapid opening of a semilunar valve or distention of the aorta Aorta The main trunk of the systemic arteries. Mediastinum and Great Vessels: Anatomy during the beginning of ventricular ejection Ventricular ejection Cardiac Cycle
  • Nonejection click:
    • Mitral or tricuspid in etiology
    • Usually mid-to-late systolic: swelling Swelling Inflammation out and sudden stop of the leaflets of a prolapsed mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy

Audio:

Mid-systolic click (MSC): This audio clip is an example of an MSC heard in mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy prolapse. An MSC is a crisp sound occurring between S1 and S2 (no murmur follows).

Snap

• A high-frequency diastolic sound made by the opening of a stenotic mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy (most common)
• Leaflets swell out into the ventricle and suddenly stop, producing a mid-to-high–frequency sound.

Audio:

Opening snap Opening snap Mitral Stenosis: A mitral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) murmur can be heard in this audio clip. The low-pitched, rumbling murmur starts after the opening snap Opening snap Mitral Stenosis of the mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy (after S2) and finishes with a short crescendo up to S1.

Murmurs

Heart murmurs

• Murmurs are audible vibrations that can be produced by the following:
  • Accelerated blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure (e.g., increased preload Preload Cardiac Mechanics)
  • Flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure through a narrow opening (e.g., valvular stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS))
  • Backward flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure through an incompetent valve (e.g., valvular regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD))
• Not all murmurs indicate structural heart disease.
• Determine characteristics by:
  • Timing ( cardiac cycle Cardiac cycle The cardiac cycle describes a complete contraction and relaxation of all 4 chambers of the heart during a standard heartbeat. The cardiac cycle includes 7 phases, which together describe the cycle of ventricular filling, isovolumetric contraction, ventricular ejection, and isovolumetric relaxation. Cardiac Cycle)
  • Intensity
  • Pattern or configuration
  • Pitch and quality Quality Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps. Quality Measurement and Improvement
  • Location or auscultation area
  • Maneuvers, position, and exercise

Classification according to cardiac cycle Cardiac cycle The cardiac cycle describes a complete contraction and relaxation of all 4 chambers of the heart during a standard heartbeat. The cardiac cycle includes 7 phases, which together describe the cycle of ventricular filling, isovolumetric contraction, ventricular ejection, and isovolumetric relaxation. Cardiac Cycle

• Systolic (occurs at or after S1 and ends before or at S2)
  • Early systolic: heard in acute mitral or tricuspid regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD) (TR)
  • Midsystolic: aortic or pulmonary stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS)
  • Holosystolic:
    • Mitral or TR
    • Ventricular septal defect Ventricular Septal Defect Tetralogy of Fallot (VSD)
  • Late systolic: mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy prolapse
• Diastolic (occurs at or after S2 and ends before or at S1)
  • Early diastolic: aortic or pulmonary regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD)
  • Mid diastolic: mitral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS), tricuspid stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) (TS)
  • Late diastolic (or presystolic):
    • Moderate-to-severe AR AR Aortic regurgitation (AR) is a cardiac condition characterized by the backflow of blood from the aorta to the left ventricle during diastole. Aortic regurgitation is associated with an abnormal aortic valve and/or aortic root stemming from multiple causes, commonly rheumatic heart disease as well as congenital and degenerative valvular disorders. Aortic Regurgitation ( Austin Flint murmur Austin Flint murmur Aortic Regurgitation)
    • Mitral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS)
• Continuous (not confined to either systole Systole Period of contraction of the heart, especially of the heart ventricles. Cardiac Cycle or diastole Diastole Post-systolic relaxation of the heart, especially the heart ventricles. Cardiac Cycle):
  • Patent ductus arteriosus Ductus arteriosus A fetal blood vessel connecting the pulmonary artery with the descending aorta. Patent Ductus Arteriosus (PDA) murmur
  • Arteriovenous fistulas

Audio:

Early diastolic murmur: Aortic regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD), a high-pitched decrescendo murmur, can be heard in this audio clip.

Audio:

Holosystolic murmur Holosystolic Murmur Tricuspid Valve Atresia (TVA): This audio clip presents an example of a holosystolic murmur Holosystolic Murmur Tricuspid Valve Atresia (TVA) from MR MR Calculated as the ratio of the total number of people who die due to all causes over a specific time period to the total number of people in the selected population. Measures of Health Status. The murmur results in a high-pitched “blowing” sound through the entirety of the systole Systole Period of contraction of the heart, especially of the heart ventricles. Cardiac Cycle.

Classification according to intensity

Using the Levine system, murmurs can be graded on a scale Scale Dermatologic Examination from I to VI, which reflects the intensity of the murmur. 

• I: very soft, may only be heard by experienced cardiologists
• II: faint but readily audible
• III: readily audible, louder than grade 2, no thrill
• IV: loud and accompanied by a palpable thrill
• V: loud enough to be heard with a stethoscope lightly touching the chest
• VI: loud enough to be heard with a stethoscope off the chest

Classification according to pattern

• Crescendo-decrescendo murmur:
  • Ascending then descending systolic ejection murmur
  • Diamond shaped
  • Example: AS
• Crescendo:
  • Ascending intensity from faint to loud
  • Example: can be heard in mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy prolapse
• Decrescendo:
  • Descending intensity from loud to faint
  • Example: AR AR Aortic regurgitation (AR) is a cardiac condition characterized by the backflow of blood from the aorta to the left ventricle during diastole. Aortic regurgitation is associated with an abnormal aortic valve and/or aortic root stemming from multiple causes, commonly rheumatic heart disease as well as congenital and degenerative valvular disorders. Aortic Regurgitation
• Uniform/ plateau Plateau Cardiac Physiology: mitral/TR murmur

Audio:

Crescendo-decrescendo murmur: In this audio clip, the sound of severe AS, a harsh, crescendo-decrescendo murmur occurring between S1 and S2, can be heard. The S2 heart sound is inaudible due to the severity of AS.

Classification according to pitch and quality Quality Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps. Quality Measurement and Improvement

• Pitch:
  • Frequency of the murmur
  • High pitch:
    • TR
    • MR MR Calculated as the ratio of the total number of people who die due to all causes over a specific time period to the total number of people in the selected population. Measures of Health Status
    • AR AR Aortic regurgitation (AR) is a cardiac condition characterized by the backflow of blood from the aorta to the left ventricle during diastole. Aortic regurgitation is associated with an abnormal aortic valve and/or aortic root stemming from multiple causes, commonly rheumatic heart disease as well as congenital and degenerative valvular disorders. Aortic Regurgitation
  • Low pitch: mitral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS)
• Quality Quality Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps. Quality Measurement and Improvement: can be blowing, harsh, rumbling, scratchy, vibratory, squeaky, or musical

Auscultation areas

The 5 areas of auscultation can be recalled using the mnemonic, “All People Enjoy Time Magazine.”

1. Aortic area: right 2nd intercostal space adjacent to the sternum Sternum A long, narrow, and flat bone commonly known as breastbone occurring in the midsection of the anterior thoracic segment or chest region, which stabilizes the rib cage and serves as the point of origin for several muscles that move the arms, head, and neck. Chest Wall: Anatomy
   • AS
   • Aortic valve Aortic valve The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle. Heart: Anatomy sclerosis Sclerosis A pathological process consisting of hardening or fibrosis of an anatomical structure, often a vessel or a nerve. Wilms Tumor
   • Systolic flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure murmurs
2. Pulmonic area: left 2nd intercostal space adjacent to the sternum Sternum A long, narrow, and flat bone commonly known as breastbone occurring in the midsection of the anterior thoracic segment or chest region, which stabilizes the rib cage and serves as the point of origin for several muscles that move the arms, head, and neck. Chest Wall: Anatomy
   • PS PS Invasive Mechanical Ventilation
   • Systolic flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure murmurs
3. E rb RB Chlamydia’s (auscultation) point (left sternal border): left 3rd intercostal space
   • Systolic murmurs: HOCM
   • Diastolic murmurs:
     • AR AR Aortic regurgitation (AR) is a cardiac condition characterized by the backflow of blood from the aorta to the left ventricle during diastole. Aortic regurgitation is associated with an abnormal aortic valve and/or aortic root stemming from multiple causes, commonly rheumatic heart disease as well as congenital and degenerative valvular disorders. Aortic Regurgitation
     • Pulmonic regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD) (PR)
4. Tricuspid area: left 4th–5th intercostal space adjacent to the sternum Sternum A long, narrow, and flat bone commonly known as breastbone occurring in the midsection of the anterior thoracic segment or chest region, which stabilizes the rib cage and serves as the point of origin for several muscles that move the arms, head, and neck. Chest Wall: Anatomy
   • Systolic murmurs:
     • TR
     • VSD
   • Diastolic murmurs:
     • TS
     • ASD ASD Autism spectrum disorder (ASD) is a neurodevelopmental disorder marked by poor social skills, restricted interests/social interactions, and repetitive/stereotyped behaviors. The condition is termed a “spectrum” because of the wide variability in the severity of symptoms exhibited. Autism Spectrum Disorder
5. Mitral area (apex): left 4th intercostal space, midclavicular line
   • Systolic murmurs:
     • MR MR Calculated as the ratio of the total number of people who die due to all causes over a specific time period to the total number of people in the selected population. Measures of Health Status (holosystolic)
     • Mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy prolapse
   • Diastolic murmurs: mitral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) ( MS MS Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease that leads to demyelination of the nerves in the CNS. Young women are more predominantly affected by this most common demyelinating condition. Multiple Sclerosis)

Dynamic Auscultation

Cardiac physiology Cardiac Physiology A complex system of coordinated electrical circuitry within the heart governs cardiac muscle activity. The heart generates its own electrical impulses within its pacemaker cells. The signal then travels through specialized myocytes, which act as electrical wiring, distributing the signal throughout the heart. Cardiac Physiology and maneuvers

• Preload Preload Cardiac Mechanics:
  • Stretching of cardiac muscles prior to contraction ( ventricular filling Ventricular filling Cardiac Cycle)
  • ↑ Preload Preload Cardiac Mechanics: increase in venous return into the right ventricle and decrease in venous return to the left ventricle:
    • Deep inspiration Inspiration Ventilation: Mechanics of Breathing
    • Supine position
    • Squatting (seen in tetralogy of Fallot Tetralogy of Fallot Tetralogy of Fallot is the most common cyanotic congenital heart disease. The disease is the confluence of 4 pathologic cardiac features: overriding aorta, ventricular septal defect, right ventricular outflow obstruction, and right ventricular hypertrophy. Tetralogy of Fallot)
    • Passive leg Leg The lower leg, or just “leg” in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia. Leg: Anatomy raise (increased venous return due to gravity)
  • ↓ Preload Preload Cardiac Mechanics: decrease in venous return → ↓ LV volume
    • Valsalva maneuver Valsalva maneuver Forced expiratory effort against a closed glottis. Rectal Prolapse (straining phase)
    • Abrupt standing
• Afterload Afterload Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta. Cardiac Mechanics:
  • Effective pressure against which the heart ejects blood during ventricular contraction
  • ↑ Afterload Afterload Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta. Cardiac Mechanics: handgrip

Effects on the intensity of heart murmurs

• Respiration Respiration The act of breathing with the lungs, consisting of inhalation, or the taking into the lungs of the ambient air, and of exhalation, or the expelling of the modified air which contains more carbon dioxide than the air taken in. Nose Anatomy (External & Internal) (↑ preload Preload Cardiac Mechanics):
  • Inspiration Inspiration Ventilation: Mechanics of Breathing generally increases right-sided murmurs due to increased preload Preload Cardiac Mechanics (on the right).
  • Inspiration Inspiration Ventilation: Mechanics of Breathing generally decreases left-sided murmurs, but expiration Expiration Ventilation: Mechanics of Breathing increases left-sided murmurs.
• While standing and with the Valsalva maneuver Valsalva maneuver Forced expiratory effort against a closed glottis. Rectal Prolapse (↓ preload Preload Cardiac Mechanics), most murmurs decrease, EXCEPT the following:
  • HOCM (becomes louder)
  • Mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy prolapse (becomes longer and louder)
• While squatting and with passive leg Leg The lower leg, or just “leg” in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia. Leg: Anatomy raise (↑ preload Preload Cardiac Mechanics), most murmurs become louder, EXCEPT:
  • HOCM (becomes softer)
  • Mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy prolapse (becomes shorter, except in severe MR MR Calculated as the ratio of the total number of people who die due to all causes over a specific time period to the total number of people in the selected population. Measures of Health Status)
• With isotonic Isotonic Solutions having the same osmotic pressure as blood serum, or another solution with which they are compared. Renal Sodium and Water Regulation and isometric (sustained handgrip) exercise (↑ afterload Afterload Afterload is the resistance in the aorta that prevents blood from leaving the heart. Afterload represents the pressure the LV needs to overcome to eject blood into the aorta. Cardiac Mechanics), most murmurs increase, EXCEPT:
  • HOCM (decreases in intensity)
  • AS (decreases in intensity, helping to differentiate AS from MR MR Calculated as the ratio of the total number of people who die due to all causes over a specific time period to the total number of people in the selected population. Measures of Health Status)

Mnemonics

• rIght-sided murmurs: increase with Inspiration
• lEft-sided murmurs: increase with Expiration

Specific Murmurs

The table below lists cardiac abnormalities with their corresponding murmurs.

Mnemonics for valvular murmurs

• Systolic murmurs: “MR. PV TR-APS”
  • MR MR Calculated as the ratio of the total number of people who die due to all causes over a specific time period to the total number of people in the selected population. Measures of Health Status (Mitral Regurgitation)
  • P ( mitral valve Mitral valve The valve between the left atrium and left ventricle of the heart. Heart: Anatomy Prolapse)
  • V (V SD SD The standard deviation (SD) is a measure of how far each observed value is from the mean in a data set. Measures of Central Tendency and Dispersion)
  • TR (Tricuspid Regurgitation)
  • A (Aortic stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS))
  • PS PS Invasive Mechanical Ventilation (Pulmonic Stenosis)
• Diastolic murmurs: “MS. PAR-TS”
  • MS MS Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease that leads to demyelination of the nerves in the CNS. Young women are more predominantly affected by this most common demyelinating condition. Multiple Sclerosis (Mitral Stenosis)
  • P (Pulmonary regurgitation Regurgitation Gastroesophageal Reflux Disease (GERD))
  • AR AR Aortic regurgitation (AR) is a cardiac condition characterized by the backflow of blood from the aorta to the left ventricle during diastole. Aortic regurgitation is associated with an abnormal aortic valve and/or aortic root stemming from multiple causes, commonly rheumatic heart disease as well as congenital and degenerative valvular disorders. Aortic Regurgitation (Aortic Regurgitation)
  • TS (Tricuspid Stenosis)