Listening to Your Heart: Understanding the Second Heart Sound

Welcome to the second heart sound category of this website, where you will learn about various aspects of the second heart sound, including physiologically split, second heart sound with persistent splitting, second heart sound with fixed splitting, and an increase in aortic intensity, among others.

Before beginning this session, please ensure that you have completed the normal heart sounds and first heart sound sessions. It’s important to have a good understanding of normal heart sounds before moving on to the second heart sound.

To get the best listening experience, we recommend using high-quality headphones or earphones. Computer or phone speakers may not accurately reproduce some of the more subtle heart sounds.

The second heart sound is a short burst of auditory vibrations with varying intensity, frequency, quality, and duration. It’s produced by the closure of the aortic and pulmonary valves. The split-second heart sound (S2) is best heard at the pulmonic valve listening post since P2 is much softer than A2. A2 is usually much louder than P2 due to higher pressures in the left side of the heart.

Factors such as heart rate, sex, age, height, and weight have little to no effect on the splitting pattern of the second heart sound. However, around 15% of subjects exhibit fixed splitting of the second sound in either a supine or upright position, but not both.

In severe hypertension, a loud second heart sound may be prolonged and slurred, falsely mimicking a split S2.

Characteristics:

  • High-pitched sound with a shorter duration of 0.12s.
  • Sounds like D-U-B and is loud and sharp.
  • Frequency is 50 Hz.
  • Best heard over the left 2nd intercostal space, about 1.5 inches away from the midline.
  • Occurs after the Apex beat and carotid pulse, at the end of the T-wave of ECG.

Significance:

  • Indicates the end of ventricular systole and the beginning of ventricular diastole.
  • A clear 2nd HS indicates that the semilunar valves are closing properly, meaning there is no regurgitation.

In medical practice, it’s important to correctly diagnose and understand the case. Therefore, hearing the heart sounds correctly and identifying any abnormalities is crucial during auscultation. Prior practice with these sounds can be helpful in identifying abnormalities and improving accuracy.

This site can help you gain practice in auscultation and learn about different cases related to heart sounds. With regular practice, you can increase your self-confidence and be better equipped for future medical practices. This site will always be a reliable resource for learning about heart sounds.

Second Heart Sound – Physiologically Split 2

The second heart sound (S2) is typically produced by the closure of the aortic and pulmonary valves. Normally, these two valves close very closely in time, so the S2 is heard as a single sound. However, in some individuals, the closure of the aortic and pulmonary valves is delayed, resulting in a physiological split second heart sound.

A physiological split S2 is usually heard during inspiration and disappears during expiration. During inspiration, the intrathoracic pressure decreases, causing an increase in venous return to the right side of the heart. This increase in venous return causes a slight delay in the closure of the pulmonic valve, resulting in a split second heart sound. The aortic valve closure occurs normally.

The physiological split S2 is a normal variant and is usually not associated with any clinical significance. However, it can be a useful diagnostic clue in some clinical situations. For example, in conditions such as pulmonary hypertension or right bundle branch block, the delay in pulmonic valve closure is prolonged, resulting in a wider split S2.

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It is important to note that a fixed or paradoxical split S2 is abnormal and may be associated with various cardiac abnormalities. A fixed split S2 is heard consistently throughout the cardiac cycle, and may be seen in conditions such as atrial septal defect or right ventricular failure. A paradoxical split S2 is heard during expiration and disappears during inspiration, and may be seen in conditions such as left bundle branch block or aortic stenosis.

Second Heart Sound with Persistent Splitting

The second heart sound, or S2, is a medical term used to describe the sound made by the closing of the aortic and pulmonic valves in the heart. Normally, these two valves close simultaneously, producing a single sound. However, in some cases, there may be a delay in the closure of one of the valves, resulting in a persistent splitting of the S2 sound.

Persistent splitting of the S2 sound is most commonly caused by a delay in the closure of the pulmonic valve, which can occur due to a variety of conditions such as right bundle branch block, pulmonary hypertension, or aortic stenosis. This delay causes the pulmonic valve to close slightly later than the aortic valve, resulting in a splitting of the S2 sound that is heard throughout the cardiac cycle.

In most cases, persistent splitting of the S2 sound is not a cause for concern and does not require treatment. However, if the splitting is accompanied by other symptoms such as shortness of breath or chest pain, further evaluation may be necessary to determine the underlying cause and appropriate treatment.

Second Heart Sound with Fixed Splitting

The second heart sound (S2) is the sound produced by the closing of the aortic and pulmonary valves of the heart. In normal circumstances, S2 is a single sound, but in some conditions, it may be split into two distinct components.

Fixed splitting of S2 is a phenomenon where the two components of the second heart sound are consistently separated by a fixed time interval, regardless of the patient’s respiratory cycle. This occurs when there is a delay in the closure of the pulmonary valve relative to the aortic valve, resulting in a split that remains constant throughout the cardiac cycle.

One of the most common causes of fixed splitting of S2 is a congenital heart defect called atrial septal defect (ASD), where there is a hole in the wall (septum) that separates the two atria. In ASD, the increased blood flow to the right atrium leads to increased blood flow to the right ventricle and pulmonary artery, causing a delay in the closure of the pulmonary valve and a fixed splitting of S2.

Other causes of fixed splitting of S2 include right bundle branch block (RBBB), pulmonary hypertension, and tricuspid atresia. RBBB delays the contraction of the right ventricle, resulting in a delay in the closure of the pulmonary valve. Pulmonary hypertension and tricuspid atresia cause increased blood flow to the right side of the heart, resulting in delayed closure of the pulmonary valve.

Fixed splitting of S2 can be diagnosed by auscultation using a stethoscope. The diagnosis of the underlying condition causing fixed splitting of S2 requires further evaluation, such as echocardiography or cardiac catheterization.

Second Heart Sound: Fixed Splitting, Increased Aortic Intensity

The second heart sound (S2) is a crucial clinical finding in the diagnosis of various cardiac conditions. Fixed splitting of S2 is an abnormal finding that suggests delayed closure of the pulmonary valve and is often seen in conditions such as atrial septal defects and right bundle branch block. On the other hand, increased aortic intensity indicates increased flow across the aortic valve, which is commonly seen in patients with aortic stenosis or long-standing hypertension.

Hypertension is a significant risk factor for cardiovascular disease and can lead to an increase in left ventricular wall thickness, affecting the closure of the aortic valve. When auscultating for S2, the diaphragm of the stethoscope should be placed over the aortic region while the patient is in a sitting position. This allows for accurate detection of any abnormal sounds, including fixed splitting of S2 and increased aortic intensity.

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In summary, it is essential to understand the significance of fixed splitting of S2 and increased aortic intensity and their association with hypertension and other cardiac conditions. Accurate auscultation techniques can aid in the diagnosis of such conditions and help clinicians provide appropriate management to their patients.

Second Heart Sound: Fixed Splitting, Decreased Aortic Intensity

The second heart sound (S2) is the sound of the closing of the aortic and pulmonary valves, which occurs during the cardiac cycle. Normally, S2 has two components, A2 and P2, which correspond to the closure of the aortic and pulmonary valves, respectively.

“Fixed splitting” refers to a condition in which the interval between A2 and P2 does not change during the respiratory cycle. This can be caused by various cardiac conditions, such as atrial septal defect (ASD) or right bundle branch block.

“Decreased aortic intensity” refers to a condition in which the intensity or loudness of the A2 component of S2 is reduced. This can be caused by various factors, such as aortic stenosis or calcification, reduced cardiac output, or decreased blood volume.

When both fixed splitting and decreased aortic intensity are present, it can be an indication of aortic stenosis or other conditions affecting the aortic valve. However, a thorough evaluation by a healthcare professional is necessary to determine the underlying cause and appropriate treatment.

The second heart sound (S2) is composed of two components, A2 and P2, which correspond to the closure of the aortic and pulmonic valves, respectively. In fixed splitting, the interval between A2 and P2 does not change during the respiratory cycle, and the P2 component occurs after the A2 component. The decrease in afterload causes less resistance to the flow of blood from the left ventricle through the aortic valve, resulting in less regurgitation of blood into the mitral valve. This leads to a decrease in the intensity of the murmur and is indicative of reduced cardiac output.

To auscultate for this sound, the diaphragm of the stethoscope should be used, and the patient should be in a supine position while sitting and leaning forward. The fixed split S2 with decreased aortic intensity is best heard in the second intercostal space.

Second Heart Sound and Late Systolic Click

The second heart sound (S2) is a vital component of the cardiac cycle and is caused by the closure of the aortic and pulmonary valves. The sound is typically described as “dub” and is heard immediately after the T-wave on an electrocardiogram. S2 can be divided into two components: A2, which is produced by the closure of the aortic valve, and P2, which is generated by the closure of the pulmonary valve.

In some cases, an additional sound known as the late systolic click (LSC) may be heard. LSC is characterized by a sharp, clicking sound that occurs just before the second heart sound. It is caused by the sudden tensing of the chordae tendineae, which is the fibrous tissue that connects the papillary muscles to the mitral valve leaflets. The LSC sound can be mistaken for a split S2, which occurs when there is a delay in the closure of the aortic and pulmonary valves, resulting in a brief separation of the two components of S2.

It is important to differentiate between LSC and a split S2 as the underlying causes of these two sounds are different. The late systolic click is associated with degenerative activity in the mitral valve leaflet, which can lead to mitral valve prolapse (MVP). MVP is a common condition that affects up to 5% of the population and occurs when the mitral valve leaflets fail to close properly, resulting in blood flowing back into the left atrium. MVP is often asymptomatic but can cause chest pain, palpitations, and shortness of breath.

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On the other hand, a split S2 is caused by a delay in the closure of the aortic and pulmonary valves and is associated with conditions such as pulmonary hypertension and right bundle branch block. A split S2 is characterized by a brief interval between the A2 and P2 components of S2, which can be heard as two distinct sounds.

In summary, while the late systolic click and split S2 share similarities in auscultation, it is essential to differentiate between the two. The late systolic click disappears on the pulmonic area, and it is associated with degenerative activity in the mitral valve leaflet, while a split S2 is caused by a delay in the closure of the aortic and pulmonary valves and is associated with different underlying conditions.

Second Heart Sound and a Tumor Plop

The second heart sound followed by tumor plop is a rare heart sound configuration that can be mistaken for a split-second heart sound. This sound is produced by a tumor that obstructs the blood flow in the left ventricular outflow tract or the mitral valve, causing a characteristic sound during early diastole.

It is important to note that the tumor plop is not audible in the pulmonic area and can only be heard in the mitral region. This sound can be easily missed if not specifically looked for during auscultation.

The timing and frequency of the tumor plop mimic the third heart sound gallop. A third heart sound gallop is produced by rapid filling of the ventricles during early diastole and is associated with conditions such as congestive heart failure and cardiomyopathy. Therefore, it is crucial to differentiate between the two sounds during auscultation.

To properly detect a tumor plop, the patient should be in a supine position. The diaphragm of the stethoscope should be used to auscultate at the mitral region. The practitioner should listen for a low-frequency sound that follows the second heart sound.

It is essential to note that a tumor plop is a concerning finding and requires further investigation. It may indicate the presence of a cardiac tumor, which can be benign or malignant. Further diagnostic testing, such as echocardiography, is needed to confirm the diagnosis and guide treatment.

Opening Snap and Second Heart Sound

The opening snap is a prominent component of the cardiac cycle that is often heard during auscultation. It is a high-pitched sound that occurs in early diastole, typically just after the second heart sound. The sound is caused by the rapid opening of the mitral valve, and it is considered to be a diastolic sound.

The opening snap may be heard at the apex region after the aortic heart sound. If an opening snap occurs in early diastole along with a single second heart sound, it can imitate a split second heart sound.

The sound of an opening snap is usually caused by disease or thick leaflets of the valves. In particular, the most common cause of an opening snap is mitral stenosis, which is a condition that is characterized by a narrowing of the mitral valve. When the leaflets of the valve become thickened, they can be difficult to open, which produces a snapping sound.

The severity of the opening snap can provide important diagnostic information. If the thickening of the leaflets is severe, then the opening snap will be heard very early during the diastole on auscultation. In contrast, if the leaflets are only mildly thickened, then the opening snap will be heard later in diastole.

In addition to mitral stenosis, other conditions that can cause an opening snap include mitral valve prolapse, rheumatic heart disease, and infective endocarditis. The opening snap can be a valuable diagnostic tool for identifying these conditions and monitoring their progression over time.

Overall, the opening snap is a crucial component of cardiac auscultation that can provide important diagnostic information about the health of the heart

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