Approach to a murmur (pediatrics): Clinical sciences

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Introduction0:00–0:24

A heart murmur is a sound produced by blood flowing through the heart and large vessels. While innocent murmurs are common in healthy infants and children, clues from the history and physical exam can identify pathological murmurs that require additional investigation.
Now, there are three main types of murmurs: systolic, diastolic, and continuous.If a child presents with a murmur, you should first perform an ABCDE assessment.

Unstable Patient0:24–0:52

If the patient is unstable, stabilize the airway, breathing, and circulation. Next, obtain IV access, consider IV fluids, and begin continuous vital sign monitoring, including blood pressure, heart rate, and oxygen saturation.
Finally, if needed, provide supplemental oxygen. Okay, now let’s go back to the ABCDE assessment and look at stable patients.

Stable Patient0:52–1:57

Your first step is to perform a focused history and physical exam. Physical examination will reveal a heart murmur, which you can characterize based on its location, timing and duration, quality, and intensity.
You can assign a grade to the murmur, according to its intensity, which can vary from I, which is barely audible, to grade VI, which can be heard with the stethoscope barely touching the chest wall.
In addition, be sure to note any positional changes in the murmur, and determine whether the murmur radiates to other locations.
Once you identify a heart murmur, assess for characteristics of an innocent murmur. These include a musical or vibratory quality, murmurs that are systolic, grade I to II out of VI, low-intensity and soft, and the absence of abnormal cardiac signs and symptoms.
If these characteristics are present, consider innocent murmurs. These include adolescent Ejection murmur, Carotid bruit, Still’s murmur, Peripheral pulmonic stenosis, and Venous hum.

Innocent murmurs1:57–4:09

To easily remember these innocent murmurs, think of the mnemonic Every Child Should Play Vigorously!A short crescendo-decrescendo murmur best heard at the right or left upper sternal border that typically does not radiate and becomes softer when the patient is upright is suggestive of an adolescent ejection murmur.Now, let’s move on to carotid bruits, which are detected over the carotid area.
The murmur classically produces a whooshing sound, with transmission to the skull or ear. These findings indicate the presence of a carotid bruit.Next up is a vibratory murmur, which is typically heard in children between 3 and 6 years old.
During Physical exam auscultation at the lower left sternal border, reveals a musical, vibratory, or humming systolic ejection murmur.
When your patient is lying supine, the murmur becomes louder, and if they sit upright or perform a Valsalva maneuver, its intensity decreases.
With these findings, you can diagnose a vibratory murmur.On the other hand, a peripheral pulmonic stenosis murmur is commonly detected in infants.
Physical exam at the left upper sternal border reveals a soft, low-pitched, blowing systolic ejection murmur. You may also notice the murmur radiating to the back or axillae.
With these findings, you can diagnose peripheral pulmonic stenosis.Finally, a venous hum can be detected at any age. It is best heard below the clavicle, and is characterized by a soft or low-pitched continuous murmur.
The murmur will disappear when your patient is in a supine position, or once they rotate their head to the side while seated upright.
With these findings, there’s a high chance that you’re hearing venous hum.Alright, let’s turn our attention to patients in whom characteristics of an innocent murmur are absent.

Pathologic murmurs4:09–4:32

Your next step should be to assess the timing of the murmur within the cardiac cycle. This means determining whether the murmur is systolic, diastolic, or continuous.
Let's first look at systolic murmurs.For a systolic murmur, proceed by assessing its timing within systole. If the murmur begins shortly after S1 and it has a crescendo-decrescendo pattern, your patient has a systolic ejection murmur.

Systolic ejection murmurs4:32–5:04

This should make you consider semilunar valve stenosis, which includes aortic and pulmonic valve, atrial septal defect, or hypertrophic cardiomyopathy.
Your next step should be to order an echocardiogram.Let’s first discuss aortic stenosis. Patients can present with exertional chest pain, dyspnea, or fatigue.

Aortic stenosis5:04–5:44

Physical exam will reveal a murmur at the right upper sternal border that may become softer during a Valsalva maneuver. Additionally, you may detect a thrill at the left sternal border, as well as an early ejection click.
Echocardiogram will reveal a stenotic aortic valve, and in some cases, a bicuspid aortic valve or left ventricular hypertrophy, which confirms the diagnosis of aortic stenosis.Next, let’s discuss pulmonic stenosis.
These patients may experience fatigue, exertional dyspnea, and syncope. Affected neonates might develop cyanosis if stenosis is severe.

Pulmonic stenosis5:44–6:24

Physical exam reveals a murmur at the left upper sternal border, and you may detect a loud S1 and a systolic ejection click, as well as a left parasternal lift.
Echocardiogram will demonstrate a stenotic pulmonic valve, and occasionally right ventricular hypertrophy, which confirms the diagnosis of pulmonic stenosis.
Now let’s discuss atrial septal defect, or ASD. This is often asymptomatic, although children with large defects may develop fatigue and exercise intolerance.

ASD6:24–7:01

Physical exam reveals a murmur at the left upper sternal border, with fixed splitting of S2. Sometimes, you’ll detect a diastolic rumble at the lower left sternal border.
If echocardiogram shows left-to-right flow across an atrial septal defect, possibly with right atrial enlargement, diagnose ASD.
Finally, there’s hypertrophic cardiomyopathy, or HCM. This is frequently asymptomatic, but may present with atypical chest pain.

HCM7:01–7:52

History may reveal unexplained syncope or episodes of nonsustained ventricular tachycardia, and family history could be significant for sudden cardiac death.
Physical exam will reveal a murmur at the left lower sternal border. The murmur increases in intensity with the Valsalva maneuver and while standing.
Echocardiogram will reveal a left ventricular wall thickness that’s 2 or more standard deviations above the mean for age and sex, which is highly suggestive of HCM.
You can confirm the diagnosis with genetic testing.Now let’s switch gears and discuss holosystolic murmurs, which you should suspect if the beginning of the murmur coincides with S1, and the murmur can be heard throughout systole.

Holosystolic murmurs7:52–8:19

If this is the case, your patient has a holosystolic murmur. This should make you consider ventricular septal defects as well as mitral and tricuspid regurgitation, and order an echocardiogram.First up are ventricular septal defects, or VSDs.
These are often asymptomatic if the lesion is small and muscular. Children with large defects may develop symptoms of heart failure, such as dyspnea or difficulty feeding.

VSD8:19–9:10

Physical exam reveals a murmur at the left lower sternal border that’s harsh, high-pitched, and confined to early systole if the defect is small, but it will be quieter, lower-pitched, and holosystolic if the defect is large.
You may notice signs of heart failure, such as tachypnea or hepatomegaly. Echocardiogram will reveal a perimembranous defect or a muscular defect in the ventricular septum, confirming the diagnosis of VSD.Now, let’s move on to mitral regurgitation.
Affected patients may experience chest pain, fatigue, and exercise intolerance. Physical exam will reveal a blowing murmur at the apex, and you might palpate a thrill.

Mitral regurgitation9:10–9:37

Echocardiogram will demonstrate mitral valve regurgitation, occasionally with left atrial enlargement, which confirms the diagnosis.Finally, let’s discuss tricuspid regurgitation.
These patients may experience fatigue or weakness. Physical exam will reveal a soft, blowing murmur at the left lower sternal border that becomes louder with inspiration.

Tricuspid regurgitation9:37–10:05

Additionally, you may detect hepatomegaly or peripheral edema. Echocardiogram will demonstrate tricuspid valve regurgitation, confirming the diagnosis.Now, let’s switch gears again and discuss murmurs that occur in late systole.
Late systolic murmurs should immediately make you consider mitral valve prolapse, and order an echocardiogram.Patients with mitral valve prolapse are often asymptomatic, although some may report chest pain, palpitations, or fatigue.

Late systolic murmur10:05–10:20

Physical exam will reveal a murmur at the apex. The murmur becomes louder while standing and softer while squatting, and you may detect mid-systolic click.

Mitral valve prolapse10:20–10:53

Echocardiogram will demonstrate mitral valve prolapse, with or without regurgitation, which confirms the diagnosis. Now, let’s move on to diastolic murmurs, which are always pathologic.
Your next step is to assess the timing of the murmur within diastole. If you detect an early diastolic murmur, consider aortic and pulmonic regurgitation, and order an echocardiogram.First, let’s discuss aortic regurgitation!

Diastolic murmurs10:53–11:04

Affected patients may experience chest pain, fatigue, exercise intolerance, or even syncope. Physical exam reveals a high-pitched, blowing, decrescendo murmur at the right upper sternal border and the left sternal border.

Early diastolic murmurs11:04–11:14

In chronic disease, you may detect a low-pitched “Austin Flint” murmur at the apex, as well as a bounding, “water-hammer” pulse.

Aortic regurgitation11:14–11:52

Echocardiogram will reveal aortic regurgitation, which confirms the diagnosis. Next, let’s talk about pulmonic regurgitation.
This can occur in children with chronic pulmonary hypertension or after surgical repair of Tetralogy of Fallot; patients may experience fatigue, chest pain, and syncope.
Physical exam will reveal a murmur at the left upper sternal border, and you may detect bounding peripheral pulses. Echocardiogram will demonstrate regurgitation of the pulmonary valve, as well as right ventricular hypertrophy in severe cases.

Pulmonic regurgitation11:52–12:33

With these findings, you can diagnose pulmonic regurgitation.Now lets look at what to do if you detect a murmur in mid-to-late diastole.
In this case consider mitral or tricuspid stenosis, and order an echocardiogram. First, let’s discuss mitral stenosis.
This may occur in patients with a history of rheumatic fever who present with fatigue and dyspnea. Physical exam reveals a low-pitched, rumbling murmur at the apex, best heard in the left lateral decubitus position.

Mid/late diastolic - Mitral stenosis12:33–13:24

In addition, you will likely detect a loud S1 and an opening snap. Echocardiogram will demonstrate a stenotic mitral valve, occasionally with left atrial enlargement, confirming the diagnosis of mitral valve stenosis.On the flip side, patients with tricuspid stenosis may have a history of mild fatigue or palpitations, as well as lower extremity edema.
Physical exam will reveal a low-intensity murmur at the left lower sternal border, which becomes louder with inspiration.
Echocardiogram will demonstrate a stenotic tricuspid valve, occasionally with right atrial enlargement, confirming the diagnosis of tricuspid stenosis.

Tricuspid stenosis13:24–13:56

Finally, let’s discuss continuous murmurs. These should make you consider a patent ductus arteriosus, then order an echocardiogram.Finally, there’s PDA.
This typically occurs in preterm infants presenting with symptoms of heart failure, such as difficulty feeding. Physical exam classically reveals a machinery-like murmur at the left upper sternal border which radiates to the back.

Continuous murmur13:56–14:11

You’ll likely detect bounding peripheral pulses, and there might be signs of heart failure, such as tachypnea and hepatomegaly.

PDA14:11–14:47

Echocardiogram will identify the patent ductus arteriosus to confirm the diagnosis. Alright, as a quick recap… Innocent murmurs include adolescent ejection murmur, carotid bruit, Still’s murmur, peripheral pulmonic stenosis, or venous hum.
If you rule out innocent murmurs, assess the murmur’s timing. Systolic murmurs are subdivided into early ejection, holosystolic, and late systolic murmurs.
Early ejection murmurs are typically associated with aortic or pulmonic stenosis, ASD, and HCM. On the flip side, holosystolic murmurs are seen in conditions such as mitral or tricuspid regurgitation and VSD.

Review14:47–15:55

Finally, late systolic murmurs are suggestive of mitral valve prolapse. Next, diastolic murmurs can be divided into early and late murmurs.
Early diastolic murmurs suggest aortic or pulmonic regurgitation, while late diastolic murmurs suggest mitral or tricuspid stenosis.
Finally, continuous murmurs in infants suggest a patent ductus arteriosus. regurgitation and VSD Finally late systolic murmurs are suggestive of mitral valve prolapse Next diastolic murmurs can be divided into early and late murmurs Early diastolic murmurs suggest aortic or pulmonic regurgitation While late diastolic murmurs suggest mitral or tricuspid stenosis Finally continuous murmurs in infants suggest a patent ductus
Approach to a murmur (pediatrics): Video and Steps | Osmosis