What are the indications for referral for echocardiography (echo) in an infant presenting with a heart murmur?

From the Guidelines

Infants with heart murmurs should be referred for echocardiography if they have any of the following indications:

• Pathologic murmurs, such as those that are grade 3/6 or louder, diastolic or continuous murmurs, harsh systolic murmurs, or murmurs heard best at the upper left or right sternal border 1
• Concerning symptoms, including poor feeding, failure to thrive, cyanosis, respiratory distress, abnormal pulses, or hepatomegaly 1
• Abnormal cardiac examination findings, such as a heave or thrill, abnormal heart sounds, or an abnormal ECG or chest X-ray 1
• Family history of congenital heart disease or genetic syndromes associated with cardiac defects, such as Down syndrome or DiGeorge syndrome 1
• Cyanosis, respiratory distress, abnormal arterial pulses, or cardiac murmur in a neonate 1
• Loud or abnormal murmur or other abnormal cardiac finding in an infant or older child 1
• Failure to thrive in the presence of an abnormal or unusual cardiac finding 1
• Presence of a syndrome associated with cardiovascular disease and dominant inheritance or multiple affected family members 1

The eight indications for referral for echocardiography in an infant presenting with a murmur are:

1. Pathologic murmurs, such as those that are grade 3/6 or louder, diastolic or continuous murmurs, harsh systolic murmurs, or murmurs heard best at the upper left or right sternal border 1
2. Cyanosis, respiratory distress, abnormal arterial pulses, or cardiac murmur in a neonate 1
3. Loud or abnormal murmur or other abnormal cardiac finding in an infant or older child 1
4. Failure to thrive in the presence of an abnormal or unusual cardiac finding 1
5. Family history of congenital heart disease or genetic syndromes associated with cardiac defects, such as Down syndrome or DiGeorge syndrome 1
6. Abnormal cardiac examination findings, such as a heave or thrill, abnormal heart sounds, or an abnormal ECG or chest X-ray 1
7. Presence of a syndrome associated with cardiovascular disease and dominant inheritance or multiple affected family members 1
8. Dextrocardia, abnormal pulmonary or visceral situs 1

It is essential to note that early evaluation is crucial because many congenital heart defects can be asymptomatic initially but may lead to significant complications if not identified and managed promptly 1.

From the Research

Indications for Referral for Echocardiography in Infants with a Murmur

The following are indications for referral for echocardiography in infants presenting with a murmur:

• Diastolic murmurs 2, 3
• Loud or harsh-sounding murmurs 2, 3
• Holosystolic murmurs 2, 3
• Murmurs that radiate to the back or neck 3
• Signs or symptoms of cardiac disease 2, 3
• Family history of sudden cardiac death or congenital heart disease 3
• History of conditions that increase the likelihood of structural heart disease, such as maternal diabetes mellitus or certain genetic disorders 3
• Murmur characteristics that suggest pathology, such as maximal murmur intensity at the upper left sternal border or a systolic click 3

Echocardiography in Asymptomatic Neonates with a Heart Murmur

Echocardiography is recommended for evaluation of neonatal heart murmurs because these are more likely to be manifestations of structural heart disease 2, 4, 5. Studies have shown that a significant percentage of asymptomatic neonates with heart murmurs may have underlying congenital heart disease 4, 5.

Importance of Echocardiography in Diagnosing Congenital Heart Disease

Echocardiography provides a definitive diagnosis of congenital heart disease and is essential for evaluating any potentially pathologic murmur 3, 5. The use of echocardiography in diagnosing congenital heart disease in newborns with asymptomatic cardiac murmurs can lead to earlier detection and improved clinical outcomes 5.