Is it always necessary to investigate a heart murmur detected on physical examination?

From the Guidelines

Not all heart murmurs require further evaluation or treatment, and the decision to address a heart murmur should be based on its characteristics, associated symptoms, and patient risk factors, as outlined in the guidelines by the American College of Cardiology and American Heart Association 1. The evaluation of a heart murmur may vary greatly depending on many considerations, including the timing of the murmur in the cardiac cycle, its location and radiation, and its response to various physiological maneuvers. Some key points to consider when evaluating a heart murmur include:

• The presence or absence of cardiac and noncardiac symptoms
• Other findings on physical examination that suggest the murmur is clinically significant
• The intensity of the murmur, with louder murmurs (grade 3/6 or higher) potentially indicating a more significant underlying condition
• The type of murmur, with diastolic or continuous murmurs often requiring further evaluation
• The patient's age, medical history, and presence of symptoms, which can influence the decision to pursue further evaluation or treatment.

According to the guidelines, patients with diastolic or continuous heart murmurs not due to a cervical venous hum or a mammary souffle during pregnancy are candidates for echocardiography 1. Additionally, an echocardiographic examination is recommended for patients with apical or left sternal edge holosystolic or late systolic murmurs, for patients with midsystolic murmurs of grade 3 or greater intensity, and for patients with softer systolic murmurs in whom dynamic cardiac auscultation suggests a definite diagnosis (e.g., hypertrophic cardiomyopathy) 1. However, for patients with grade 1 or 2 midsystolic murmurs who are asymptomatic and have an otherwise normal cardiac examination, an extensive workup may not be necessary, as outlined in the guidelines 1. The decision to address a heart murmur should be based on a thorough clinical evaluation, taking into account the murmur's characteristics, the patient's overall health, and the presence of any symptoms or other abnormal findings, as recommended by the American College of Cardiology and American Heart Association 1.

From the Research

Heart Murmurs Evaluation

• Not all heart murmurs require immediate attention or further evaluation, as some may be innocent or functional 2
• However, certain types of murmurs, such as diastolic murmurs, loud or harsh-sounding murmurs, or those that radiate to the back or neck, may indicate underlying valvular pathology or other cardiac conditions and require further investigation 3, 2
• In infants and children, the presence of a murmur can indicate conditions ranging from no discernable pathology to acquired or congenital heart disease, and evaluation by a pediatric cardiologist is often necessary 2

Factors Influencing Evaluation

• The type and characteristics of the murmur, as well as the patient's symptoms and medical history, play a crucial role in determining the need for further evaluation 3, 2
• Echocardiography is a primary means of evaluating heart murmurs, and other tests such as electrocardiography and chest radiography may be used in certain cases 4
• Emerging technologies, including phonocardiography interpretation of murmurs and artificial intelligence algorithms, may also be used to differentiate innocent from pathologic murmurs 2

Management and Treatment

• The management and treatment of heart murmurs depend on the underlying cause and severity of the condition, and may involve medications such as metoprolol or verapamil to reduce symptoms and improve quality of life 5, 6
• In some cases, further intervention or surgery may be necessary to address underlying cardiac conditions or valvular pathology 3, 6