While a heart murmur in a toddler can sound concerning, it is often a common and harmless finding, frequently a normal part of a child’s development. Heart murmurs are simply sounds made by blood flowing through the heart and its vessels, not inherently a sign of disease. This article provides clarity and reassurance about heart murmurs, particularly when a toddler is sick.
Understanding Heart Murmurs
A heart murmur is an extra sound, distinct from the typical “lub-dub” of a heartbeat, that a doctor can hear using a stethoscope. This sound, often described as a whooshing or swishing, occurs due to turbulent blood flow within the heart or its connecting blood vessels.
Normally, blood flows smoothly through the heart’s chambers and valves. If this flow becomes less smooth, it can create vibrations audible as a murmur. The heart’s valves ensure one-way blood movement, and their closing produces normal heartbeat sounds. Increased speed or changes in blood flow direction can generate these additional sounds. Doctors listen to the heart in different areas of the chest to detect these sounds and assess their characteristics.
Why Sickness Can Affect Murmurs
A heart murmur, whether previously identified or newly detected, can become more noticeable when a toddler is sick. Illness often leads to physiological changes that increase the speed and turbulence of blood flow, making an existing murmur more prominent. For instance, a fever elevates the body’s temperature and heart rate, causing blood to pump more rapidly and intensifying the murmur’s sound.
Conditions like anemia, characterized by a low red blood cell count, can also affect blood thickness, leading to increased blood flow and a louder murmur. Dehydration or an infection can also alter circulatory dynamics, causing a temporary increase in cardiac output. These changes do not indicate a new heart problem, but rather amplify the sound of an already present, often harmless, murmur. The murmur may then become quieter or even disappear once the child recovers and temporary physiological changes subside.
Distinguishing Innocent from Concerning Murmurs
Heart murmurs are categorized as either “innocent” (also called benign or functional) or “concerning” (pathological), with innocent murmurs being far more common in children. An innocent heart murmur is a sound made by a healthy heart and does not signify structural problem or disease. These murmurs are soft, brief, and often vary in intensity with changes in the child’s position, activity level, or breathing. They are frequently heard during periods of rapid growth or increased physical activity and usually do not cause other symptoms. Many innocent murmurs eventually fade or disappear as a child grows.
In contrast, a concerning murmur may indicate an underlying heart condition, often a structural issue present from birth, such as a hole in the heart or a problem with a heart valve. These murmurs may have a harsher quality, be louder (graded as 3 or higher on a scale of 1 to 6), or occur during specific phases of the heartbeat (e.g., diastolic or continuous, rather than just systolic). Unlike innocent murmurs, concerning murmurs are often accompanied by other symptoms that signal a potential cardiac issue, necessitating further evaluation.
When to Consult a Doctor
While most heart murmurs in toddlers are innocent, certain accompanying signs indicate a need for medical attention. Parents should consult a doctor if a murmur is noted alongside symptoms such as difficulty or rapid breathing. Other indicators include poor feeding, insufficient weight gain, or unusual fatigue.
Additional symptoms warranting prompt medical evaluation include excessive sweating, especially during feeding, and any bluish tint to the skin, lips, or fingertips. Dizziness, fainting, or chest pain are also significant signs requiring immediate assessment. Swelling in the legs, ankles, feet, or abdomen should also prompt a medical visit. A healthcare provider can assess the murmur’s characteristics and determine if specialized cardiac evaluation is necessary.