The human heart beats in a rhythmic pattern, making a lub dub sound. This sound is generated when the blood flows through the chambers or the heart valves. Normally, when the blood flows through the blood vessels, it does not make any noise. If besides the normal lub dub sound, a swishing sound is also heard, it is referred to as a heart murmur. In case of newborns, such swishing sounds could be due to the normal changes that take place in the blood circulation after birth. These sounds can be heard with the help of a stethoscope. The term 'innocent heart murmurs' refers to murmurs that are harmless. It means that the sounds are not due to any structural (anatomic) or functional (physiological) abnormalities of the heart. These are quite common in babies. However, these resolve on their own, and don't require treatment. Treatment is required, when the sounds are due to a congenital heart defect. The key is to ascertain if the abnormal sound is due to a heart condition such as a leaking or narrow heart valve, a narrow artery, a hole in the heart, etc. A heart murmur can be innocent (functional), congenital, or the result of a heart defect. There are no specific symptoms of such murmurs, other than the unusual sound made by the heart. However, in case of a congenital defect, a few symptoms might be observed. These include shortness of breath, feeding difficulty, chest infection, etc. In 90% of the cases, the murmur is of functional or innocent type. Hence, parents should not panic, if they hear such a sound. Innocent Murmurs Innocent/functional murmur can be observed in a healthy and normal heart. No special treatment is required for this type of murmur, as these don't pose any threat to the child. Abnormal Heart Murmur due to Structural Defects or Abnormalities This type is rare, and is a symptom of a heart problem. One in 100 babies is affected by this condition. In such cases, laboratory tests like electrocardiogram, chest X-ray, echocardiogram, etc., are performed. The health of the mother during pregnancy can influence the health of the baby. If the mother was affected by German measles or diabetes during pregnancy, or drank alcohol during pregnancy, then the risk of this condition increases. Abnormal murmurs could occur due to a structural problem in the heart. There are different types of heart defects. These include valve abnormalities, cardiomyopathy, and septal defects. Septal defects are characterized by the presence of holes in the heart walls. The hole can cause flow of extra blood into the heart, which in turn could cause abnormal swishing sounds. At times, valves become hard, and don't allow enough blood through them. In some cases, valves don't close properly and leak. These could also cause such abnormal heart sounds. In rare cases, infants might be affected by cardiomyopathy, a condition wherein the heart muscles are abnormally thick and weak, which in turn results in impaired functioning of the heart. The treatment depends on the underlying cause. Innocent or functional murmur does not require any type of treatment. If an infant is diagnosed with a congenital heart problem or heart defect, then the parents need to approach a pediatric cardiologist. Depending on the symptoms observed, the pediatric cardiologist provides the appropriate treatment. The aim of the treatment is to correct the defect and regulate the proper blood flow in the heart. The treatment might involve surgery or drug therapy. On a concluding note, innocent heart murmurs are quite common in babies, but these don't pose any health problem. However, if parents hear abnormal heart sounds, it's advisable to consult a pediatrician for determining the underlying cause and the suitable treatment. Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.