The “murmur” in the heart is an aural finding that the doctor hears with the stethoscope. It is due to the turbulent blood flow which in some cases is caused by a mechanical alteration in the structure of the heart.

There are also simpler causes such as fever, anemia, hyperthyroidism, pregnancy and vigorous exercise. In children there are some specific congenital heart diseases that usually involve abnormal communication between the chambers of the heart. In adults the murmur is usually related to a disease of the heart valves and to a lesser extent to an abnormal communication between chambers. The diagnosis is usually established by an ultrasound of the heart also known as a “triplex”. Below we will analyze the main causes in adults.

Stenosis of the Aortic Valve

Of all the conditions that cause a murmur, aortic valve stenosis is the most common that will land the patient in the operating room for surgery.

In aortic valve stenosis, the valve has accumulated calcium “salts” that prevent it from opening fully. Because of this, the heart finds it difficult to push the blood out of it towards the circulation. It is usually caused by atherosclerosis with risk factors of hypertension, cholesterol, diabetes, and kidney dysfunction. Symptoms of the condition are shortness of breath, dizziness, and syncope episodes. The treatment consists of replacing the valve which can now be done in multiple ways, either with a small surgical incision or completely percutaneously, as is done by coronary angiography. The anatomical and clinical characteristics of each patient will determine the most appropriate treatment.

Mitral Valve Insufficiency

Mitral regurgitation is the most common valvular disease and the second most common reason for a patient with a murmur to require surgery. In the condition this valve is ‘loose’ allowing blood to back up in the wrong direction (to the lungs) when the heart contracts. In most cases, there is no clear cause of the condition and it is also seen in younger patients compared to other valvular diseases. In a small percentage of patients it may be due to an infection, rheumatic fever, or even a previous heart attack. Patients will experience shortness of breath during exercise, fluttering with accompanying arrhythmia and easy fatigue. Treatment usually consists of valve repair preserving the patient’s tissue and without the long-term need for anticoagulants. In a few cases it may be necessary to replace the valve, either with a biological valve made from treated animal tissue, or with a mechanical valve. These operations can now be performed minimally invasively endoscopically or robotically.

Atrial Deficiency

In this condition there is communication between two chambers of the heart (right and left atrium). It is considered congenital heart disease (from birth) but especially in small deficits it may not be noticed until adulthood. This communication leads to a swelling of the heart from abnormal blood flow. The murmur is caused by the abnormal flow of blood from the left atrium to the right atrium. Patients often have shortness of breath with fatigue and fluttering, and there is also an association with repeated respiratory infections. Now, this condition can be corrected minimally invasively, either with an endoscopic operation or with a completely percutaneous treatment. The anatomical characteristics of the “deficit” between the two cavities usually determine the most appropriate treatment.

Other Valve Diseases

In aortic valve insufficiency there is “loosening” of the aortic valve. This condition is often associated with an aortic aneurysm. In some cases valve repair can be performed but in many cases there is poor tissue quality and the valve will need to be replaced.

Mitral valve stenosis is usually caused by rheumatic fever after strep throat in childhood. The valve has become quite narrow and does not allow blood to pass through the heart. In most cases, replacement with a biological or mechanical valve will be required.

Tricuspid valve insufficiency is a very common condition and in a small percentage of patients it will progress to severe insufficiency with the accompanying symptom of swelling of the lower limbs. If the condition is left untreated, it will lead the patient to right heart failure, arrhythmia (atrial fibrillation), pulmonary hypertension and cirrhosis of the liver. The valve is repaired using a technique known as annuloplasty which can be performed endoscopically on a beating heart.

in conclusion

There are a wide variety of conditions that cause murmurs. Some of them will need to be corrected by heart surgery to save the patient from the dangerous consequences of the condition. Fortunately, nowadays these operations can be done in a minimally invasive way or even percutaneously. For this reason, it is important for the patient with a murmur to undergo an ultrasound of the heart to determine the cause of the problem.