In many cases it is a benign condition, which can be detected occasionally during a normal medical examination in the pediatric age, during adolescence or adulthood, and does not correspond to any pathology. Other times it is associated with heart disease, which over time may cause relevant symptoms or clinical signs, and be properly treated. The condition is referred to as a heart murmur. We discuss the topic with Dr. Veronica Barbara Fusi, Cardiologist of Humanitas.
What is a heart murmur?
All you need to do is to use a stethoscope to listen to the heartbeat and discover the murmur. As the name itself suggests, this is an abnormal noise that indicates an alteration in the flow of blood through the heart valves inside the cardiac cavity or adjacent vascular structures, a blood flow that from laminar (and therefore silent) becomes turbulent (and thus perceived). Such blood flow turbulence may be related to congenital or acquired pathological cardiac conditions or to contingent, transient, or physiological extra-cardiac pathologies.
“The characteristics of the heart murmur, such as tone, intensity or its irradiation, their duration or timing of onset – explains Dr. Fusi – can help direct the specialist to the possible types of mechanism that cause the heart murmur and its possible severity. In order to hypothesize a cause, the doctor must also investigate any concurrent or previous pathologies, whether personal or in the family. In case a pathological heart murmur is suspected, it is recommended to perform a first level instrumental assessment such as the trans-thoracic Color Doppler echocardiogram. In some cases, it will be necessary to perform further second-level instrumental investigations, such as trans-esophageal echocardiogram, heart CT, cardiac MRI or cardiac catheterization.
The organic heart murmur
It is referred to as an organic, abnormal or pathological heart murmur when it is associated with congenital heart or large vessels malformations, or with changes in the structure or function of heart valves, alterations that may be of a congenital nature or even acquired during life as a result of infections, ischemic pathology or simple senile degeneration (congenital, post-ischemic or post-infectious cardiopathies, bicuspid aorta, mitral prolapse, ruptured tendon, senile valvular calcifications).
Patients may also have other symptoms of heart problems related to murmurs, from chest pain to palpitations, from dyspnea to lipothymia and exercise syncope. In children, it may manifest with difficulties in growth or loss of appetite or skin cyanosis. In other cases, especially if the disease is mild or if the etiology is not acute, cardiac murmur may not be associated with any symptoms.
The “innocent” heart murmur
On the other hand, when the affected individual has no cardiac or valve abnormalities, it is referred to as an innocent or functional heart murmur, as a consequence of high speed of blood flow through the valves or cardiovascular structures. There are several possible extra-cardiac causes that cause the transitory appearance of the functional murmur: from pregnancy to hyperthyroidism, from anemia to fever, from the physiological sinus tachycardia present in infants or children to tachycardia in anxious patients or patients with excessive stress, from the athlete’s sports heart to healthy people with lean constitution.
Therefore, heart murmur can be present from birth or it can appear over a lifetime, with or without relation to cardiac abnormalities. Usually, abnormal murmurs are larger than functional murmurs and have quite specific characteristics that allow them to be identified as pathological heart murmurs. A correct anamnestic collection by the doctor should be aimed at investigating any previous pathologies, infections or the presence of concomitant symptoms and/or signs, which could help to formulate a diagnosis of suspected pathological heart murmur.
What it means to have a heart murmur
In cases of functional heart murmur, it will not be necessary to resort to any targeted treatment of the cardiovascular system, as the heart is healthy. In a case of functional murmur with an associated condition, the treatment of the pathology or associated condition often results in the disappearance of the heart murmur as well. The murmur may in fact disappear with time or persist throughout life, without creating limitations or impacting the quality of life.
However, in cases of a pathological heart murmur, valve malfunction or underlying cardiac disease are likely to require periodic clinical and instrumental checks, adhesion to a pharmacological therapy, or it may lead to surgery or percutaneous intervention (e.g. repair or replacement of a malfunctioning cardiac valve or suture or positioning of a cardiac valve) depending on the clinical or hemodynamic analysis of the underlying pathology.
Does a functional heart murmur have limitations in terms of physical or sporting activity? “An innocent heart murmur – says Dr. Fusi – does not imply limitations in your daily activities or sports practice, precisely because it is not related to any structural cardiac or valve pathology. Only if we find ourselves in the presence of functional murmurs concomitant with extra-cardiac diseases that create limitations in making significant physical efforts or generalized malaise, it is considered appropriate to apply caution in competitive sports. Treatment of the underlying disease or condition (such as hyperthyroidism or fever) will result in the disappearance of the heart murmur”.
What changes for an individual who suffers from an abnormal heart murmur? “An organic murmur, even if mild, is by definition related to an anomaly of the cardiovascular system (heart, valves, emerging vessels), but it is not always associated with symptoms, which may appear when the underlying pathology is already moderate or severe”.
“Therefore, regardless of whether or not symptoms are present, an annual cardiac check-up is recommended, which will allow the physician to assess whether to schedule any instrumental follow-up examinations to monitor the possible progression of a pathology associated with a heart murmur (the color Doppler echocardiogram is the most frequently required examination). Moreover, an evaluation will also determine the necessity for medications (ACE inhibitors, betablockers, diuretics, antiarrhythmic, anticoagent) aimed at controlling cardiovascular risk factors and optimizing the hemodynamic balance, manage the symptoms and quality of life of the patient”.
“The progression of murmur-related heart or valve disease, especially if moderate or severe, is accompanied by a worsening of the patient’s symptoms and quality of life: pharmacological therapy is no longer sufficient and percutaneous or surgical intervention becomes the only option for treating the disease or correcting the specific defect “, concludes the expert.