What is a Heart Murmur? A heart murmur is a sound that is picked up when listening to the heart with a stethoscope. In general heart murmurs are felt to represent possible underlying issues with heart valves. The sound of a heart murmur itself is related to patterns of blood flow through the heart and related turbulence that produces noise then picked up by a stethoscope. The presence of a heart murmur may or may not point to underlying issues in the heart that need further evaluation.
I see a lot of patients who have been told they had a heart murmur and it turns out to be nothing significant at all. I also see many patients who had been told they had a heart murmur that then go on to have significant issues that require further evaluation and treatment. The murmur itself may provide many clues as to the underlying diagnosis however in general a heart murmur leads to use of other tests such as an echocardiogram to help make a diagnosis.
What is a Heart Murmur In a Little More Detail?
When we put a stethoscope on the chest to listen to the heart we are essentially acquiring mechanical vibrations from the surface of the body. As you can imagine, increased turbulence would lead to increased noise in the form of vibration. Take a normal heart valve for example. It opens and closes and blood goes across it with each beat of the heart. The size of the valve is adequate for the blood to get across and the turbulence and therefore the noise is limited. So we generally wouldn’t hear a heart murmur. Now imagine that valve was tight. With every heartbeat, blood would still have to get across it, however the valve area is small and so there is much more turbulence created as the same amount of blood goes across a smaller valve. This turbulence generates vibrations and subsequent noise that is picked up by the stethoscope as a heart murmur.
Symptoms Associated With Heart Murmurs
Of course in the case of innocent heart murmurs, symptoms will not be associated. With murmurs that represent underlying heart disease however a number of symptoms related to this may occur. These include fatigue, decreased exercise tolerance, swelling, shortness of breath, passing out or chest pains amongst other symptoms.
Different Types of Heart Murmur
There are many different types of heart murmur that represent different underlying heart issues, usually valve issues. The location, timing, pitch and other characteristics of the heart murmur are critical in determining the significance and associated diagnosis. The murmur will often differ in the case of a tight or leaky valve. There are also other murmurs such as continuous murmurs that represent issues other than valve disease. When the heart is in a high flow state, for example during illness, pregnancy or other reasons, the high flow may generate a heart murmur that is simply a function of the flow rather than an issue with a heart valve. Training in auscultation for healthcare providers will allow them to pick up many murmurs however only those with advanced training and an interest in auscultation will be masters at picking up most murmurs and their associated diagnoses.
Causes of Heart Murmurs
Innocent murmurs – these are those such as childhood murmurs and those heard during the increased flow state of pregnancy
Flow Murmurs – include those heard in high output states such as thyroid disease or low blood levels of anemia
Holes in the heart – such as atrial septal defect and ventricular septal defect
Congenital heart disease – such as the continuous flow murmur of patent ductus arteriosus
I Have A Heart Murmur – Now What?
If your healthcare provider newly picks up the murmur then one of two things will usually happen. If they have access to ordering an echocardiogram they will send you for one of those. If not they will send you to a heart specialist to further evaluate. The heart specialist will typically order an echocardiogram also. The echocardiogram will look at underlying structure and function of the heart and will typically answer the question of murmur significance.
Heart Murmur – Summary
Heart murmurs are vibrations picked up by stethoscopes that may represent underlying heart disease. Many heart murmurs will be innocent and of no concern whereas others may represent issues such as heart valve disease. Often those with a heart murmur will be sent for a test called an echocardiogram to evaluate the underlying structure and function of the heart and determine the significance of the heart murmur.