A heart murmur refers to an abnormal sound – variously described as a whooshing, swishing, rasping or blowing noise – created when blood moves through the heart. The sound is most often caused by a heart valve that doesn’t open or close properly. Here's what you need to know about heart murmurs.
1. Having a heart murmur doesn’t mean you have heart disease.
About 61 per cent of heart murmur cases referred to a specialist are described as "innocent," which means they don't affect heart function, says Dr. Andreas Wielgosz, a cardiologist at the University of Ottawa and spokesperson for the Heart and Stroke Foundation. Up to 60 per cent of children will have a heart murmur at some stage, but the murmur will typically go away as the child grows. For example, a child born with a small hole on the inside wall of her heart may have a heart murmur, but as she grows and the hole closes, the murmur will likely disappear. In adults, innocent murmurs can also occur temporarily if their blood flows faster or harder than usual, for example, during pregnancy or while battling a fever. In cases of innocent heart murmurs, a doctor may order an echocardiogram to monitor the condition and rule out serious heart valve malfunction.
2. Heart murmurs are graded from 1 to 6, depending on how loud they are.
A Grade 1 murmur is barely audible with a stethoscope, while a Grade 6 murmur is audible without one. Grades 4 through 6 are accompanied by a vibration, or "thrill." But don't assume you’re in the clear if your murmur has a low grade. The location of the heart murmur is usually more important than the grade in determining the seriousness of the problem, says Wielgosz
Page 1 of 23. There are four types of heart murmurs.
A heartbeat occurs when the heart valve opens and shuts to let blood pass into the different chambers. In addition to innocent murmurs, there are three types of abnormal murmurs, each occurring at a different stage of the heartbeat cycle. These are:
• Systolic (occurs as the heart muscle contracts between beats);
• Diastolic (occurs as the heart muscle relaxes between beats); and
• Continuous (occurs throughout the heartbeat cycle).
4. Treatment of noninnocent heart murmurs depends on the underlying problem and varies widely.
Surgery may be needed to patch a hole, fix or replace a valve, or rebuild or widen a vessel. Drugs may help reduce the heart's extra workload caused by the murmur or help prevent blood clots. Antibiotics may be required before a medical or dental procedure to lower the risk of blood-borne bacterial infections that are caused by roughened tissues that trap bacteria to the heart’s walls. If, on the other hand, there are no symptoms (chest pains, heart palpitations or breathlessness), your condition may only need monitoring.
Signs of an abnormal murmur in your child
Does your infant show any of these symptoms? If so, check with your doctor to see if your child has a heart murmur.
• Feeding intolerance (diarrhea, blood in the stools, vomiting)
• Failure to thrive (inability to gain weight)
• Respiratory symptoms (coughing)
• Bluish discoloration of the skin and mucous membranes (caused by cyanosis, a lack of oxygen in the blood)
Additonal signs to look for in older children:
(over the age of seven):
• Chest pain
• Difficulty breathing during exercise
• Temporary loss of consciousness (fainting, also called "syncope")
See the doctor if:
• There is a family history of heart disease, abnormal cardiac function or of sudden death at a young age.
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