As a result of mitral regurgitation, blood flows back from the left ventricle to the left atrium because the mitral valve does not close properly. Symptoms such as shortness of breath, fatigue, and palpitations can result from a reduction in the amount of blood pumped to the body. There are a variety of factors that can cause mitral regurgitation, such as congenital defects, rheumatic fever, or aging. We will discuss the causes, symptoms, diagnosis, treatment, and prevention of mitral regurgitation in this blog post.
Between the left atrium and left ventricle of the heart is the mitral valve. Mitral valves have two flaps, called leaflets, that open and close to control blood flow. When the left ventricle contracts, the mitral valve should close tightly to prevent blood from leaking back to the left atrium. However, mitral regurgitation occurs when the valve does not seal completely, causing some blood to return.
Mitral regurgitation can be classified into two types: primary and secondary. Primary regurgitation occurs when there is a problem with the valve itself, such as:
The leaflets of the mitral valve bulge or sag into the left atrium, causing a gap between them.
Stenosis of the mitral valve occurs when the leaflets become thickened, stiff, or fused, narrowing the valve opening.
Calcium deposits form on the leaflets of the mitral valve, reducing their flexibility and mobility.
Bacteria, fungi, or other microorganisms inflame or damage the leaflets of the mitral valve.
As a result of trauma, heart attack, or other causes, the leaflets of the mitral valve tear or break.
In secondary mitral regurgitation, the heart muscle or surrounding structures are affected, such as:
During dilated cardiomyopathy, the left ventricle becomes enlarged and weak, causing the valve to separate.
As a result of reduced blood supply, the left ventricle becomes scarred and stiff, altering the shape and function of the valves.
In hypertrophic cardiomyopathy, the left ventricle becomes thickened and stiff due to genetic or acquired factors, obstructing the valves.
A left ventricular aneurysm occurs when the left ventricle develops a bulge or hole following a previous heart attack.
Chronic mitral regurgitation develops gradually over time and may not cause symptoms for a long time. Acute mitral regurgitation can be life-threatening. It is usually caused by a ruptured valve or an infection. Chronic mitral regurgitation is usually caused by degeneration or dilation of the valve.
Mitral regurgitation symptoms vary depending on severity and duration of the condition. Some common symptoms include:
Exertion or lying down can cause shortness of breath
Dizziness, fatigue, or weakness
A rapid, pounding, or irregular heartbeat, or palpitations
Foot, ankle, or leg swelling
A cough, especially at night or while lying down
Pain or discomfort in the chest
Fainting or low blood pressure
A doctor will examine your heart and ask you about your medical history and symptoms to diagnose mitral regurgitation. A characteristic whooshing sound, known as a murmur, can be heard when the valve leaks. A stethoscope will also be used to listen to your heart sounds.
A doctor may also order tests to confirm the diagnosis and assess the severity and cause of the condition, such as:
Echocardiogram: An echocardiogram uses sound waves to create images of the heart and its valves. It measures the size and shape of the heart chambers, the function of the heart muscle, and the degree of valve leakage.
The electrocardiogram (ECG) records the electrical activity of the heart. It can detect abnormal heart rhythms, signs of heart damage, and enlarged heart chambers.
This test uses radiation to produce images of the chest. It can reveal the size and shape of the heart and lungs, as well as the presence of fluid or infection.
A cardiac MRI creates detailed images of the heart and its valves using magnetic fields and radio waves. It can provide information about the heart's structure and function as well as the severity of regurgitation.
An X-ray of the heart and its valves is produced by inserting a thin, flexible tube, called a catheter, into a blood vessel and guiding it to the heart. A dye is injected through the catheter to make the heart and its valves visible. It measures the pressure in the heart and the blood flow in the arteries and detects blockages or abnormalities.
Patients with mitral regurgitation are treated according to the cause, severity, and symptoms of the condition. The main goals of treatment are to relieve symptoms, prevent complications, and improve quality and length of life.
Medications can help control symptoms and complications of mitral regurgitation, including high blood pressure, heart failure, and arrhythmias.
A diuretic is a drug that reduces fluid retention and swelling in the legs and lungs.
Angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs): These drugs lower blood pressure and reduce heart workload.
A beta blocker slows down the heart rate, lowers blood pressure, and prevents or treats arrhythmias.
Drugs that prevent blood clots from forming in the left atrium and causing strokes.
Blood clots can form on valves or in arteries, causing heart attacks or other problems if they are not treated with antiplatelets.
Typically, surgery is recommended for severe or symptomatic mitral regurgitation, or when heart function is impaired. It is an invasive procedure that involves repairing or replacing the damaged valve. Surgery can improve patients' symptoms, prevent further heart damage, and improve survival. Types of surgery include:
In valve repair, the native valve is preserved and its function is restored. Various techniques can be used, such as:
It is necessary to reshape or trim the valve leaflets in order for them to close properly.
Repairing holes or tears in valve leaflets by stitching or patching.
Supporting the valve structure by tightening or replacing the valve ring.
Reattaching or strengthening the chordae tendineae to prevent the valve from prolapsing.
To improve valve alignment and movement, the papillary muscles are relocated or removed.
During a valve replacement procedure, the diseased valve is removed and a new one is installed. Biological or mechanical valves can be used to replace the diseased valve. Mechanical valves are durable and last longer, but require lifelong anticoagulant use to prevent blood clots. Animal or human tissues are used in biological valves, which do not need anticoagulants, but wear out faster and need to be replaced more often.
During catheter-based procedures, a catheter is inserted into a blood vessel and guided to the heart in order to repair or replace a valve. Devices are delivered through the catheter to repair or replace the valve. Catheter-based procedures are usually reserved for patients who cannot undergo surgery or are at a high risk of complications.
The mitral valve clip reduces leakage by clipping the valve leaflets together. The device can improve symptoms and quality of life, but it may not be effective for severe or complex mitral regurgitation cases.
Transcatheter mitral valve replacement (TMVR): This device replaces the old mitral valve with a new one without removing it. It can be an option for patients who have failed previous valve repair or who have a high risk of surgery. The procedure is still experimental and is currently not widely available.
Some cases of mitral regurgitation cannot be prevented, such as those caused by congenital defects or aging. However, some general measures may help reduce the risk or delay the progression of mitral regurgitation, including the following:
Controlling risk factors for heart disease, such as high blood pressure, high cholesterol, diabetes, obesity, and smoking.
Maintaining a healthy diet low in salt, fat, and sugar, and high in fruits, vegetables, whole grains, and lean proteins.
Maintaining a healthy weight and exercising regularly.
Consuming alcohol and illicit drugs in moderation.
Vaccination against infections that can affect the heart, such as influenza and pneumococcus.
Taking antibiotics before dental or surgical procedures that may cause bacteria to enter the bloodstream and infect the valve.
Following the prescribed treatment plan and having regular check-ups with your doctor.
