A “leaky heart valve” occurs when one of the heart’s four valves does not close completely, allowing blood to flow backward. Heart valves function like one-way doors, ensuring blood flows in a single direction through the heart’s chambers and out to the body. When a leak occurs, the heart must work harder to re-pump the blood that has flowed backward. This condition, also called valvular regurgitation, varies in severity and can strain the heart muscle over time.
How Healthy Heart Valves Work
The human heart is divided into four chambers, each controlled by a valve: the tricuspid, pulmonary, mitral, and aortic. These four valves are structured with flaps of tissue, called leaflets or cusps, that open and close precisely with each heartbeat. They ensure the circulation of blood is efficient and unidirectional.
As the heart muscle contracts, the valves open to allow blood to move into the next chamber or out to the body, and then they snap shut to prevent any backflow. The mitral and tricuspid valves control blood flow between the upper chambers (atria) and the lower chambers (ventricles). The aortic and pulmonary valves regulate blood flow out of the ventricles. This synchronized opening and closing is what propels oxygen-poor blood to the lungs and oxygen-rich blood to the rest of the body.
Defining Valvular Regurgitation
Valvular regurgitation refers to the malfunction where a valve’s leaflets fail to seal tightly when they should be closed. This incomplete closure results in a portion of the blood moving backward, or “regurgitating,” into the chamber it just left. For instance, if the mitral valve leaks, blood flows back into the left atrium as the left ventricle contracts to pump blood forward.
This backward flow significantly reduces the amount of blood that is pumped out to the body with each beat, lowering the heart’s efficiency. The heart must then compensate by increasing its force of contraction. This sustained, increased effort places a significant volume and pressure overload on the affected heart chambers, which can lead to enlargement and weakening of the heart muscle over time. The degree of the leak determines the strain on the heart, with severe regurgitation requiring intervention.
What Causes Valves to Leak
Damage to heart valves can arise from factors categorized as acquired or congenital. A common acquired cause is degeneration, where the valve tissue breaks down due to aging and long-term wear and tear, frequently seen in older adults. Conditions that increase the workload on the heart, such as high blood pressure, can also stretch the valve opening, preventing the leaflets from meeting properly.
Infections represent another significant cause, particularly infective endocarditis, where bacteria or other pathogens attack the inner lining of the heart and the valves, causing destruction or scarring of the leaflets. Rheumatic fever, often stemming from an untreated strep throat infection, can also lead to permanent scarring of the valves. Furthermore, congenital heart defects, which are structural problems present from birth, can mean a valve was formed incorrectly, making it prone to leaking throughout a person’s life.
Symptoms and Diagnosis
The symptoms of a leaky valve often develop gradually and are directly related to how much the backflow reduces the heart’s forward pumping capacity. Common complaints include fatigue, and shortness of breath, particularly during physical activity or when lying flat, due to fluid backing up toward the lungs. Other signs may include heart palpitations (a rapid or irregular heartbeat) and swelling, known as edema, often noticeable in the legs and feet.
Diagnosis frequently begins with a routine physical examination where a doctor listens to the heart with a stethoscope. The turbulent backflow of blood through the faulty valve creates an abnormal sound called a heart murmur, which is often the first indication of a problem. To confirm the diagnosis and assess the leak’s severity, the primary tool is the echocardiogram, which uses sound waves to create moving images of the heart. This non-invasive ultrasound allows physicians to directly visualize the valve’s motion, measure the amount of blood flowing backward, and evaluate the effect of the leak on the size and function of the heart chambers.
Managing and Repairing Leaky Valves
The approach to managing a leaky heart valve depends on the severity of the regurgitation and the presence of symptoms. For mild cases, especially those without noticeable symptoms, the primary strategy is watchful waiting, which involves regular monitoring with echocardiograms. Medications are frequently prescribed to manage symptoms and reduce the heart’s workload. These drugs typically include diuretics to reduce fluid buildup and blood pressure medications to ease the strain on the heart.
When the leak is moderate to severe, or if the heart function is declining, intervention is generally necessary to prevent irreversible damage. This often involves a procedure to either repair or replace the damaged valve. Valve repair aims to restore the valve’s function by tightening the ring around it or patching the leaflets. If repair is not possible, the valve is replaced with an artificial valve, which can be made from animal tissue or mechanical materials. These procedures can be performed through traditional open-heart surgery or increasingly through less invasive, catheter-based techniques.