Heart valve disease is a condition where one or more of the heart’s four valves don’t open or close properly, disrupting the normal flow of blood through the heart. It affects millions of people worldwide, with cases of just one type (calcific aortic valve disease) rising from roughly 5 million to over 13 million globally between 1992 and 2021. Some people are born with a malformed valve, while others develop problems over decades as valves stiffen, thicken, or become damaged by infection.
How Heart Valves Work
Your heart has four valves, each acting as a one-way gate between chambers or between the heart and a major blood vessel. Every valve has a set of thin flaps called leaflets that snap open to let blood through, then seal shut so blood can’t flow backward. This opening and closing happens in sync with each heartbeat, thousands of times a day.
The four valves are:
- Tricuspid valve: sits between the right atrium (upper chamber) and right ventricle (lower chamber)
- Pulmonary valve: sits between the right ventricle and the artery leading to the lungs
- Mitral valve: sits between the left atrium and left ventricle
- Aortic valve: sits between the left ventricle and the aorta, the body’s main artery
When any of these valves fails to open fully, close completely, or is missing an opening altogether, the heart has to work harder to move blood. Over time, that extra workload can weaken the heart muscle and lead to serious complications.
Three Types of Valve Dysfunction
Valve problems fall into three categories based on what’s physically going wrong with the valve.
Stenosis means the valve opening has become too narrow. The leaflets may be thickened, stiff, or fused together, forcing the heart to push blood through a smaller gap. Aortic stenosis and mitral stenosis are the most commonly discussed forms. When the mitral valve narrows, it reduces or blocks blood flowing into the left ventricle, the heart’s main pumping chamber, making the heart work significantly harder with every beat.
Regurgitation (also called insufficiency or backflow) happens when a valve doesn’t seal tightly. Blood leaks backward instead of flowing forward. A leaky mitral valve, for example, allows blood to slip back into the upper chamber when the lower chamber contracts. The heart then has to pump the same blood twice, increasing its workload.
Atresia is the rarest and most severe form. The valve has no opening at all. A solid sheet of tissue forms where the valve should be, completely blocking blood flow. This is almost always a congenital defect, meaning a baby is born with it, and it requires intervention early in life.
What Causes Valve Disease
Some valve problems are present at birth. Congenital valve defects form during fetal development when the heart’s structure doesn’t develop normally. A baby might be born with leaflets that are the wrong size, shaped incorrectly, or not attached to the heart wall properly.
Most valve disease, however, develops over a lifetime. The aging process itself is a major driver. Calcium deposits gradually build up on valve leaflets, making them stiff and thick. This is why the burden of valve disease gets progressively worse with age, and why men tend to have higher rates of disease overall, though women over 85 face higher mortality from it.
Infections are another significant cause. Rheumatic fever, a complication of untreated strep throat, can scar valve tissue permanently. This remains the most common cause of mitral valve stenosis worldwide. Endocarditis, an infection of the heart’s inner lining typically caused by bacteria entering the bloodstream, can also erode or destroy valve leaflets. Good dental and skin hygiene helps reduce the risk of endocarditis, and finishing a full course of antibiotics for strep throat helps prevent rheumatic fever.
Other forms of heart disease can damage valves indirectly. When the heart enlarges from high blood pressure or a previous heart attack, the structures supporting the valve leaflets can stretch or shift, preventing the valve from closing properly.
Symptoms and How They Progress
Mild valve disease often produces no symptoms at all. Many people live for years without knowing they have a valve problem. A doctor might first detect it as a heart murmur, an unusual whooshing sound heard through a stethoscope during a routine exam.
As the disease progresses, symptoms typically emerge because the heart can no longer compensate for the faulty valve. The most common signs include shortness of breath (especially during physical activity or when lying down), fatigue and weakness that seem out of proportion to your activity level, swelling in the ankles, feet, or abdomen, dizziness or lightheadedness, and chest pain or tightness. An irregular heartbeat is also common, particularly with mitral valve problems, because the upper chambers can stretch and develop abnormal rhythms.
The pace of progression varies widely. Some people remain stable for decades with mild valve disease. Others deteriorate over a few years. Severe symptomatic aortic stenosis has a particularly grim trajectory if left untreated: once symptoms like shortness of breath or chest pain develop, average life expectancy drops to just one to two years. That prognosis is worse than most cancers, which is why identifying and treating severe valve disease promptly matters so much.
How Valve Disease Is Diagnosed
The echocardiogram is the most common and most important test for diagnosing valve problems. It’s painless and uses sound waves to create real-time moving images of your heart. The images show the size and shape of the heart, how well it’s pumping, and whether valves are opening and closing correctly. A specific type called Doppler ultrasound tracks blood flow through each valve, revealing leaks or blockages that wouldn’t be visible otherwise. An echo can also pick up blood clots, fluid buildup around the heart, and problems with the aorta.
An electrocardiogram (EKG) is often done alongside the echo. It records the heart’s electrical activity and can show whether the heart is beating too fast, too slowly, or irregularly. While an EKG can’t diagnose valve disease directly, it reveals the downstream effects, like an abnormal rhythm caused by a stretched heart chamber. In some cases, additional imaging or a procedure where a thin tube is threaded into the heart through a blood vessel may be needed to get more detailed measurements of pressure and blood flow.
Treatment: Repair vs. Replacement
Not every valve problem needs surgery. Mild or moderate disease is often managed with regular monitoring and medications that reduce symptoms or ease the heart’s workload. But when valve disease is severe or causing significant symptoms, the valve itself needs to be fixed.
Surgeons generally prefer to repair a valve when possible, because keeping your own tissue tends to produce better long-term results. Repair might involve reshaping leaflets, patching holes, or tightening the ring of tissue that supports the valve. However, repair isn’t always feasible. Valves that are heavily calcified, severely scarred by rheumatic disease, or destroyed by infection may need to be replaced entirely.
Replacement valves come in two main types. Mechanical valves are made of durable synthetic materials and can last a lifetime, but they require you to take blood-thinning medication permanently to prevent clots from forming on the artificial surface. Tissue valves, made from cow or pig heart tissue, don’t require long-term blood thinners but wear out over time and may eventually need to be replaced again. Tissue valves are generally preferred for older patients, while mechanical valves are often chosen for younger patients who can manage lifelong blood-thinning therapy.
Minimally Invasive Options
Traditional valve surgery requires opening the chest through a long incision down the breastbone. For patients who are too frail or too high-risk for open-heart surgery, a less invasive approach called transcatheter aortic valve replacement (TAVR) offers an alternative. During TAVR, a doctor inserts a thin flexible tube into a blood vessel, usually in the groin or chest, and guides it to the heart. A new valve made of animal tissue is compressed onto the tip of the tube, threaded into position, and expanded inside the old valve using a balloon or a self-expanding frame.
TAVR patients typically have shorter hospital stays and faster recovery times than those who undergo open-heart surgery. Studies have found that the risks of stroke and death are similar between TAVR and traditional surgical replacement, making it a viable option for a growing number of patients. Originally reserved for people who couldn’t tolerate open surgery, TAVR is now used across a wider range of patients with aortic stenosis.