Understanding Your Heart: What is Aortic Stenosis?
Aortic stenosis is a progressive heart disease that affects about 2%-9% of the general population. You can live a healthy, normal life with a mild case of aortic stenosis, but as the condition slowly worsens over the years, you’ll need the expertise of the experienced team at Advanced Cardiovascular Care to monitor your health and provide a valve replacement when needed.
What part of your heart is affected by aortic stenosis?
Your heart is divided into four chambers, two upper chambers called the left and right atria, and two lower chambers called the left and right ventricles. The atria receive blood, while the ventricles pump it out of your heart.
Blood must flow in a specific direction, so your heart has four valves to control the flow. They open to let blood go in the appropriate direction, then close to ensure it doesn’t flow back in the wrong direction.
The valves also control pressure inside the heart. As valves open and close, they allow each ventricle to completely fill with blood, which ensures enough pressure to properly pump blood.
Aortic stenosis develops in a valve associated with the left ventricle, the aortic valve. Your left ventricle receives freshly oxygenated blood, then pumps it through the aortic valve into the aorta — the artery that carries oxygen-rich blood toward the rest of your body.
What is aortic stenosis?
Aortic stenosis occurs when the aortic valve stiffens and doesn’t fully open the way it should, narrowing the valve opening. When this condition occurs, blood flow from your heart to your body is reduced or blocked.
While the left ventricle works harder to push blood through the valve, the extra stress eventually takes a toll, making the muscles thicken, then weaken. When the ventricle wall thickens, it takes up extra space, allowing less room for blood, a problem that can lead to heart failure.
What causes aortic stenosis?
Most cases of aortic stenosis come from one of two conditions: congenital bicuspid aortic stenosis or calcific aortic stenosis. Other possible but uncommon causes include rheumatic heart disease and radiation-induced aortic stenosis.
Congenital bicuspid aortic stenosis
About 2% of babies are born with aortic stenosis. Even if you have a congenital valve defect, you might not develop symptoms until adulthood. Most people with this condition will eventually require surgery to replace the valve.
Calcific aortic stenosis
Calcific aortic stenosis develops as the valve goes through a disease process similar to atherosclerosis. Lipids such as cholesterol accumulate on the valve, leading to inflammation, and then calcification occurs. These changes slowly progress for about 10-15 years before they harden the valve enough to cause symptoms.
What symptoms are caused by aortic stenosis?
Chances are you’ll learn that you have aortic stenosis long before you have symptoms, because it’s often discovered when your doctor hears a heart murmur during a routine physical examination. A heart murmur doesn’t always mean you have aortic stenosis. Further heart testing such as an echocardiogram or electrocardiogram may be ordered to diagnose the cause of the murmur.
The first signs of aortic stenosis often appear when you engage in physical activities, whether walking up stairs or playing your favorite sport, because your heart will struggle to pump enough blood to keep up when your body demands increased oxygen. When symptoms occur, you may experience:
- Shortness of breath
- Chest pain, pressure or tightness
- Fainting or dizziness
- Heart palpitations or pounding
- Fatigue
How is aortic stenosis treated?
Medical treatment may relieve some symptoms caused by aortic stenosis and also deal with coexisting cardiovascular issues such as high blood pressure. The only treatment for aortic stenosis, however, is surgery to replace the aortic valve.
Balloon valvuloplasty is a procedure that temporarily opens the valve. In adults, the valve eventually narrows again, so valvuloplasty is usually done if they may not be healthy enough for surgery.
If you need a valve replacement, your surgery may be performed using conventional open heart surgery or a less invasive procedure called transcatheter aortic valve replacement (TAVR). During TAVR, the valve is placed in a catheter, then guided through blood vessels to the aortic valve, where the new valve is implanted.