Aortic Valve Stenosis – Symptoms and Causes
Overview
Aortic valve stenosis is a serious heart valve disease where the aortic valve narrows, restricting blood flow from the heart to the body.
This condition becomes more common with age, affecting about 6% of people over 75 years old in the United States.
The aortic valve sits between the left ventricle and the aorta, opening and closing billions of times during a person’s life. When working properly, it opens to 3-5 square centimeters during heart contraction and seals tightly as the heart relaxes.
What Causes Aortic Stenosis?
Aortic stenosis develops through an active inflammatory process with features similar to atherosclerosis. Several risk factors contribute to its development:
- High blood pressure
- Abnormal cholesterol levels
- Diabetes
- Chronic kidney disease
- Genetic predisposition
Most people with normal three-leaflet valves don’t experience significant narrowing until their 70s or 80s. However, those born with abnormal valves face problems earlier:
| Valve Type | Typical Age of Severe Symptoms |
|---|---|
| Normal (3 leaflets) | 70s-80s |
| Bicuspid (2 leaflets) | 50s-60s |
| Unicuspid (1 leaflet) | Even earlier |
Disease Progression
Aortic stenosis typically worsens over time as the valve calcifies and narrows. This creates pressure overload in the heart, causing:
- Heart muscle thickening
- Muscle stiffening
- Reduced pumping efficiency
Early symptoms include:
- Shortness of breath
- Chest discomfort
Advanced symptoms can be life-threatening:
- Congestive heart failure
- Sudden loss of consciousness
- Sudden death in severe cases
Diagnosis
Doctors often suspect aortic stenosis during physical exams, but confirmation requires tests:
Transthoracic Echocardiography (primary diagnostic tool):
- Assesses heart size and function
- Measures valve area and gradient
- Valve area less than 1cmยฒ and mean gradient over 40mm Hg indicates severe stenosis
In certain cases, additional tests help clarify severity:
- Cardiac CT scans
- Cardiac catheterization
Aortic Regurgitation
The other main aortic valve problem is regurgitation (leakage), where blood flows backward into the heart. Unlike stenosis, which creates pressure overload, regurgitation causes volume overload, leading to heart enlargement and thickening.
Causes of aortic regurgitation include:
- Congenital valve abnormalities – unicuspid or bicuspid valves.
- Acquired conditions – previous valve infection (endocarditis).
- Aortic root problems – dilation or aneurysm with a normal valve.
Diagnosis follows a similar path to stenosis, with echocardiography as the main tool. Sometimes transesophageal echocardiography or cardiac MRI provides better information about leakage severity.
Surgery is indicated for severe regurgitation with:
- Symptoms
- Heart dysfunction
- Significant heart enlargement
Treatment Options
Aortic valve disease generally requires surgical intervention, as no effective medications exist. Treatment options include:
Traditional surgery:
- Open heart procedure with full sternotomy
- Valve replacement (most common)
- Valve repair (less common)
Newer approaches:
- Minimally invasive thoracotomies (smaller incisions)
- Transcatheter Aortic Valve Replacement (TAVR)
- Uses catheters inserted through groin arteries
- Avoids open chest surgery
- Eliminates need for cardiopulmonary bypass
Signs and Symptoms
Aortic valve stenosis varies from mild to severe. Many people with this condition may not experience symptoms for years. Symptoms typically appear when the valve becomes very narrow.
Common symptoms of aortic valve stenosis include:
- Chest discomfort that occurs during physical activity
- Dizziness or fainting when exercising
- Breathing difficulties, particularly during exertion
- Tiredness that worsens with increased activity
- Fast or irregular heartbeat
In children with aortic valve stenosis, symptoms may also include:
- Poor appetite
- Difficulty gaining weight
If aortic valve stenosis progresses, it can lead to heart failure. Signs of heart failure include severe fatigue, breathing problems, and swelling in the feet and ankles.
When to Contact a Medical Professional
If you notice an irregular heartbeat or experience any symptoms of aortic valve stenosis, schedule an appointment with your healthcare provider. Early detection and treatment can help manage the condition and prevent complications.
Causes
The aortic valve plays a key role in heart function. When this valve narrows, a condition called aortic valve stenosis develops. This narrowing prevents proper blood flow from the heart to the body.
The heart contains four valves that ensure blood flows correctly: the aortic, mitral, tricuspid, and pulmonary valves. Each valve has flaps (cusps) that open and close during heartbeats.
In aortic valve stenosis, the valve between the left ventricle and the aorta doesn’t open fully.
Several factors can lead to aortic valve stenosis:
Birth defects in the heart structure can cause stenosis. Some people are born with an aortic valve that has only two cusps instead of three (bicuspid aortic valve).
Less commonly, a person might have an aortic valve with one or four cusps.
Calcium buildup is another common cause. As blood flows across the valve, calcium minerals from the blood can collect on the valve surfaces over time. These deposits include:
- Gradual accumulation that increases with age
- More rapid buildup in people with existing valve abnormalities
- Possible symptoms appearing between ages 70-80 for age-related cases
Rheumatic fever effects can damage heart valves. This complication from untreated strep throat can:
- Create scar tissue on the aortic valve
- Narrow the valve opening
- Create rough surfaces where calcium easily collects
When the aortic valve narrows, the heart must work harder to pump blood to the body. This extra strain causes the left ventricle to thicken as it tries to maintain normal blood flow.
Eventually, this overwork can weaken the heart muscle. The impact of aortic valve stenosis varies based on the severity of narrowing and how quickly it progresses.
Some people with mild stenosis may never experience symptoms, while others develop significant heart problems requiring treatment.
Risk Factors
Several factors may increase your chance of developing aortic valve stenosis:
- Age: The risk increases as you get older.
- Congenital Heart Defects: Especially bicuspid aortic valve, where the valve has two flaps instead of three.
- Chronic Kidney Disease: Long-term kidney problems can affect heart valve function.
- Cardiovascular Risk Factors: Diabetes, high cholesterol, and high blood pressure.
- Heart Infections: Including rheumatic fever and infective endocarditis.
- Chest Radiation: Previous radiation therapy to the chest area.
These factors can lead to valve damage and narrowing over time.
Complications
Aortic valve stenosis can lead to several health problems. These include:
- Heart Failure: The heart has to work harder and may weaken over time.
- Stroke: Blood flow issues can affect the brain.
- Blood Clots: These may form and travel through the bloodstream.
- Bleeding: Unusual bleeding can occur in some cases.
- Arrhythmias: Irregular heartbeat patterns may develop.
- Heart Infections: Conditions like endocarditis can affect the heart.
Prevention
Regular health measures can help reduce aortic valve stenosis risks. When experiencing a sore throat, seek medical attention promptly. Untreated strep throat may lead to rheumatic fever, which can damage heart valves.
Children and young adults face higher risks of rheumatic fever, but antibiotics usually treat strep throat effectively.
Heart health maintenance plays a crucial role in prevention. Discuss personal risk factors with healthcare providers and develop strategies to manage conditions like high blood pressure, obesity, and high cholesterol levels.
These conditions may contribute to aortic valve problems over time.
Don’t neglect dental health. Regular brushing, flossing, and dental check-ups help prevent gum disease (gingivitis).
Research suggests a possible connection between infected gums and endocarditis, a heart infection that increases aortic valve stenosis risk.
