What is aortic stenosis?

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Understanding Aortic Stenosis: A Patient Guide

What Is Aortic Stenosis?

Aortic stenosis is a narrowing of your aortic valve—the main valve that controls blood flow from your heart's pumping chamber to the rest of your body. 1 When this valve becomes narrowed, your heart must work much harder to pump blood through the smaller opening, which can eventually lead to serious problems if left untreated. 2

What Causes This Condition?

The most common cause in adults is calcification—a buildup of calcium deposits on the valve leaflets that makes them stiff and unable to open fully. 1 This is essentially a wear-and-tear process that becomes more common as we age, affecting about 3% of people over 65 years old. 3

Other causes include:

  • Bicuspid aortic valve: A congenital condition where you're born with only two valve leaflets instead of the normal three, which tends to wear out earlier in life 1
  • Rheumatic heart disease: Damage from childhood rheumatic fever, though this is now rare in developed countries 1

How Does It Affect Your Heart?

As the valve narrows, two important things happen:

  1. Your heart muscle thickens (left ventricular hypertrophy) to generate more force to push blood through the narrowed valve 2
  2. Your heart's pumping chamber becomes stiffer, making it harder for your heart to fill with blood between beats 2

Initially, these changes help your heart compensate, but over time they can lead to heart failure if the valve isn't replaced. 3

What Symptoms Should You Watch For?

Many people have no symptoms for years while the stenosis is mild or moderate. 3 However, once symptoms develop, they are serious warning signs that require prompt attention:

  • Chest pain or pressure (angina), especially with exertion 4
  • Shortness of breath, particularly during activity or when lying flat 4
  • Dizziness or fainting (syncope), especially with exertion 4
  • Fatigue and reduced ability to exercise 3

If you develop any of these symptoms, you must report them to your doctor immediately, as survival without treatment averages only 2-3 years once symptoms appear. 3

How Is It Diagnosed?

Your doctor will use echocardiography (ultrasound of the heart) as the primary test to diagnose and measure the severity of your aortic stenosis. 1 This test measures:

  • How fast blood flows through the valve (velocity ≥4.0 m/s indicates severe stenosis) 5
  • The pressure difference across the valve (mean gradient ≥40 mmHg indicates severe stenosis) 5
  • The valve opening area (area <1.0 cm² indicates severe stenosis) 5

Additional tests may include CT scans to measure calcium buildup on the valve, with sex-specific thresholds (≥2000 units in men, ≥1200 units in women suggesting severe disease). 6

What About Treatment?

There is currently no medication that can reverse or stop the progression of aortic stenosis. 2 The definitive treatment is valve replacement, either through:

  • Surgical valve replacement (open-heart surgery) 7
  • Transcatheter aortic valve replacement (TAVR): A less invasive procedure where a new valve is inserted through a catheter 1

The timing of valve replacement is critical. If you have severe stenosis with symptoms, valve replacement is strongly recommended and can restore a normal lifespan. 3, 8 For asymptomatic patients, careful monitoring with regular echocardiograms is essential—annually for severe disease, every 1-2 years for moderate disease, and every 3-5 years for mild disease. 3

Important Lifestyle Considerations

  • Avoid strenuous or competitive sports if you have moderate-to-severe stenosis 1
  • Report any new symptoms immediately to your doctor, as this changes management 3
  • Maintain regular follow-up appointments and echocardiograms as recommended 1
  • Manage other heart conditions carefully, including high blood pressure, atrial fibrillation, and coronary artery disease 3

The Bottom Line

Aortic stenosis is a progressive condition that requires careful monitoring. While it may not cause symptoms initially, once symptoms develop, valve replacement becomes necessary and life-saving. Your most important role is to attend regular follow-up appointments and immediately report any new symptoms of chest pain, shortness of breath, or dizziness to your healthcare team. 3

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Calcific aortic stenosis: a disease of the valve and the myocardium.

Journal of the American College of Cardiology, 2012

Research

Aortic stenosis: diagnosis and treatment.

American family physician, 2008

Guideline

Classification and Diagnosis of Severe Aortic Stenosis

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2026

Guideline

CT-Based Severity Classification of Aortic Stenosis

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2026

Guideline

Aortic Stenosis Management

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2026

Research

Aortic stenosis.

Lancet (London, England), 2009

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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