Aortic Valve Stenosis

The aortic valve is located in the heart (between the left ventricle and aorta) and is responsible for allowing blood to flow from the left ventricle into the aorta. The aortic valve contains three leaflets, and should these leaflets become abnormally rigid (a condition known as aortic stenosis) they do not open fully – which causes the valve to narrow, making it harder for blood to move from the heart to the rest of the body. 

Aortic stenosis is most commonly caused by calcium buildup on the leaflets of the aortic valve – which tends to occur as people get older. The other cause stems from birth defects during which two leaflets are fused into one – meaning the “tricuspid” aortic valve becomes a “bicuspid” aortic valve. 

Mitral valve regurgitation can be the result of several things, including: 
  • Mitral valve prolapse (mitral valve does not close properly) 
  • Damaged tissue 
  • Congenital defects 
  • A prior heart attack 
  • Rheumatic fever 
  • Endocarditis (inflammation of the heart valves)

Causes of Aortic Valve Stenosis

There are several major causes of aortic stenosis:
  • Calcification buildup over many years
  • Congenital malformation (e.g., “bicuspid” aortic valve)
  • Rheumatic fever in childhood
  • Damage caused by prior bacterial infection 

Symptoms

Symptoms stemming from aortic stenosis generally manifest after the stenosis becomes quite severe and often gradually develop over a significant period of time. 

They may include one or more of the following:
  • Chest pain (angina)
  • Shortness of breath (dyspnea), particularly when exerting yourself
  • Feeling faint (presyncope) or actually losing consciousness (syncope)
  • Fatigue during times of increased activity

Risk Factors

Risk factors for developing aortic valve stenosis include one or more of the following:

  • Biscupid aortic valve: Normally, the aortic valve consists of three leaflets. In some patients, however, the aortic valve consists of only two leaflets and is called a bicuspid. It is generally thought that the turbulence of blood flowing across this valvular malformation accelerates the development of aortic stenosis. Patients who have a bicuspid aortic valve that becomes severely stenotic often present for surgery in their 50s.
  • Advanced age: Aortic valve stenosis has been linked to increasing age and the buildup of calcium deposits on the aortic valve over time. This is often termed senile calcific aortic stenosis.
  • Rheumatic fever: Individuals who developed rheumatic fever during childhood have a greater chance of developing aortic valve stenosis later in life, presumably due to immunologic damage to the valve leaflets early in life.

Diagnostic Tests

Tests used for diagnosing aortic valve stenosis include an electrocardiogram (ECG), chest X-ray, echocardiogram, and cardiac catheterization.

Electrocardiogram (ECG): An ECG measures the electrical impulses of the heart. Abnormal electrical conduction patterns indicating thickening of the left ventricular muscle can be a sign of significant aortic stenosis. The extra work that the heart must exert to force blood across a stenotic aortic valve leads to thickening of the ventricular muscle.

Chest X-ray: A chest X-ray can reveal calcium deposits that have built up on a stenotic aortic valve and can show a left ventricle that has enlarged in response to significant aortic stenosis.

Echocardiogram: Echocardiography provides excellent functional images of the heart, including all four of its valves. It is the primary imaging study used to diagnose aortic valve disease, including stenosis.

Cardiac catheterization: A cardiac catheterization, or coronary angiogram, is performed by threading a thin catheter into the heart via an artery in your leg or arm and injecting dye directly into the coronary arteries. These studies map out the coronary anatomy and detect narrowing within the arteries. For patients with aortic stenosis, this study is used to either rule out significant coronary artery disease or to help confirm a diagnosis of aortic stenosis in equivocal cases by directly measuring the pressure across the aortic valve.


Treatment

Aortic valve replacement: Severe aortic stenosis is almost always treated with aortic valve replacement surgery in which the diseased native valve is removed and replaced with a prosthetic valve. Our internationally renowned cardiac surgeons at Yale have integrated the most innovative techniques into their practice and are experts at aortic valve replacement. In appropriate patients, we offer minimally invasive techniques, which allow our patients to experience reduced recovery times and less postoperative discomfort.

Balloon valvuloplasty (valvotomy): This is a non-surgical procedure designed to crack open and dilate a stenotic aortic valve. A balloon valvuloplasty is more commonly performed in infants and children because it tends to be less successful with adults. A surgical balloon is attached to the tip of a thin catheter, which is gently guided through the artery in the arm or groin to the heart and across the aortic valve. The balloon is then inflated to open the narrowed aortic valve and reduce the degree of narrowing. The balloon is then deflated and removed through the same artery. In adults, this technique is generally reserved for patients who present excessive risk for open heart surgery

Transcatheter aortic valve implantation (TAVI): In this new procedure, a prosthetic valve is mounted on a catheter that is gently inserted through the femoral artery in the leg and threaded across the native aortic valve. The prosthetic valve is then deployed and displaces the native aortic valve leaflets out of the way. In the United States, two of these devices are in various phases of clinical trials, meaning that patients need to be accepted into the trials based on defined criteria. Yale is the only cardiac center in Connecticut/New England that offers both of these devices to appropriate patients.

We understand that the thought of undergoing any heart surgery can feel overwhelming. Our surgeons will review your surgical plan with you in detail, so that you will know what to expect before, during, and after your operation. You can rest assured that you will be cared for by top surgeons, internationally renowned for their surgical technique and clinical judgment.