Aortic Valve Surgery: Repair and Replacement

What is the treatment for aortic stenosis?

When heart valves are severely malformed or destroyed, there is no medicine to reverse or mend the damage. In most cases, surgery on the malfunctioning valve can help alleviate symptoms.

Specific treatment for aortic stenosis will be determined in consultation with a cardiologist and cardiac surgery expert in valve disease based on:

your overall health and medical history
extent of the disease
your signs and symptoms
your tolerance for specific medications, procedures, or therapies
expectations for the course of the disease
your opinion or preference

For patients with less advanced disease, follow-up echocardiography is recommended as follows, for patients with:

severe AS: yearly
moderate AS: every 3 years
mild AS: every 5 years

In advanced stages, surgery is required to correct this problem. There is no medical treatment to reverse aortic stenosis. Surgical treatment is indicated in

Patient with severe AS and symptoms or those undergoing other cardiac surgery
Patients with severe AS with heart dysfunction, defined by an ejection fraction < 50%
Patients with severe or moderate AS undergoing cardiac surgery for coronary or other valvular heart disease.

Heart valve replacement: When heart valves are severely malformed or destroyed, they may need to be replaced with a new mechanism. Replacement valve mechanisms fall into two categories: tissue (biologic) valves, which include animal valves and donated human aortic valves, and mechanical valves:

Mechanical valves are made of metal, plastic, or another artificial material and thus have greater durability. The downside is that it requires the patient to remain on anticoagulation for the rest of their life. They are traditionally recommended for patients:

< 60 years old
patients who want to avoid reoperation
patients are already on long-term anticoagulation for another reason

Tissue valves do not require long-term anticoagulation, but they are less durable. They are traditionally recommended for patients:

> 60 years old
patients who prefer to avoid anticoagulation for lifestyles reasons (eg extremely active lifestyle, recent GI bleed, childbearing age)

However durability of a tissue valve is age dependent, due to greater hemodynamic demands in younger. Structural valve deterioration in patients at 10 years:

0-40yo: 40%
40-69yo: 30%
>70yo: 10%

What is transcatheter aortic valve replacement (TAVR)?

Percutaneous and catheter based procedures are available for patients who are not candidates for surgical replacement.

Transcatheter aortic valve implantation (TAVI) is also know as Transcatheter aortic valve replacement (TAVR). Using an approach similar to the approach used for cardiac catheterization of the coronary arteries, TAVI involves a puncture though the skin into the blood vessels in the groin. A catheter, about as wide as a pencil, is then threaded up through vessels in the leg into the aorta then into the heart. A special valve is compressed and inserted into position though the tip of this thin catheter. This approach avoids the need for opening the chest or using a heart lung machine.

Candidates for this percutaneous procedure include patients with severe symptomatic aortic stenosis and are deemed inoperable by a heart surgeon. "Inoperability" has no single definition but most commonly it is defined as a patient who faces more than a 50% risk of death or severe morbidity following a standard, surgical aortic valve replacement. Candidates typically have one or more of the following characteristics: advanced age, previous heart surgery, severe COPD, severe diabetes, home oxygen dependence, pulmonary hypertension, previous radiation to the chest, a severely calcified aorta (aka a porcelain aorta), and/or extreme frailty.

The New England Journal of Medicine recently reported that, in patients with severe symptomatic aortic stenosis who are not candidates for surgery, TAVI (aka TAVR) is associated significantly improved survival, improved symptoms, and improved quality of life compared to standard treatment. In fact, patients undergoing TAVI were nearly twice as likely to be alive at 1 year compared with those who did not.