Treatment - Aortic Stenosis

Goals of treatment :
- to allow the heart to get more blood into general circulation, improving overall blood supply to the body and the heart.
- to help reduce the person's symptoms.
- to treat complications

Patients with mild aortic stenosis (valve area > 1.2 square centimeters) :
- do not require treatment or restriction of activity

Patients with moderate aortic stenosis (valve area 1.5 to 1.0 square centimeters)
-avoid strenuous activities such as weight lifting or sprinting.

Symptomatic patients (chest pain, syncope, or shortness of breath)
- Aortic Valve replacement surgery
- Balloon valvuloplasty

Aortic Valve replacement : - 2 types of valves :
~ Bioprostheses - processed from pigs (porcine) or cows (bovine)
>less durable than mechanical prostheses
>have the advantage of not needing life-long blood thinning (anticoagulation)
medication to prevent blood clots from forming on the valve surfaces.
>average life expectancy : 10 to 15 years
>rapidly calcify, degenerate and narrow in young patients
>primarily used in patients over 75 years old or in patients who cannot take
blood thinners.
~ Mechanical prostheses
>extremely durable
>life expectancy : from 20 to 40 years.
>require life-long anticoagulation with blood thinners such as warfarin
(Coumadin) to prevent clot formation on the valve surfaces.
>Otherwise, blood clots dislodged from these valves can travel to the brain and
cause embolic stroke or embolic problems in other parts of the body

The surgeon will begin by exposing the heart. An incision is made to divide the breastbone. After the heart is exposed, blood must be rerouted to a heart-lung machine. This allows the blood to be pumped and oxygenated while the surgeon operates on the heart.

Your surgeon can now replace the damaged valve. An incision is made in the aorta to access the aortic valve. The diseased valve leaflets are then removed. After the appropriate valve is selected, sutures are used to secure the prosthetic valve. The aorta is then closed.

Blood is allowed to flow into the coronary arteries. If needed, an electric shock is used to start the heart. Before the chest is closed, pacing wires may be left to control irregular rhythm.

Balloon Valvuloplasty : -The aortic valve area can be opened or enlarged with a balloon catheter (balloon valvuloplasty)
-Patients with critical aortic stenosis can therefore experience temporary improvement with this procedure.
-Most of these valves narrow over a six to 18 month period.
-useful as a short-term measure to temporarily relieve symptoms in patients who are not candidates for aortic valve replacement.
-useful as a bridge to aortic valve replacement in the elderly patient with poorly functioning ventricular muscle.

In balloon valvuloplasty, a thin tube (catheter) with a small deflated balloon at its tip (balloon-tipped catheter) is inserted through the skin in the groin area into a blood vessel, and then is threaded up to the opening of the narrowed heart valve. The balloon is inflated to stretch the valve open and relieve the valve obstruction.

The procedure, which takes up to four hours, is performed in a cardiac catheterization laboratory that has a special x-ray machine and an x-ray monitor that looks like a regular TV screen. The patient will be placed on an x-ray table and covered with a sterile sheet. An area on the inside of the upper leg will be washed and treated with an antibacterial solution to prepare for the insertion of a catheter. The patient is given local anesthesia to numb the insertion site and will usually remain awake, able to watch the procedure on the monitor. After the insertion site is prepared and anesthetized, the cardiologist inserts a catheter into the appropriate blood vessel, then passes the smaller balloon-tipped catheter through the first catheter. Guided by the xray monitor that allows visualization of the catheter in the blood vessel, the physician slowly threads the catheter up into the coronary artery to the heart. The deflated balloon is carefully positioned in the opening of the valve that is being treated, and then is inflated repeatedly, which applies pressure to dilate the valve. The inflated balloon widens the valve opening by splitting the valve leaflets apart. Once the valve is widened, the balloon-tipped catheter is removed. The other catheter remains in place for six to 12hours because, in some cases, the procedure must be repeated. A double-balloon valvuloplasty procedure is often performed on certain high-risk patients because it is considered more effective in restoring blood flow.

Antibiotics :
Since valve infection (endocarditis) is a serious complication of aortic stenosis, these patients are usually given antibiotics prior to any procedure in which bacteria may be introduced into the bloodstream.

This includes routine dental work, minor surgery, and procedures that may traumatize body tissues such as colonoscopy and gynecologic or urologic examinations.

Examples :-oral amoxicillin (Amoxil) and erythromycin (E-Mycin, Eryc, PCE
-intramuscular or intravenous ampicillin (Unasyn), gentamicin (Garamycin), and vancomycin (Lyphocin, Vancocin