What is valve replacement?
There are 2 kinds of valves used for valve replacement:
- Mechanical valves, which are usually made from materials such as plastic, carbon, or metal. Mechanical valves are strong, and they last a long time. Because blood tends to stick to mechanical valves and create blood clots, patients with these valves will need to take blood-thinning medicines (called anticoagulants) for the rest of their lives.
- Biological valves, which are made from animal tissue (called a xenograft) or taken from the human tissue of a donated heart (called an allograft or homograft). Sometimes, a patient’s own tissue can be used for valve replacement (called an autograft). Patients with biological valves usually do not need to take blood-thinning medicines. These valves are not as strong as mechanical valves, though, and they may need to be replaced every 10 years or so. Biological valves break down even faster in children and young adults, so these valves are used most often in elderly patients.
I generally recommend Tissue valves for age > 60 years and mechanical valve for age < 50 years. The age group of 50 – 60 years is a gray zone and either choice would not be wrong. More and more younger patients (even in their 40’s) are preferring tissue valves with the aim to avoid anticoagulation (with Warfarin) and its side effects.
During valve repair or replacement surgery, the breastbone is divided, the heart is stopped, and blood is sent through a heart-lung machine. Because the heart or the aorta must be opened, heart valve surgery is open heart surgery.
What to Expect
You may also need a dental checkup and treat any dental infections before a heart valve operation. Dental procedures are the most common cause of infected heart valves and hence must be treated before.
Also, remind your cardiologist and surgeon about all of the medicines you are taking, especially any over-the-counter medicines such as aspirin or those that might contain aspirin. You should make a list of the medicines and bring it with you to the hospital.
It is always best to get complete instructions from your cardiologist and surgeon about the procedure, but here are some basics you can expect when you have valve repair or replacement surgery.
Before the Hospital Stay
The night before surgery, you will be asked to bathe to reduce the amount of germs on your skin. After you are admitted to the hospital, the area to be operated on will be washed, scrubbed with antiseptic, and, if needed, shaved.
A medicine (anesthetic) will make you sleep during the operation. This is called “anesthesia.” Because anesthesia is safest on an empty stomach, you will be asked not to eat or drink after midnight the night before surgery. If you do eat or drink anything after midnight, it is important that you tell your anesthesiologist and surgeon.
If you smoke, you should stop at least 2 weeks before your surgery. Smoking before surgery can lead to problems with blood clotting and breathing.
Day of Surgery
Small metal disks called electrodes will be attached to your chest. These electrodes are connected to an electrocardiogram machine, which will monitor your heart’s rhythm and electrical activity. You will receive a local anesthetic to numb the area where a plastic tube (called a line) will be inserted in an artery in your wrist. An intravenous (IV) line will be inserted in a vein. The IV line will be used to give you the anesthesia before and during the operation.
After you are completely asleep, a tube will be inserted down your windpipe and connected to a machine called a respirator, which will take over your breathing. Another tube will be inserted through your nose and down your throat, into your stomach. This tube will stop liquid and air from collecting in your stomach, so you will not feel sick and bloated when you wake up. A thin tube called a catheter will be inserted into your bladder to collect any urine produced during the operation.
A heart-lung machine is used for all valve repair or replacement surgeries. This will keep oxygen-rich blood flowing through your body while your heart is stopped. A perfusion technologist or blood-flow specialist operates the heart-lung machine. Before you are hooked up to this machine, a blood-thinning medicine called an anticoagulant will be given to prevent your blood from clotting. The surgical team is led by the cardiovascular surgeon and includes other assisting surgeons, an anesthesiologist, and surgical nurses.
After you are hooked up to the heart-lung machine, your heart is stopped and cooled. Next, a cut is made into the heart or aorta, depending on which valve is being repaired or replaced. Once the surgeon has finished the repair or replacement, the heart is then started again, and you are disconnected from the heart-lung machine.
The surgery can take anywhere from 2 to 4 hours or more, depending on the number of valves that need to be repaired or replaced.
Recovery Time
Recovery after valve surgery may take a long time, depending on how healthy you were before the operation. You will have to rest and limit your activities. Your doctor may want you to begin an exercise program or to join a cardiac rehabilitation program.
If you have an office job, you can usually go back to work in 4 to 6 weeks. Those who have more physically demanding jobs may need to wait longer.
Life After Valve Replacement
Patients with a biological valve may need to have the valve replaced in 10 to 15 years. Mechanical valves may also fail, so patients should alert their doctor if they are having any symptoms of valve failure.
Patients with a mechanical valve will need to take a blood-thinning medicine for the rest of their lives. Because these medicines increase the risk of bleeding within the body, you should always wear a medical alert bracelet and tell your doctor or dentist that you are taking a blood-thinning medicine.
Even if you are not taking a blood-thinning medicine, you must always tell your doctor and dentist that you have had valve surgery. If you are having a surgical or dental procedure, you should take an antibiotic before the procedure. Bacteria can enter the bloodstream during these procedures. If bacteria get into a repaired or artificial valve, it can lead to a serious condition called bacterial endocarditis. Antibiotics can prevent bacterial endocarditis.
Patients with mechanical valves say they sometimes hear a quiet clicking sound in their chest. This is just the sound of the new valve opening and closing, and it is nothing to be worried about. In fact, it is a sign that the new valve is working the way it should.
Minimally Invasive Valve Surgery
Minimally invasive valve surgery can only be done in certain patients. This type of surgery cannot be done in patients
- With severe valve damage
- Who need more than one valve repaired or replaced
- Who have clogged arteries (atherosclerosis)
- Who are obese