Cochin Cardiac Club

Health Blog by Dr.Uday Nair

MITRAL VALVE REPAIR AND REPLACEMENT SURGERY



Blood that flows between different chambers of your heart must flow through a valve. This valve is called the mitral valve. It opens up enough so blood can flow from one chamber of your heart (left atria) to the next chamber (left ventricle). It then closes, keeping blood from flowing backwards



The information provided below is about mitral valve replacement surgery resulting from mitral valve regurgitation, mitral valve prolapse, mitral valve stenosis and other heart valve disorders (including infection)
Mitral valve replacement is a complex surgical procedure designed to remove a diseased mitral valve from the heart. There are several different surgical approaches and options for patients to consider


Why do mitral valves need to be replaced?


Heart valves perform the important function of ensuring blood flow in the correct direction throughout the body. The mitral valve directs the flow of blood from the left atrium into the left ventricle, and the aortic valve allows blood to pass from the left ventricle into the aorta.
Mitral valve replacement typically results from two conditions known as stenosis and regurgitation. 



 Mitral valve stenosis


Mitral valve stenosis diagnosis suggests that the patient's valve fails to open properly due to stiff or rigid valve leaflets. Mitral stenosis can be caused from infection, calcification of the heart valve leaflets or tissue degeneration due to age.

Because a stenotic mitral valve may cause blood to back up into the lungs, careful monitoring of mitral valve stenosis symptoms should be monitored. Severely stenotic mitral valves may require mitral valve replacement surgery.

 Mitral valve regurgitation



Mitral Valve Repair and Replacement Surgery





Mitral valve replacement may also be required for patients suffering from mitral valve regurgitation also known as mitral insufficiency. When the mitral valve fails to close properly (primarily due to mitral valve prolapse), the need for mitral valve replacement is usually determined by (i) how severely the symptoms impact the patient and (ii) how well those symptoms can be controlled by medical treatment.
However, it should be noted that many patients who are asymptomatic may require mitral valve replacement surgery if their heart is dilated (enlarged) or experiencing other issues related to heart valve disease and/or congestive heart failure.

An operation to repair or replace a mitral valve takes 2-3 hours to perform. The damaged valve is either repaired and supported with a "ring" or it is replaced with either a "tissue" or "mechanical" valve . Although tissue and mechanical valves function similarly, there are distinct advantages and disadvantages of each. The advantage of mechanical valves, which are made from ceramic, is that they last forever. The disadvantage of mechanical valves is that they require anticoagulation with blood thinners for the remainder of a patient's life.
The advantage of tissue valves, which are made from cow or pig hearts, is that they do not require formal anticoagulation. The disadvantage of tissue valves, however, is that they generally wear out after 12-15 years, at which time another operation would be required to replace the worn out valve.


Procedure;Mitral Valve Repair/Replacement-open heart surgery




The operation itself requires general anesthesia ... the patient is asleep for the entire course of the operation. The surgeon opens the chest by dividing the breast bone or sternum. Tubes and cannulae are inserted into the heart and major blood vessels surrounding the heart in preparation for cardiopulmonary bypass with the heart-lung machine. At this point, blood is redirected from the heart into the heart-lung machine, the heart is stopped, and the aorta is clamped. This permits the surgeon to safely open and operate on the heart without blood pumping through it. The heart-lung machine continues to pump freshly oxygenated blood to the rest of the body, in effect, taking over the roles of the heart and lungs.
The surgeon then opens the heart, usually through the left atrium, and exposes the mitral valve. If the valve is only partially damaged, it is repaired and the rim or "annulus" of the valve is supported with a "ring". If, however, the valve cannot be repaired, it is removed. Non-absorbable sutures with bolsters or "pledgets" are used to sew the new valve into position . The valve is tested, to ensure that it opens and closes safely, and then the left atrium of the heart is closed. The clamp on the aorta is removed, and all air is evacuated from the heart. As the heart regains its strength, the patient is weaned from the heart-lung machine and the heart and lungs resume their normal functions


Procedure-Minimally invasive mitral valve surgery:

It is done through much smaller incisions (cuts) than the large incision needed for open surgery
Before your surgery you will receive general anesthesia. This will make you unconscious and unable to feel pain.
There are several different ways to perform minimally invasive mitral valve surgery.
  • Your heart surgeon may make a 2-inch to 3-inch-long incision (cut) in the right part of your chest near the sternum (breastbone). Muscles in the area will be divided so your surgeon can reach the heart. A small cut is made in the left side of your heart so the surgeon can repair or replace the mitral valve.
  • In endoscopic surgery, your surgeon makes 1 to 4 small holes in your chest. Then your surgeon uses special instruments and a camera to do the surgery.
  • For robotically-assisted valve surgery, the surgeon makes 2 to 4 tiny cuts (about ½ to ¾ inch) in your chest. The surgeon uses a special computer to control robotic arms during the surgery. The surgeon sees a 3-dimensional view of the heart and aortic valve on the computer. This method is very precise.
You will not need to be on a heart-lung machine for these types of surgery, but your heart rate will be slowed by medicine or a mechanical device.
If your surgeon can repair your aortic valve, you may have:
  • Ring annuloplasty -- The surgeon repairs the ring-like part around the valve by sewing a ring of metal, cloth, or tissue around the valve.
  • Valve repair -- The surgeon trims, shapes, or rebuilds 1 or more of the 3 leaflets of the valve. The leaflets are flaps that open and close the valve.



If your mitral valve is too damaged, you will need a new valve. This is called replacement surgery. Your surgeon will remove your mitral valve and sew a new one into place. There are two main types of new valves:
  • Mechanical -- made of man-made materials, such as cloth, metal, or ceramic. These valves last the longest, but you will need to take blood-thinning medicine, such as warfarin (Coumadin) or aspirin, for the rest of your life.

  • Biological -- made of human or animal tissue. These valves last 12 to 15 years, but you may not need to take blood thinners for life.

The surgery may take 1 to 3 hours.
This surgery can also be done through a groin artery, with no incisions on your chest. The doctor sends a catheter (flexible tube) with a balloon attached on the end. The balloon stretches the opening of the valve. This procedure is called percutaneous valvuloplasty.

Why the Procedure is Performed:


You may need surgery if your mitral valve does not work properly.
  • A mitral valve that does not close all the way will allow blood to leak back into the left atria. This is called mitral regurgitation.
  • A mitral valve that does not open fully will restrict blood flow. This is called mitral stenosis.
Minimally invasive surgery may be done for these reasons:
  • Changes in your mitral valve are causing major heart symptoms, such as angina (chest pain), shortness of breath, syncope (fainting spells), or heart failure.
  • Tests show that the changes in your mitral valve are beginning to seriously affect your heart function.
  • Your heart valve has been damaged by endocarditis (infection of the heart valve).
A minimally invasive procedure has many benefits. There is less pain, blood loss, and risk of infection. You will also recover faster than you would from open heart surgery.


Risks:


Risks for any surgery are:
  • Reactions to medicines
  • Breathing problems
  • Blood clots in the legs that may travel to the lungs
  • Infection, including in the lungs, kidneys, bladder, chest, or heart valves
  • Blood loss
Minimally invasive surgery techniques have far fewer risks than open surgery. Possible risks from minimally invasive valve surgery are:
  • Irregular heartbeat that must be treated with medicines or a pacemaker
  • Damage to other organs, nerves, or bones
  • Heart attack, stroke, or death


Before the Procedure;


Always tell your doctor or nurse:
  • If you are or could be pregnant
  • What drugs you are taking, even drugs, supplements, or herbs you bought without a prescription
You may be able to store blood in the blood bank for transfusions during and after your surgery. Ask your surgeon about how you and your family members can donate blood.
For the 2-week period before surgery, you may be asked to stop taking drugs that make it harder for your blood to clot. These might cause increased bleeding during the surgery.
  • Some of them are aspirin, ibuprofen (Advil, Motrin), and naproxen (Aleve, Naprosyn).
  • If you are taking warfarin (Coumadin) or clopidogrel (Plavix), talk with your surgeon before stopping or changing how you take these drugs.
Prepare your house for when you get home from the hospital.
The day before your surgery. Shower and shampoo well. You may be asked to wash your whole body below your neck with a special soap. Scrub your chest 2 or 3 times with this soap. You also may be asked to take an antibiotic, to guard against infection.

During the days before your surgery:
  • Ask your doctor which drugs you should still take on the day of your surgery.
  • If you smoke, you must stop. Ask your doctor for help.
  • Always let your doctor know if you have a cold, flu, fever, herpes breakout, or any other illness in the time leading up to your surgery.
On the day of the surgery:
  • You will usually be asked not to drink or eat anything after midnight the night before your surgery. This includes chewing gum and using breath mints. Rinse your mouth with water if it feels dry, but be careful not to swallow.
  • Take the drugs your doctor told you to take with a small sip of water.
  • Your doctor or nurse will tell you when to arrive at the hospital.


After the Procedure


Expect to spend 3 to 5 days in the hospital after surgery. You will wake up in the intensive care unit (ICU) and recover there for 1 or 2 days. Nurses will closely watch monitors that show information about your vital signs (pulse, temperature, and breathing).
Two to 3 tubes will be in your chest to drain fluid from around your heart. They are usually removed 1 to 3 days after surgery. You may have a catheter (flexible tube) in your bladder to drain urine. You may also have intravenous (IV, in a vein) lines to get fluids.
You will go from the ICU to a regular hospital room. Your nurses and doctors will continue to monitor your heart and vital signs until you are stable enough to go home. You will receive pain medicine for pain in your chest.
Your nurse will help you slowly resume some activity. You may begin a program to make your heart and body stronger.
A temporary pacemaker may be placed in your heart if your heart rate becomes too slow after surgery

Outlook (Prognosis)


Mechanical heart valves do not fail often. However, blood clots develop on them. If a blood clot forms, you may have a stroke. Bleeding can occur, but this is rare.
Biological valves tend to fail over time. But they have a lower risk of blood clots.
Techniques for minimally invasive heart valve surgery have improved greatly over the past 10 years. These techniques are safe for most patients, and they reduce recovery time and pain.




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