MITRAL VALVULAR SURGERY
The heart is a hollow muscle where four chambers are delimited. Between the upper (atria) and lower (ventricles) chambers are the atrioventricular valves, one on the left side (mitral valve, separates the left atrium from the left ventricle) and another on the right side (tricuspid valve, separates the atrium right ventricle).
Heart valves act as "doors" that open in only one direction and prevent the return of blood when closing, allowing the unidirectional flow of blood with each beat.
TWO MAIN TYPES OF MITRAL VALVE DISEASE:
The most common diseases of the heart valves are the following:
Stenosis , when the valve does not open enough due to calcification, fusion or thickening of the leaflets or leaflets that form it.
Regurgitation or insufficiency , when the valve does not close well and allows the blood to flow in the opposite direction to which it belongs.
In both cases, if the disease is severe, there are symptoms (fatigue, shortness of breath, swelling or edema in the legs, etc.) or impairment of the function of the heart, surgical intervention is necessary, which implies repair or replacement with a prosthesis. biological (from bovine or porcine tissue) or mechanical (composed of pyrolytic carbon and dacron).
What is valve repair?
When the affected valve can be repaired, this is the best option since we retain the patient's native valve. We can also avoid the use of postoperative anticoagulant medication (Sintrom®). It can be performed in sparsely affected rheumatic valves, mitral regurgitation with preferentially posterior leaflet involvement, or aortic regurgitation with anatomical characteristics favorable for repair.
The following are some of the surgical procedures that can be performed to repair a valve:
Commissurotomy , consists of making a cut on the commissures (where the leaflets or veils join) fused by the disease.
Annuloplasty , consists of placing a prosthetic ring around the valve ring to give consistency to it and avoid its dilation, restoring the geometry that enables the valve to function properly.
Quadrangular / triangular resection , consists of resecting a part of the valve to re-establish its competence.
Descaling , consists of removing the calcium deposits accumulated in the valves.
Neochord implantation , a technique that consists of “manufacturing” the subvalvular tissue that anchors the valve to the ventricle (tendinous chords) so that the valve closes well.
Patch placement (usually of the patient's own pericardium) to close small defects in the leaflets or leaflets that cause valve insufficiency.
What is valve replacement?
If the valve cannot be repaired, it must be replaced. In the case of coexisting disease in several of the valves, it may be necessary to change more than one valve.
There are two types of valves that are used in valve replacement:
Mechanical valves , made of pyrolytic carbon (a very durable material and to which blood cells or germs tend not to adhere) and dacron (very resistant tissue that covers the valve ring and to which the sutures that join the valve are sewn valve to the heart) which gives them strength and durability. However, to avoid the formation of clots in the mechanical valves, it is necessary to take anticoagulants for life (Sintrom®).
Biological valves , made with bovine or porcine pericardium, or with porcine valves. Biological valves degrade, unlike mechanical ones, requiring replacement when they stop working, which usually occurs between 10 and 20 years after implantation. That is why they are reserved for people over 65 years of age or women who will not be able to take Sintrom® because they want to become pregnant.
You and your doctor will decide which type of valve is best for you.
Valve repairs and replacements are performed with extracorporeal surgery. It is what has commonly been called "open heart surgery".
What is the mitral valve surgery procedure:
Who is in the operating room during the intervention?
During a cardiac intervention, a highly trained group works as a team. The following is a list of the people who are in the operating room during a heart procedure.
The cardiovascular surgeon, who leads the surgical team and performs the intervention.
The assistant cardiovascular surgeons.
The cardiovascular anesthesiologist, who administers the medications that make the patient sleep during the intervention (anesthesia). It ensures that the patient receives the correct amount of drug during surgery and is in charge of controlling the monitors that monitor the patient's condition during the operation.
The perfusionist, who controls the heart-lung machine.
Cardiovascular nurses, who have received specific training to help during a cardiac intervention.
Before the intervention
Except in urgent cases, the intervention will be carried out on a date suitable for you and with the availability of an operating room by the surgeon. You should inform him of your recent health status including if you have had a cold, tooth decay, or fever. Remember to bring the medications you are taking or have taken in recent days to the Hospital. You will probably enter the day before or the morning of the intervention.
You will need to bathe with an antiseptic solution and the area near the surgical field will be shaved. With this we avoid future infections. You will be fasting from midnight before the intervention, in order not to suffer anesthetic complications. For this same reason, it is advisable that in case of smoking, do not do so for at least two weeks prior to the intervention.
After admission, an electrocardiogram, a blood test and a chest X-ray will be performed (if not already done).
As part of your pre-anesthetic medication, you will likely be given a sedative to help you relax before going to the operating room. Once in the operating room, you will be given a route through which to administer anesthetic drugs. You probably do not remember this after the intervention.
During the intervention
Once you are asleep, a series of tubes and probes will be inserted:
Endotracheal tube: allows connection to a respirator during surgery
Nasogastric tube: it is inserted through the nose and reaches the stomach, so that fluids and air do not accumulate and you do not suffer nausea or vomiting when you wake up.
Bladder catheter: it is introduced through the urethra and reaches the urinary bladder, which allows urine to be collected during the intervention, preventing the bladder from filling up and making it possible to know the functioning of the kidneys.
Transesophageal echocardiogram probe: used when we are going to perform a valve repair, it allows us to assess the functioning of the valve before and after the intervention. This tube is removed before leaving the operating room.
During the procedure, you will be given heparin, an anticoagulant that prevents the blood from clotting while you are having surgery. Before ending the intervention, an "antidote" is administered, protamine, which reverses this action.
If the valve surgery is associated with coronary surgery, it may be necessary to remove a piece of a vein in the leg (internal saphenous vein) to be used as a vein graft or an artery that runs through the interior of the chest (mammary artery internal) to be used as an arterial graft.
You will be left between 1 and 3 drainage tubes, which serve to evacuate the normal initial bleeding that occurs after the intervention. Cardiac surgery can lead to increased initial excitability of the heart tissue, so you will be implanted between 1 and 5 epicardial pacemaker electrodes, connected to the heart and protruding from the lower edge of the ribs. These electrodes allow the placement of a temporary pacemaker in case of rhythm disturbances during the initial postoperative period.
The operation can last between 2 and 6 hours on average, depending on the number of valves that need to be repaired or replaced. A longer duration of the intervention does not necessarily imply greater severity.
Initially, you will be admitted to the intensive care unit (ICU) where you will wake up between 3 and 9 hours after the end of the operation. When you are able to breathe on your own, the endotracheal tube will be removed. When the drainage tubes stop draining (generally the next day) they will be removed and after 24-72 hours on average, they will be discharged to the plant, where they will remain between 3 and 7 days on average.
Life after a valve replacement or repair
After this intervention, recovery may take a variable time depending on the initial disease and the state of health that occurred before the operation. In some cases, the reason for the intervention is to prevent a progression of the deterioration of the heart, with which functional improvement can take up to a year to become evident. In others, you will notice rapid relief from symptoms. Ask your surgeon about your specific condition.
You can walk or swim slowly and a cardiac rehabilitation program would be desirable. In some cases, you must keep a relative rest after the intervention.
You will also need to continue taking drugs in some cases. This also depends on the initial disease.
In 4 to 6 weeks you will be able to return to an office job. In case your job requires physical exercise or significant stress, this time may be extended or even require a leave or change of employment in extreme cases.
In exceptional cases, a valve repair may require a second intervention due to failure of the repair (either due to dehiscence of the sutures, ineffectiveness of the first intervention or evolution of the initial disease).
Patients with mechanical valves should take an anticoagulant medication (Acenocoumarol or Sintrom®) to thin the blood and prevent the formation of thrombi that prevent the correct opening of the valve. This drug requires periodic tests (probably at your Health Center) to control the anticoagulation status (INR). A very high INR can lead to bleeding, and a low INR indicates that you are not protected against valve thrombosis. Therefore, it is advisable that you carry a copy of the discharge report where it indicates the ideal INR for you. Present it to any doctor you see, including your dentist and primary care physician. On the other hand, it is very possible that you or those close to you will hear a click in the chest. This is normal and indicates the correct closure of your new valve. If you heard it before and you stop hearing it or if you start with symptoms of valve failure (exhaustion, feeling short of breath, swelling in the legs ...), consult your doctor.
Patients with biological valves should be aware that they may require replacement within 10 to 20 years, so your doctor may recommend that you perform an echocardiogram periodically. Also, if you start with symptoms of valve failure (exhaustion, feeling short of breath, swelling in the legs ...), consult your doctor. Patients with a biological valve do not need to take blood thinners unless instructed to do so by their doctor.
You should take an antibiotic before undergoing any dental or surgical procedure, as during these procedures germs could enter the blood and adhere to the repaired or replaced valve, causing a serious infection of the same, which we call bacterial endocarditis.
Minimally invasive valve surgery
In selected cases, valve surgery can be performed with small incisions, which reduces postoperative pain, hospital stay, and postoperative recovery time. In the case of the mitral valve, this is done with a technique known as "surgery through ports, Heart-Port or Port-Access" where the instruments and the chamber are inserted through small incisions smaller than 2 cm and the valve is repaired or changed. for a somewhat larger work port.
However, not all patients are candidates for this type of surgery. Patients with severe valve damage, disease of more than one valve, concomitant coronary surgery, reoperations, or anatomical problems such as obesity or severe scoliosis, are not susceptible to minimally invasive surgery.