(a) What are the heart valves?
There are four sets of valves in every human heart. These are the aortic valve that connects the left ventricle to the aorta, the pulmonary valve that connects the right ventricle to the pulmonary artery, the mitral valve that connects the left atrium to the left ventricle, and the tricuspid valve that connects the right atrium to the right ventricle. They all act as one-way valves so that blood can only flow from one direction to the other without backflow. Each valve is composed of two to three leaflets, which are thin, smooth, and flexible when normal.
(b) What is heart valve disease?
Valve disease is a condition in which mechanical obstruction of blood flow is the main cause of valve malformation or deformation due to congenital or acquired causes. Acquired, especially rheumatic, heart valve disease is common, and the changes in the valve itself are more obvious. For example, valve thickening, calcification, or further development of scarring can lead to valve deformation, stenosis, or incomplete closure, resulting in loss of normal valve function. This results in abnormal hemodynamic lesions such as blood flow failure or regurgitation, and heart valve disease. If the valve is deformed and the blood flow is not smooth, it is called valve stenosis, such as mitral stenosis, aortic stenosis, etc. If the valve is not closed tightly and the blood flow is regurgitated, it is called incomplete closure. In simple terms, the heart valve is the door, valve stenosis is equivalent to the door can not be opened, valve closure is equivalent to the door can not close.
(C) Why do some patients need valve replacement?
If the normal heart valves are invaded by rheumatic fever or bacteria, resulting in deformation, thickening, adhesion, calcification, or due to trauma or congenital malformation, etc., so that a group or two groups of valves become stenosed or incomplete, and lose the role of one-way valve, and the valve lesion cannot be effectively treated by closed dilatation or shaping, then the original diseased valve must be surgically removed under extracorporeal circulation and replaced by an artificial heart valve. In this case, the original diseased valve must be surgically removed under extracorporeal circulation and replaced with an artificial heart valve to restore the physiological function of the one-way valve and to relieve or alleviate symptoms. Thousands of patients around the world have been rehabilitated by this procedure every year. It has been more than 30 years since the first valve replacement surgery in China. The clinical results are positive.
(D) How many types of artificial valves are available? Which is the best valve to replace?
Artificial heart valves are divided into two main categories. One is the mechanical valve, and the other is the biological valve. The former is made of advanced synthetic materials, while the latter is made of both synthetic advanced materials and complex chemically treated biological tissue membrane surfaces. Each has its own characteristics and advantages and disadvantages. The advantage of a mechanical flap is its durability, while the disadvantage is that it requires lifelong anticoagulation and has a higher rate of thromboembolism. As for the type of flap you are suitable for, your doctor will make a choice based on your requirements and condition.
(E) Why should I use anticoagulation for valve replacement patients?
Because the artificial valve (biological valve or mechanical valve) is not the body’s own group, blood is easy to clot in and around the artificial valve, causing thrombosis and affecting the function of the artificial valve, and if the thrombus is dislodged, it can also cause vascular embolism (brain embolism, lower limb artery embolism, etc.), which is very harmful to people. Therefore, anticoagulation therapy is required for all valve replacement patients to prevent thrombosis. Those with biological valves generally need anticoagulation for only three months after surgery, and those with atrial fibrillation need anticoagulation for six months; while those with mechanical valves need lifelong anticoagulation.
(f) How to anticoagulate patients with valve replacement? What are the anticoagulation criteria?
The main method of anticoagulation is oral anticoagulation tablets. Commonly used anticoagulants include Warfarin tablets. Oral anticoagulation tablets are usually started after the chest drain is removed after surgery or 48 hours after surgery. In order not to overdose or underdose the anticoagulant, blood is drawn periodically after surgery to check the prothrombin time (PT) and the international normalized ratio (INR). This test can reflect the effect of the amount of medication on the coagulation effect, where PT is around 18-24 seconds and INR is 2.0-3.0.
(g) What should I do if my female patient has excessive anticoagulation?
Generally speaking, anticoagulation therapy has little effect on menstruation. Even if menstruation is slightly more or longer than before, there is no need to deal with it as long as it is not serious. If the menstrual flow increases significantly, the amount of anticoagulants can be reduced during menstruation and resumed after menstruation. If menstrual disorders and bleeding continue after anticoagulation therapy, you should visit a gynecologist and take menstrual regulating drugs to stop bleeding. In addition, women of childbearing age should pay attention to contraception during anticoagulation therapy to avoid the risk of increased bleeding from abortion.
(H) Early precautions after flap replacement surgery
The first three months after surgery is an important stage to overcome the surgical trauma and recover the body, the following should be noted.
(1) Continue to take various medications prescribed by the doctor on time, commonly used drugs include anticoagulants, cardiac diuretics, anti-arrhythmics, etc.
(2) Learn to adjust the dose of anticoagulant drugs by yourself. Due to individual differences, each patient requires a different dose of anticoagulants. The doctor has initially figured out the patient’s anticoagulant dose at the time of discharge, and should conduct regular laboratory tests after discharge to further adjust their anticoagulation therapy.
(3) Prevent infections, especially respiratory inflammation, periodontitis, skin boils, and urinary tract infections. They should be controlled as soon as they are detected. Intermittent or persistent fever of unknown origin should not be treated indiscriminately with antimicrobials. You should seek medical attention promptly. To avoid delaying treatment.
(4) Appropriate activity should be maintained after surgery in order to enhance physical fitness and improve quality of life while recovering from cardiac function. The amount of activity should be measured and gradual, so as not to cause shortness of breath. Do not spend the whole day in bed to rest.
(5) Arrange your early recuperation life, keep your spirit happy, relaxed, optimistic and confident.
(6) Do not avoid eating, pay attention to increase nutrition, supplement protein and vitamins. It is not advisable to eat too salty food. Patients with poor heart function should limit the amount of water they drink, and should not eat a lot of thin rice and soups, so as not to increase the burden on the heart with too much liquid.
(7) A detailed examination (including physical examination, electrocardiogram, chest X-ray, echocardiogram, etc.) should be conducted at the hospital three months after surgery, and medication should be adjusted according to the examination results, and health guidance for future life and work should be made.
(ix) Common anticoagulant drugs
The drugs that can be used for anticoagulation after valve replacement are: warfarin, new anticoagulation tablets, heparin. Aspirin can also be used as an adjuvant anticoagulant. The most commonly used is the oral formulation of warfarin. Because of the long half-life of warfarin, if secondary surgery or other procedures other than cardiac surgery are required, heparin may be temporarily substituted by intravenous or subcutaneous injection during discontinuation of warfarin. Warfarin usage is once daily and the daily dosing time can be fixed at 8:00 p.m. Always remember to take the medication on time every day.
(X) Adjustment of anticoagulant dose
Due to individual differences, the amount of anticoagulants used after flap replacement varies from person to person. Some people need 7 mg of warfarin daily, while others need only 0.5 mg. However, most patients use about 3 mg of warfarin per day. Warfarin dosage is relatively stable for each individual, with some fluctuations observed over time, but the range of fluctuation is not significant. Each patient should figure out his or her anticoagulant dose as soon as possible and have regular lab tests to adjust it appropriately. After discharge from the hospital, the patient should be given the initial dose of anticoagulation, and the patient should be tested every 3-5 days and learn to adjust the dosage according to the anticoagulation standards. -After the anticoagulation is more stable (about one month), the test can be done once a week. Anticoagulation therapy after valve replacement is very important and is arguably the key to ensuring good valve function. Patients must pay attention to it and learn to read the labs as soon as possible and adjust their own medications with reference to anticoagulation criteria to improve their quality of life. Anticoagulation therapy is not difficult and should not be seen as a burden by the patient, but rather as a meal that is essential to their daily life. If anticoagulation therapy is in doubt, especially in the first 1-2 months after discharge, if you are not sure how to adjust anticoagulation medication, you should consult your doctor promptly.
(k) What should I do if I need to have a tooth extraction or other surgery after flap replacement?
The best time to have a tooth extraction or other surgery after valve replacement is when your heart function is in good condition. If you are on long-term anticoagulation, you should suspend anticoagulation for two days prior to surgery to prevent postoperative bleeding, or for emergency surgery, special hemostasis and anti-bleeding treatment is required. The surgeon will carefully stop the bleeding during the procedure, and anticoagulation can be continued 24 to 48 hours after the procedure when there is no blood leakage.
(xii) What should I do if I have an arrhythmia after valve replacement?
When you feel an irregular heartbeat, you should go to the hospital to find out the type of arrhythmia. Atrial premature beats are less likely to affect cardiac function and can be corrected with adequate rest and digitalis preparations. Ventricular premature beats should be controlled as early as possible. Measures include rest, potassium supplementation, injection of lidocaine, and the administration of slow-rhythm drugs, but always under the guidance of a doctor. Temporarily discontinue digoxin in case of bradycardia (heart rate less than 60 beats/min) and gradually resume digoxin application after the heart rate is accelerated (greater than 70 beats/min). If the heart rate is still slow after stopping digoxin and there is dizziness, palpitations and other discomfort, promptly seek medical advice. Heart valve disease is often associated with atrial fibrillation. Atrial fibrillation is still present 3 months after surgery, and defibrillation can be performed in the hospital when cardiac function recovers better. If atrial fibrillation is recalcitrant, has a long history, defibrillation is unsuccessful or acute patients do not have to be reluctantly defibrillated to avoid danger. Anticoagulation therapy can be performed along with digitalis preparations to control the heart rate from being too fast or not too slow.
(XIII) Is it normal to have a heart murmur after valve replacement?
A metallic sound similar to that of a clock can sometimes be heard after mechanical valve replacement, which is normal and not a concern. Because the caliber of the prosthetic valve is smaller than that of a normal human valve, a mild systolic or diastolic murmur can sometimes be heard in the precordial region after valve replacement (especially after aortic valve replacement), and if the echocardiogram shows no perivalvular leakage, good valve activity, and good recovery of cardiac function, this murmur has no effect on hemodynamics and is not a cause for concern. If the murmur changes, or if a new murmur develops with palpitations and shortness of breath, prompt medical attention should be sought to analyze the cause.
Immediate medical review should be sought in the following cases.
1.When there is infection in any part of the body.
2. When there is unexplained fever.
3. When there is obvious panic and shortness of breath with swelling.
4. Coughing up foamy blood sputum.
5.When there is jaundice in the sclera and skin of the whole body.
6.When there is bleeding tendency such as subcutaneous bleeding and hematuria.
7.When new heart arrhythmia occurs.
8.When sudden syncope, hemiparesis or pain, chill and pallor of lower limbs occur.