Other artificial heart valves are how to have a heart valve

Mechanical valves are made of artificial materials, biological valves made from natural materials, usually from the pig's pericardium or the pericardium.

Heart valve replacement surgery is becoming increasingly popular with heart disease patients. There are many types of materials used to replace valves, of which the most common are mechanical heart valves and biological heart valves. There are also homologous pieces taken from the tissues of the dead. Doctors must consider each advantage and disadvantage in each specific case to explain to patients and families the choice of the most suitable replacement valve.

Advantages and disadvantages of mechanical valves

Mechanical valve.

Thanks to the carbon pyrolytic carbon or titanium artificial material, the biggest advantage of mechanical valves so far is its durability. Theoretically this valve can exist to the patient's lifetime without affecting the structure and function. Mechanical valves cost only half the biology valve.

However, because it is made of artificial materials, the biggest drawback of this valve is that it requires patients to use anticoagulants for life. Anticoagulants often come with many risks. If the patient uses an overdose, may have multiple bleeding such as skin (bruises), gastrointestinal tract (gastrointestinal hemorrhage), urinary tract (blood in the urine) and the most severe is cerebral hemorrhage , can lead to severe disability or death for the patient.

In contrast, taking an anticoagulant inadequate will increase the risk of blood clots on the mechanical valve, affecting valve action. The most severe is causing valve jam and can lead to death if not timely intervention. Or blood clots can burst and follow the arteries that cause infarction of organs, the most dangerous is cerebral infarction.

Anticoagulants also complicate cases of extra-cardiac surgery in patients who have had mechanical valve changes or patients who develop a disease that requires contraindications to anticoagulation such as cerebral hemorrhage, gastrointestinal hemorrhage . Currently Improved mechanical valves can use lower anticoagulant doses, limiting the risk for patients.

Advantages and disadvantages of biological valves

If the mechanical valve is made of artificial material, the bio-valve is made of natural material , usually from the treated heart or the pericardium. Therefore, the biggest advantage is that there is no need to use antifreeze for life . Doctors often stop anticoagulation for patients after 3 months of surgery. This is the time needed for endogenous artificial materials and the risk of blood clots is no longer available.

The biggest disadvantage of bio-valves is that the natural valve tissue heterogeneity will degrade over time , affecting the operation of the valve and will cause re-narrowing, artificial valve opening. So after a period of time, patients often need surgery to replace the new valve.

The degree of valve degradation depends on the age of the patient and the pressure on the valve . The younger the patient, the faster the degenerative valve. In children, 50% of the valves will be damaged after 4 years and 80% after 6 years. In people over 60 years old, 5% of valves will degenerate after 5 years, 20% after 8 years and 30% after 10 years.

Biological valve.

Factors to consider when selecting valves

- Age of patients

The current recommended age limit for bio-valves is over 60. At this age, the rate of degradation of biological valves is much slower than before. However, due to the development of cardiovascular surgery and newer valve generations, the recommended age is still controversial.

- Antifreeze

The patient's attitude towards the use and risk of anticoagulants is important in selecting valves. In patients with contraindications or unable to control the use of drugs such as patients who refuse to cooperate, mental patients, who are from remote areas . should choose bio-valves. Conversely, if the patient has been using long-term anticoagulants due to other pathological conditions, we can choose mechanical valves.

- Infection status

For patients with infectious endocarditis, biological valves or homologous graft are recommended because of the reduced risk of recurrent infections in the postoperative period.

- Risk of thrombosis

The risk of thrombosis includes atrial fibrillation, enlarged left atrium, thrombosis in the left atrium, history of thrombosis . These patients should use mechanical valves because anticoagulation will also be indicated after transparent surgery. life

- Pregnancy

Because of the risk of pregnancy defects in the first 3 months of anticoagulants, the choice of valves for young women who want to become pregnant later should be considered carefully. Biological valves avoid the risk of fetal malformations but the valve will degenerate quickly and must replace new valves sooner. Or the mother is late in pregnancy, when the biological valve has degenerated and aggravated the heart failure condition.

Mechanical valves prevent valve degradation but must discontinue oral anticoagulation for the first 3 months and after 36 weeks, replace with another type of anticoagulant, Heparin, and follow closely. Therefore, it is difficult to apply to remote patients who do not have good medical care.