A mechanical heart valve is a medical device which is implanted in someone's heart to replace a damaged valve such as the mitral valve. The mechanical heart valve maintains the flow of blood in the heart, ensuring that blood moves between the chambers of the heart without allowing it to flow backward and impair heart function. These devices are implanted by surgeons who specialize in heart surgery, in a controlled operating room with a support staff which monitors the patient and assists the surgeon throughout the surgery.
There are a number of reasons why a heart valve may become damaged. Congenital disabilities and illness are two things which can cause heart valves to operate less efficiently. They may leak or they may allow blood to back up in the heart. In both cases, the damaged valve can be diagnosed with the assistance of auscultation of the heart, medical imaging studies to look at the heart, and imaging studies such as Doppler ultrasound to follow the movement of blood through the heart.
When a valve needs to be replaced, patients have several options. A biological artificial valve made from pig or cow tissue can used, a cadaver valve can be implanted, or a mechanical heart valve made from metal can be installed. These valves come in several different designs including bileaflet valves, caged balls, and tilting discs. The valve can last for an extended period of time, unlike biological valves, which will need to be replaced as they wear out.
The prolonged life of the mechanical heart valve is a distinct advantage because it will reduce the need for future surgeries. However, such valves also come with risks. They are associated with blood clots, which means that people who use mechanical heart valves must take anticoagulant medications for life. In addition, the risk of endocarditis is much higher in people with mechanical valves and patients may need to take prophylactic antibiotics before certain types of procedures in order to address this issue.
When a mechanical heart valve is placed inside a patient, the patient will be under general anesthesia and a heart-lung machine will be used to temporarily take over for the heart so that the heart will be still for the surgery. After the surgery is complete and the patient is successfully taken off bypass, he or she can be moved into recovery. Patients may need to stay in the hospital for up to two weeks after a valve replacement surgery so that they can be monitored.