Heart valve replacement - overview

Replacement of damaged cardiac valves with prosthesis has now become a common and often life-saving therapeutic intervention. A prosthetic or artificial heart valve is used to replace a diseased or dysfunctional heart valve.

There are 2 types of artificial valves, mechanical and biological. A mechanical heart valve is made of man-made materials such as caged balls, tilting disks or hinged semi-circular flaps. The advantage of mechanical valves is that they can usually last a lifetime. They do not wear out as natural or biological valves do. Biological heart valves are made from tissue taken from animals or human cadavers. They are treated with preservatives and sterilized for human implantation.

A prosthetic heart valve is used to replace a heart valve that leaks, or has thickened, hardened, or stretched. If the valve fails to open and close properly, it decreases the efficiency of blood flow through the heart, and results in an increased workload. Over time, this can lead to heart failure. Two conditions that may require heart valve replacement are stenosis and regurgitation. In stenosis, the valve has a smaller opening than the original valve. The heart has to work much harder at pushing the blood through. Over time, this can cause strain on a heart, which can be life-threatening. In regurgitation, the valve leaks, allowing blood to flow backwards through the heart. In addition to potential surgical complications, patients with prosthetic valves are more susceptible to endocarditis and valvular degeneration. They must also be maintained on a regimen of anti-coagulant medications in order to prevent clot formation on the prosthetic valve. As an alternative to valve replacement, a stenotic valve can sometimes be repaired using a catheterization procedure.