Aortic valve replacement has been applied for over half a century. Two classes of devices have been developed: mechanical and biological valve prostheses. For biological devices, autografts, homografts and xenografts (porcine and pericardial) have been developed. For mechanical devices, cage ball, tilted disc and bi-leaflet valves have been designed.
For BHV, the main drawback is a limited durability, the main advantage is the low rate for TE events, which obviates the need for peroral anticoagulation. Age is a major determinant for durability. In contrast, MHV are very durable, but they require a lifelong anticoagulation with all their side effects. The choice for a valve in each individual patients depends on several factors: age and life expectancy are the main factors.
In difficult situations, i.e. an age between 55 and 70 years, results of comparative studies might be helpful in the decision making. Comparison should include contemporary devices and techniques. Use of historical series are confounded by changes and improvements in peri and postoperative care. A RCT remains the gold standard, but these are few in numbers.
The only recent RCT did not change much: the outcome is still more dependent on patient related factors than on the type of the valve, except 1) for bleeding, which is more common with MHV and 2) for SVD, which is observed with BHV. These observations are hardly surprising.
Results for a twenty-year follow-up might be needed. The preference of physician and patients for the choice of a valve is important. The dilemma between anticoagulation related bleeding and SVD remains for the time being.
Keywords: Anticoagulation, autografts, biological heart valve prosthesis, bleeding, calcification, effective orifice area, homografts, mechanical heart valve prosthesis, mortality, stentless xenografts, structural valve degeneration, thrombembolism, transvalvular gradient, tissue engineered heart valves, valve prosthesis patient mismatch.