The Use of Biological Heart Valves.

BACKGROUND

Biological heart-valve prostheses have undergone continuous devel- opment up to the present, and technological advances have been made in catheter- assisted valve systems (transcatheter aortic valve implantation, TAVI) and minimally invasive routes of application. These parallel trends have led to major changes in therapeutic strategies, widening the spectrum of patients who are candidates for biological aortic valve implantation.

METHODS

This review is based on pertinent publications retrieved by a systematic search in PubMed employing the search terms "conventional biological aortic pros- thesis," "rapid deployment prosthesis," and "transcatheter aortic valve implantation/ replacement."

RESULTS

Among biological heart-valve prostheses, a distinction is drawn between stented (conventional, rapid-deployment, and catheter-assisted) and non-stented types. The long-term durability of conventional, surgically implantable biological valve protheses is by far the best documented: the reported 5-year reoperation rates range from 13.4% to 36.6%, and the pacemaker implantation rate is ca. 4%. Rapid-deployment prostheses combine the advantages of conventional and ca- theter-assisted techniques and facilitate minimally invasive approaches. The TAVI method is currently recommended for high- and intermediate-risk patients, while conventional valve replacement remains the method of choice for those at low risk. Rapid-deployment and TAVI prostheses is associated with a higher pacemaker im- plantation rate than conventional prostheses: these rates are 8.5-15.3% for TAVI and 6.0-8.8% for rapid-deployment valves. The intermediate-term durability of catheter-assisted and rapid-deployment prostheses appears promising, but their long-term durability is still unclear.

CONCLUSION

The further development of biological heart-valve prostheses in the form of improved conventional, transcatheter, and rapid-deployment prostheses now enables individualized treatment. Before any such procedure is performed, the car- diac team must assess the patient's risk profile and the advantages and disadvan- tages of each type of prosthesis to determine which is best.