[Dysfunction of valvular prostheses].

Implantation of artificial mechanic valvular prostheses significantly improves and prolong the life of patients with valvular defects with a haemodynamic impact. This therapeutic method does not cure the patients and operation switches the problem of a natural dysfunctional valve to that of a functional artificial valve with improvement of the quality of life and its prolongation. The long-term effect and thus the general prognosis--the patient's "fate" depends above all on complications such as infections and haemocoagulation which are the main cause of dysfunction of artificial prostheses. The authors describe in the submitted paper basic principles of prevention of these undesirable events and decisive steps which must be taken to ensure a rapid and accurate diagnosis of imminent of already developed dysfunction of the prosthesis and its solution under the given conditions.