Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3720_Библиотеки_им_академика_М_И_Перельмана

In surgical valves, the incidence is higher with MHVs compared with BHVs, higher in the mitral than in the aortic position, and higher in the right-sided PHV than the left-sided PHV [12]. The incidence of surgical PHV thrombosis is significantly lower, but also varies, depending on the study. In a meta-analysis of 5837 patients followed for a total of 31,874 patient years, the annual incidence of PHV thrombosis was 0.03%, and that of TE 0.33% [13]. In a single-center study of 387 consecutively explanted BHVs, the estimated annual incidence of PHV thrombosis was 0.74% based on the total number of valves implanted during the study period. The incident rate varied with valve position. Of the 46 valves found to have thrombosis (11.6% of the total implanted during the study period), 29 were aortic (10.9%), 9 were mitral (12.7%), 7 were tricuspid (12.1%), and 1 was pulmonic. The highest annual incidence of thrombosis occurred in the tricuspid position, with a rate of 1%. Observed rates were higher with certain valve types, with subtherapeutic anticoagulation, and in the early perioperative period. Thromboembolic events occurred annually in 2.5%e3.7% of patients with MHV, which may or may not have originated from the valve [14]. Some of the differences in the incidence of both surgical valves and THV thrombosis found in these studies may be related to the variations in methodology, diagnostic methods, and definitions of valve thrombosis adopted by the earlier studies.