Transcatheter implantation of the aortic valve is indicated in patients with severe, symptomatic aortic stenosis, with an endangered life outcome who, due to the high risk, are not suitable candidates for classic, surgical valve replacement. Thrombocytopenia after TAVI is a common occurrence, but the underlying mechanisms are poorly known and explained. A retrospective study was conducted at the Department of Cardiovascular Diseases, Clinical Hospital Center Rijeka in 2022. 89 patients underwent a TAVI procedure with achieved hemostasis of the femoral vascular access with percutaneous closure systems Perclose ProGlideTM Suture-mediated Closure System,Manta Vascular Closure Device (VCD) and a combination Perclose ProGlideTM Suture-mediated Closure System+Angio-Seal. Analyzing the results, a statistically significant difference was obtained between the values of the platelet count at admission and after the TAVI procedure, as well as in the hemoglobin values before and after the procedure. Observing the mean values of hemoglobin before and after the procedure, we see that the change in the form of a drop is most significant when using the Proglide device, where the mean value of the minimum number of platelets during hospitalization is the lowest. Manta had a smaller drop in the mean value of hemoglobin after the procedure and a slightly higher mean value of the minimum number of platelets. It correlates with BARC 1 for hemoglobin, but with BARC 2 for platelet values, which is one degree more severe than the observed BARC 1 with Proglide despite higher minimum platelet values. In the case of Manta, hospitalizaton was the shortest, and in Proglide the longest, but due to the differences in the number of respondents, we cannot consider this information relevant enough to judge the quality of an individual system. The main variable - the number of platelets has been proven to change in a descending sense as a result of the TAVI procedure.