ObjectiveTo analyze the characteristics of platelet changes and their influencing factors during postoperative hospitalization in patients who underwent transcatheter aortic valve implantation (TAVI). MethodsThe patients who underwent TAVI at Beijing Anzhen Hospital Valve Surgery Center between March 2017 and October 2021 were retrospectively selected. The patients were divided into a self-limiting group and a non-self-limiting group according to the characteristics of postoperative platelet decline. In addition, the general preoperative data, preoperative and postoperative ultrasound data, intraoperative data, and the use of anticoagulant drugs during the postoperative stay in the hospital were compared between the two groups. ResultsA total of 249 patients were enrolled in this study. There were 175 (70.3%) patients in the self-limiting group, including 100 males and 75 females, and there were 74 (29.7%) patients in the non-self-limiting group, including 43 males and 31 females, with no statistical difference between the two groups (P=0.863). The mean age of patients was 73.11±8.88 years in the self-limiting group and 71.54±10.39 years in the non-self-limiting group (P=0.231). The decline of platelets in the self-limiting group generally occurred on the postoperative day 2 and reached the lowest count on the postoperative day 4, and returned to the baseline level on the postoperative day 5-7, while the platelets in the non-self-limiting group changed by simple rise, fall or irregular fluctuation. Patients in the self-limiting group had severer preoperative aortic stenosis (P<0.001) and used more extracorporeal circulation assistance during surgery (P<0.001). Postoperatively, patients in the self-limiting group were more likely to have periaortic valve leakage than those in the non-self-limiting group (P=0.013). ConclusionPlatelet changes in most patients after TAVI show a self-limiting decline, which may be related to the severity of patients’ preoperative aortic stenosis, intraoperative extracorporeal circulation device use, and postoperative perivalvular leakage.