Does thrombocytopenia predict short-term mortality after transcatheter and surgical aortic valve replacement?

OBJECTIVE: Postprocedural thrombocytopenia is frequently observed after transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (sAVR), but its independent prognostic value remains unclear. We investigated whether platelet reduction after TAVI and sAVR independently predicts short-term mortality beyond baseline procedural risk. METHODS: This retrospective single-center study included 216 patients who underwent aortic valve replacement between 2015 and 2020. Sixty-seven patients underwent TAVI and 149 underwent sAVR. Mechanical valve recipients were retained in the overall cohort but excluded from the primary TAVI-sAVR comparison. Propensity score overlap weighting was used to reduce baseline differences between groups. Longitudinal changes in platelet count (PLT), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) were evaluated using generalized estimating equation models, and factors associated with 90-day mortality were assessed using Firth penalized logistic regression. RESULTS: The primary comparative cohort included 67 TAVI and 93 sAVR patients. After overlap weighting, adequate balance was achieved for all measured baseline covariates. Significant treatment × time interactions were observed for PLT (p = 0.001), NLR (p < 0.001), and PLR (p = 0.002). On postprocedural day 3, moderate thrombocytopenia was more frequent after sAVR than TAVI (33.5% vs. 8.3%), whereas normal platelet levels were more frequent after TAVI (45.6% vs. 8.2%; overall p < 0.001). Weighted 90-day mortality did not differ significantly between TAVI and sAVR (12.6% vs. 17.5%, p = 0.487). In Firth regression models, only EuroSCORE II remained independently associated with 90-day mortality. CONCLUSION: Postprocedural platelet and inflammatory responses showed different temporal patterns after TAVI and sAVR. However, these biomarker changes were not independently associated with 90-day mortality after adjustment, whereas EuroSCORE II remained independently associated with mortality. Serial hematological changes should therefore be interpreted together with baseline clinical risk rather than as isolated prognostic markers.