Impact of postprocedural thrombocytopenia on mortality after transcatheter aortic valve implantation

AIMS: We performed a meta-analysis of currently available studies investigating the impact of postprocedural thrombocytopenia on mortality after transcatheter aortic valve implantation (TAVI). METHODS: All studies researching the impact of postprocedural thrombocytopenia on mortality after TAVI were identified after searching PubMed and Web of Science through July 2019. The outcome of interest was early (in-hospital or 30-day) and overall (1- to 2-year) all-cause mortality after TAVI. From each study, the number of deaths in both patients with major (moderate/severe or higher postprocedural drop platelet counts defined in each study) and nonmajor (no/minor or lower drop platelet counts defined in each study) postprocedural thrombocytopenia was extracted. Then, odds ratios (ORs) of mortality for major vs. no/minor thrombocytopenia and their confidence intervals were generated. Alternatively, ORs and hazard ratios of mortality for major vs. no/minor thrombocytopenia (if available, adjusted) were directly extracted. Study-specific estimates were pooled in both the fixed-effect and random-effects models. RESULTS: The principal pooled analysis demonstrated that postprocedural thrombocytopenia was associated with statistically significant increases in early (OR, 3.79; P for effect <0.00001; P for heterogeneity = 0.89) and overall mortality (OR/hazard ratio, 1.22; P for effect = 0.009; P for heterogeneity = 0.17) in the fixed-effect model. All sensitivity analyses did not substantively alter the results of the principal analysis. No funnel plot asymmetry of the principal analysis was detected (P for early mortality = 0.88; P for overall mortality = 0.14), which suggested probably no publication bias. CONCLUSION: Postprocedural thrombocytopenia is associated with increased early and overall mortality after TAVI.