Outcomes for In-Hospital Thrombocytopenia after TAVI

Objectives: Transcatheter aortic valve implantation (TAVI) is an attractive treatment for patients with aortic valve stenosis. Nevertheless, postoperative thrombocytopenia is regularly observed. The reasons and impact for this phenomenon are unknown at so far. We aimed to assess incidence, risk factors and outcomes of thrombocytopenia following TAVI.

Methods: We performed a retrospective analysis of patients who underwent TAVI in our center between 2009 and 2018. All patients affected by prior thrombocytopenia were excluded. Postoperative platelet count was corrected for hematocrit (CPC), to reduce the possible bias due to the hemodilution. Endpoints of this study were in-hospital mild thrombocytopenia (“MT,” defined as a CPC < 100,000/µL) and severe thrombocytopenia (“ST,” defined as a CPC<50,000/µL). Outcomes were compared with no-thrombocytopenia group (NoT). Multivariate logistic regression was used to determine the baseline variables associated with the outcomes.

Result: A total of 907 patients were analyzed. MT and ST were observed in 28.1 and 2.6%, respectively. MT patients were more frequent female (p = 0.002), otherwise we did not observe any baseline differences (mean age: NoT, 81.7; MT, 82; ST, 82.9 years; mean platelet count: NoT, 247.2; MT, 172.9; ST, 176.9000/µL). In both MT and ST group, the lowest CPC was found on the 3rd and 4th postoperative days. MT was uniformly distributed in all prosthesis group (self-expandable = 31.6%; balloon expandable = 26.6%). ST was observed mainly in balloon-expandable group (3.6%). Only one person in the self-expandable group had ST (0.37%). On the logistic regression, the preoperative hematocrit, the preoperative number of platelets, the access, and paroxysmal atrial fibrillation were found to be significant predictors of MT. ST was associated with preoperative platelet count, transapical access, and the use of a balloon-expandable prosthesis. Following clinical outcomes were recorded: incidence of life-threating and major bleeding (NoT: 14.2%, MT: 20.8%, ST: 58.3%), median length of hospital stay (NoT: 8, MT: 10, ST: 14 days), in-hospital mortality (NoT: 4%, MT: 6.3%, ST: 16.7%) and reached significance in comparison with NoT (p < 0.05).

Conclusion: Both MT and ST following TAVI are associated with a worse clinical outcome. According to our analysis, MT is frequent, and occurs uniformly in all prostheses groups. ST is less common but more frequent with the use of a balloon-expandable prostheses. A low baseline platelet count and transapical access are associated with both MT and ST.

Publication History

Article published online:
19 February 2021