Comparison of the Frequency of Thrombocytopenia After Transfemoral Transcatheter Aortic Valve Implantation Between Balloon-Expandable and Self-Expanding Valves

Abstract

Thrombocytopenia after transcatheter aortic valve implantation (TAVI) is common and has been related to worse clinical outcomes. Comparison of platelet kinetics among different types of valves is limited. Our objectives were to analyze the differences in drop platelet count (DPC) between balloon-expandable valves (BEVs) and self-expanding valves and their prognostic implications after TAVI. Patients who underwent transfemoral TAVI from 2008 to 2016 were included. Exclusion criteria were severe baseline thrombocytopenia and periprocedural death. Postprocedural platelet counts were collected. Two groups were created: DPC ≤30 and DPC >30%. Valve Academic Research Consortium-2 criteria were used to define outcomes. Study population included 609 patients (age 84.7 ± 6.0, 46.6% males). The mean DPC was 32.5 ± 13.9%. The DPC was higher in the BEV arm (33.9 ± 14.2 vs 30.7 ± 13.4%, p = 0.006), and the nadir was reached later in comparison to the self-expanding valve arm (3.0 ± 1.3 vs 2.5 ± 1.1 days, p <0.001). After multivariable analysis, the use of BEV, known coronary artery disease, and left ventricle ejection fraction were the factors associated with a higher rate of DPC >30%. At 30 days, the DPC >30% was related with a higher rate of life-threatening and/or major bleeding (6.8 vs 2.1%, p = 0.009) and death (3.5 vs 0.8%, p = 0.036). At 1 year, the difference in mortality disappeared. In conclusion, in this cohort of patients, the use of BEV seems to be associated with a higher risk of DPC after TAVI. A DPC ≥30% was related with increased risk of life-threatening and/or major bleeding and death at 30 days. Larger and prospective studies are needed to understand this phenomenon.