Platelet Reduction after Transcatheter Aortic Valve Implantation: Results from the PORTRAIT Study

Abstract

Background: An unexplained condition that follows transcatheter aortic valve implantation (TAVI) is platelet count reduction (PR). According to published research, patients with balloon-expandable valves (BEVs) had a greater PR than those with self-expandable valves (SEVs). Objectives: The purpose of this study was to investigate the incidence and clinical effects of PR following TAVI. Methods: In total, 1.122 adult TAVI patients were enrolled. Propensity score matching was carried out in a 1:1 ratio between patients with BEVs and those with SEVs. The analysis included changes in platelet count, in-hospital mortality, and early postoperative adverse events. Results: Notably, 632 patients were matched (BEV:316; SEV:316). All patients’ post-procedural platelet counts changed according to a parabolic curve, using a mixed regression model for repeated analyses (estimate = −0.931; standard error = 0.421; p = 0.027). The platelet count varied comparably in patients with BEVs and SEVs (estimate = −4.276, standard error = 4.760, p = 0.369). The average time for obtaining the nadir platelet count value was three days after implantation (BEV: 146 (108–181) vs. SEV: 149 (120–186); p = 0.142). Overall, 14.6% of patients (92/632) had post-procedural platelet count <100,000/µL. There was no difference between the two prosthesis types (BEV:51/316; SEV:41/316; p = 0.266). Thrombocytopenia was found to be significantly linked to blood product transfusions, lengthier stays in the intensive care unit and hospital, and in-hospital mortality. Conclusions: TAVI, irrespective of the type of implanted valve, is linked to a significant but temporary PR. Thrombocytopenia increases the risk of serious complications and in-hospital death in TAVI patients. To explore and clarify the causes and associated effects, further prospective research is necessary.