Early post-TAVI thrombocytopenia recovery and subsequent subclinical leaflet thrombosis

Abstract Objective Post-implant thrombocytopenia and subclinical leaflet thrombosis (SLT) are two common phenomena, yet their potential interplay remains unexplored. This study aimed to determine whether early platelet dynamics differed in patients diagnosed with SLT on multidetector computed tomography (MDCT) compared with those without SLT. Methods and results A total of 118 consecutive patients treated with self-expandable supra-annular and intra-annular prostheses were longitudinally analysed. Platelet count was assessed using the corrected platelet count (CPC) from baseline to day 7 (or hospital discharge) and at 30 days. Platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR) were also measured as inflammatory markers. Spleen volume was assessed at baseline. MDCT was performed at 6-month follow-up to evaluate SLT. SLT, ranging from mild to severe, was detected in 22 patients at the 6-month MDCT follow-up. The SLT group had a lower baseline platelet count compared to the No-SLT group, with persistently lower levels from day 1 to day 7 post-implant. Platelet count was significantly lower in the SLT group on days 5 and 6 (CPC: 170 (IQR: 50) × 10³/μL vs. 215 (IQR: 72) × 10³/μL, P = 0.048; and 175 (IQR: 55) × 10³/μL vs. 240 (IQR: 85) × 10³/μL, P = 0.038). No significant differences were observed in PLR or LMR. Spleen volume was also significantly lower in the SLT group. Conclusion We demonstrated a reversible thrombocytopenia during the first week post-implant, which was more pronounced in the SLT group than in the No-SLT group. Additionally, spleen volume was smaller in the SLT group, suggesting a potential interplay between these factors.