Hypo-attenuated leaflet thickening after surgical aortic valve replacement with INSPIRIS RESILIA valve

Objectives To investigate the incidence and early clinical impact of hypo-attenuated leaflet thickening (HALT) after surgical aortic valve replacement (SAVR) using the INSPIRIS RESILIA valve. Methods Between August 2020 and January 2025, 182 patients underwent SAVR with the INSPIRIS RESILIA valve, of whom 121 (66.5%) underwent cardiac computed tomography 1 week postoperatively. Anticoagulation consisted of heparin (target activated partial thromboplastin time, 1.5-2.0× control) followed by warfarin (target prothrombin time-international normalized ratio [PT-INR], 1.6-2.5). Parameters were compared between the HALT and non-HALT groups. Results HALT was detected in 22.3% (27/121) of patients. Among warfarin-treated patients (n = 94), mean PT-INR was 1.7 in the HALT group and 1.8 in the non-HALT group (p = 0.61). Patients with HALT were older (76.2 vs. 73.0 years, p = 0.10), and sex-adjusted odds ratio of HALT was 4.68 for patients aged ≥ 80 years as compared with those aged < 70 years (p = 0.03). Those with HALT had lower body surface area (1.46 vs. 1.58 m2, p = 0.002). HALT was not associated with impaired early prosthetic valve function, and no patient had a mean pressure gradient > 20 mmHg. No in-hospital deaths or thromboembolic events were reported. No cerebral infarction occurred in the HALT group, whereas two occurred in the non-HALT group (p = 1.00). Conclusions HALT occurred in approximately one-fifth of patients after SAVR with the INSPIRIS RESILIA valve. No signal of an increased risk of thromboembolic events associated with HALT was observed in this small cohort with a short-term follow-up.