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.