BIOLOGICAL PROSTHESES IN PATIENTS YOUNGER THAN 65 YEARS OLD: A PROPENSITY-SCORE MATCHING ANALYSIS BETWEEN THE TWO MOST IMPLANTED BOVINE PERICARDIAL VALVES.

Background and Aim: The latest ESC/EACTS guidelines recommend the use of biological prostheses in patients over 65 years old for aortic valve replacement. However, in recent years, there has been an increasing use of bioprosthetic valves in younger patients as well. This study aimed to compare the six-year results in ≤65 years old patients receiving the last two generation of bovine pericardial valves (Perimount Magna Ease and Inspiris Resilia) in the aortic position. Methods: From 2017 to 2023, clinical and echocardiographic data of patients receiving PME and IR prosthesis for isolated or combined AVR were prospectively collected at our Institution. Propensity score (PS) matching was performed to compare the groups at 6-years follow-up. Results: A total of 2053 patients were included: 1602 PME and 451 IR. After propensity score matching, 224 pairs of patients with similar risk profiles were compared. IR valve showed good six–year freedom from explant, endocarditis and stroke comparable to PME valve. However, causes of cardiovascular mortality should be better assessed in PME patients (Log-rank test p=0.028). Infective Endocarditis was the main cause of valve explant in both cohorts (46.7% in PME vs 53.3% in IR). After an initial lower transproshtetic mean gradients and peak velocity in IR valves, PME and IR valve showed comparable hemodynamic from 1 to 6 years of follow- up. Conclusions: In patients under 65 years of age, the new generation of IR prostheses showed good clinical and echocardiographic results similar to those of PME prostheses; however, with lower cardiovascular mortality at 6 years.