The aim of this study was to retrospectively compare modified Del Nido and blood-based St. Thomas cardioplegia in adult patients undergoing isolated aortic valve replacement (AVR). This retrospective study included adult patients undergoing isolated AVR because of aortic valve stenosis between 2024 and 2025. Patients were stratified into blood-based St. Thomas and modified Del Nido groups. The main modification of the Del Nido solution was the adjustment of the crystalloid-to-blood ratio to 1:4. Preoperative and perioperative variables, as well as postoperative biomarkers, including high-sensitivity troponin I, creatine kinase (CK), CK-MB, and lactate, were analyzed. A total of 93 patients were included in the study (blood-based St. Thomas: n = 22; modified Del Nido: n = 71). No significant differences were observed in cardiopulmonary bypass time [98 min (IQR 84-110) vs. 90 min (IQR 74-110); p = 0.184] or aortic cross-clamp time [75 min (IQR 67-86) vs. 73 min (IQR 62-87); p = 0.345]. High-sensitivity troponin I levels at 24 h were numerically, but not statistically significantly, lower in the blood-based St. Thomas group [1961 ng/L (IQR 1367-4423) vs. 2819 ng/L (IQR 1698-5054); p = 0.240]. CK levels at 6 h were comparable between the groups [8.4 μkat/L (IQR 6.5-10.1) vs. 8.5 μkat/L (IQR 6.0-12.7); p = 0.632], as were CK-MB and lactate levels at all evaluated time points. In exploratory multivariable analyses adjusted for age, sex, preoperative LVEF, cardiopulmonary bypass time, and aortic cross-clamp time, cardioplegia type was not independently associated with postoperative biomarker levels. The less frequent dosing and membrane-stabilizing properties of modified Del Nido cardioplegia did not translate into statistically significant clinical or biochemical advantages in the setting of relatively short, isolated AVR procedures.

Aortic stenosis is predominantly treated through transcatheter bioprosthetic heart valve implantation. However, the materials used in these devices are prone to premature failure. Polymer heart valves provide an alternative to current commercial devices, offering materials with greater durability and customisation through fibre reinforcement. Given the wide range of available materials and structures, there is a need for a systematic and efficient approach to designing and optimising novel bioinspired polymeric leaflets. This work presents a framework that employs computational modelling and Design of Experiments (DOE) tools to optimise bioinspired, 3D-printed, fibre-reinforced polymer leaflets made using melt electrowriting (MEW). Here, finite element (FE) models are created to represent MEW fibre-reinforced polymer leaflets for application in a transcatheter aortic heart valve. The behaviour of this valve under physiological loading conditions is modelled to predict valve performance and leaflet material response. These models were first used to investigate the impact of fibre orientation on valve performance and leaflet response, thereby demonstrating the benefits of a bioinspired fibre reinforcement structure. Using a DOE approach, the structural combination of MEW fibre reinforcement and an elastomeric matrix was optimised to improve valve performance and reduce leaflet stress and strain. Overall, the framework offers an efficient and versatile methodology for optimising fibre-reinforced polymer leaflets using an in silico approach, thereby reducing the need for physical prototyping and testing of these next-generation devices during early product development.

BackgroundBicuspid aortic valve (BAV) disease is a leading cause of aortic stenosis (AS). Surgical aortic valve replacement (SAVR) has traditionally been regarded as the best therapeutic option for bicuspid AS. However, the distinctive anatomical characteristics of BAV make the treatment with transcatheter aortic valve replacement (TAVR) challenging, so this population was often excluded from the trials. We aimed to compare TAVR and SAVR in terms of safety and efficacy in the population with bicuspid AS.MethodsWe conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies, searched from PubMed, Cochrane, Scopus, and Web of Science (from inception until September 2025). Dichotomous outcomes were pooled as risk ratios (RRs), and continuous outcomes as mean differences (MDs), each with 95% confidence intervals (CIs).ResultsA total of 78,677 patients were included in one RCT, 12 retrospective cohort studies, and one prospective cohort study. TAVR, compared to SAVR, was associated with significantly higher rates of permanent pacemaker implantation (PPI) (O.R. = 2.29, 95% C.I. [1.51, 3.47], P < 0.01) and shorter length of hospital stay (M.D. = -2.24, 95% C.I. [-3.96, -0.52], P = 0.01) and lower bleeding rates (O.R. = 0.31, 95% C.I. [0.14, 0.69], P < 0.01). However, there were no significant differences in all-cause mortality (ACM) (P = 0.948), acute kidney injury (AKI) (P = 0.28), stroke incidence (P = 0.475), and vascular complications (P = 0.31). The PPI and stroke rate results were consistent during in-hospital and short-term follow-ups. However, subgroup analysis by follow-up duration revealed that long-term stroke incidence was significantly higher in the TAVI group.ConclusionTAVR offers benefit by minimizing significant bleeding and hospital length of stay. However, the benefits should be balanced against the considerably increased risk of PPI and PVL. Further RCTs are needed to confirm these findings.