Biomechanical and histological evaluation of a prototype bovine pericardial patch for veterinary abdominal surgery: An approximation study.

In veterinary medicine, especially within large animal medical and surgical clinics, addressing cavitary defects is a primary concern. In bovines, umbilical hernias are the most common defect, and surgical repair often necessitates the use of prosthetic materials. However, there is a high rate of recurrence with sutures or synthetic meshes, largely due to tissue contamination. The development of biological patches for such repairs is still in its early stages in veterinary medicine, with no commercially tested prototypes available in Argentina. Tissues derived from the extracellular matrix are considered for this purpose, with bovine pericardium standing out due to its architectural characteristics and mechanical properties. For an ideal membrane, the pericardium must retain its biomechanical properties while being unreactive and safe for the host. This study aimed to biomechanically and histologically characterize a bovine pericardium patch through all stages of processing. The treatment involved fixation with 0.5 % glutaraldehyde, immersion in an antibiotic/antimycotic solution, and detoxification and storage in a 98 % sterile glycerin solution, with three sodium phosphate-buffered washes between steps. Histological examinations and stress-strain tests were performed at each processing stage, using native pericardium as a control. Despite some minor modifications in the histological and mechanical properties, the final patches appear to be a viable alternative for resolving cavitary defects.

Biological tissue for transcatheter aortic valve: The effect of crimping on fatigue strength.

Transcatheter aortic valve replacement (TAVR) has become today the most attractive procedure to relieve patients from aortic valve disease. However, the procedure requires crimping biological tissue within a metallic stent for low diameter catheter insertion purpose. This step induces specific stress in the leaflets especially when the crimping diameter is small. One concern about crimping is the potential degradations undergone by the biological tissue, which may limit the durability of the valve once implanted. The purpose of the present work is to investigate the mechanical damage undergone by bovine pericardium tissue during compression and analyze how this degradation evolves with time under fatigue testing conditions. Pericardium 500 µm thick pericardium ribbons (5 mm large, 70 mm long) were crimped down to 12 Fr for 30 and 50 min within a metallic stent to replicate the heart valve crimping configuration. After crimping, samples underwent cyclic fatigue flexure and pressure loading over 0.5 Mio cycles. Samples were characterized for mechanical performances before crimping, after crimping and after fatigue testing in order to assess potential changes in the mechanical properties of the tissue after each step. Results bring out that the ultimate tensile strength is not modified through the process. However an increase in the modulus shows that the crimping step tends to stiffen the pericardium. This may have an influence on the lifetime of the implant.

A case image of epicardial implants in a young male with mixed germ cell tumor.

Epicardial metastasis from mixed germ cell tumors is exceedingly rare and poses a significant risk for cardiac morbidity. This case highlights the crucial need for comprehensive systemic evaluation in patients with known malignancies presenting with cardiac symptoms.

The interaction of lipomatous hypertrophy of the interatrial septum with pericardial adipose tissue biomarkers by computed tomography.

OBJECTIVE: Novel pericardial adipose tissue imaging biomarkers are currently under investigation for cardiovascular risk stratification. However, a specific compartment of the epicardial adipose tissue (EAT), lipomatous hypertrophy of the interatrial septum (LHIS), is included in the pericardial fat volume (PCFV) quantification software. Our aim was to evaluate LHIS by computed tomography angiography (CTA), to elaborate differences to other pericardial adipose tissue components (EAT) and paracardial adipose tissue (PAT), and to compare CT with [18F]FDG-PET. MATERIALS AND METHODS: Of 6983 patients screened who underwent coronary CTA for clinical indications, 190 patients with LHIS were finally included (age 62.8 years ± 9.6, 31.6% females, BMI 28.5 kg/cm2 ± 4.7) in our retrospective cohort study. CT images were quantified for LHIS, EAT, and PAT density (HU), and total PCFV, with and without LHIS, was calculated. CT was compared with [18F]FDG-PET if available. RESULTS: CT-density of LHIS was higher (- 22.4 HU ± 22.8) than all other pericardial adipose tissue components: EAT right and left (97.4 HU ± 13 and - 95.1 HU ± 13) PAT right and left (- 107.5 HU ± 13.4 and - 106.3 HU ± 14.5) and PCFV density -83.3 HU ± 5.6 (p < 0.001). There was a mild association between LHIS and PAT right (Beta 0.338, p = 0.006, 95% CI: 0.098-577) and PAT left (Beta 0.249, p = 0.030; 95% CI: 0.024-0.474) but not EAT right (p = 0.325) and left (p = 0.351), and not with total PCFV density (p = 0.164). The segmented LHIS volume comprised 3.01% of the total PCFV, and 4.3% (range, 2.16-11.7%) in those with LHIS > 9 mm. [18F]FDG-PET: LHIS was tracer uptake positive in 83.3% (37.5%: mild and 45.8%: minimal) of 24 patients. CONCLUSIONS: LHIS is a distinct compartment of PCFV with higher density suggesting brown fat and has no consistent association with EAT, but rather with PAT. CLINICAL RELEVANCE STATEMENT: LHIS should be recognized as a distinct compartment of the EAT, when using EAT for cardiovascular risk stratification. KEY POINTS: LHIS is currently included in EAT quantification software. LHIS density is relatively high, it is not associated with EAT, and has a high [18F]FDG-PET positive rate suggesting brown fat. LHIS is a distinct compartment of the EAT, and it may act differently as an imaging biomarker for cardiovascular risk stratification.

Outcomes of surgical correction of Peyronie's disease with plaque excision and grafting: Comparison of testicular tunica vaginalis graft versus bovine pericardium graft.

Objective: Peyronie's disease (PD) is an abnormal wound healing in the penile tunica albuginea. After fibrotic plaque excision, different graft materials have been used to repair the defects, but the optimal graft remains unknown. This study aimed to compare the functional outcomes of testicular tunica vaginalis grafts and bovine pericardium grafts in patients with severe PD. Methods: A retrospective comparative study was conducted on 33 PD patients undergoing partial plaque excision and grafting from September 2015 to May 2021. The patients were divided into two groups depending on the type of graft used. For 15 patients in Group B, testicular tunica vaginalis grafts were used to repair the defect, while for 18 patients in Group A, bovine pericardium grafts were used. Data of the patient's age, comorbidities, sexual function, penile curvature, postoperative complications, need for further treatment, change in penile length, and satisfaction were gathered and compared between the groups. Sexual function was evaluated using the 5-item version of the International Index of Erectile Function (IIEF-5), and a functional less than 20-degree penile curvature after surgery was considered a successful intervention. Results: There was no difference in age, comorbidities, degree of curvature, perioperative IIEF-5, operative time, plaque size, or complication rates. After surgery, a statistically significant improvement in curvature degree (p<0.05) and satisfactory penile appearance (p<0.05) were seen in both groups without any superiority between the two groups (p=0.423 and p=0.840, respectively). With a 30-month follow-up, the IIEF-5 was consistent in both groups, with no statistical significance between the groups (p=0.492). The main change in penile length during the operation was increased and still positive in the last follow-up in both groups without statistical significance (p=0.255 and p=0.101, respectively). Conclusion: Partial plaque excision and corporoplasty with both testicular tunica vaginalis or bovine pericardium grafts are equally effective in treating males with clinically significant PD.

Characterization of a decellularized pericardium extracellular matrix hydrogel for regenerative medicine: insights on animal-to-animal variability.

In the past years, the use of hydrogels derived from decellularized extracellular matrix (dECM) for regenerative medicine purposes has significantly increased. The intrinsic bioactive and immunomodulatory properties indicate these materials as promising candidates for therapeutical applications. However, to date, limitations such as animal-to-animal variability still hinder the clinical translation. Moreover, the choice of tissue source, decellularization and solubilization protocols leads to differences in dECM-derived hydrogels. In this context, detailed characterization of chemical, physical and biological properties of the hydrogels should be performed, with attention to how these properties can be affected by animal-to-animal variability. Herein, we report a detailed characterization of a hydrogel derived from the decellularized extracellular matrix of bovine pericardium (dBP). Protein content, rheological properties, injectability, surface microstructure, in vitro stability and cytocompatibility were evaluated, with particular attention to animal-to-animal variability. The gelation process showed to be thermoresponsive and the obtained dBP hydrogels are injectable, porous, stable up to 2 weeks in aqueous media, rapidly degrading in enzymatic environment and cytocompatible, able to maintain cell viability in human mesenchymal stromal cells. Results from proteomic analysis proved that dBP hydrogels are highly rich in composition, preserving bioactive proteoglycans and glycoproteins in addition to structural proteins such as collagen. With respect to the chemical composition, animal-to-animal variability was shown, but the biological properties were not affected, which remained consistent in different batches. Taken together these results show that dBP hydrogels are excellent candidates for regenerative medicine applications.

Complete Aortic Valve Reconstruction with Autologous Pericardium: Analysis of Mid-Term Results of Single-Center Experience with AVNeo Procedure.

PURPOSE: Aortic valve neocuspidization (AVNeo) is a relatively recent advancement in surgical AV replacement. Data on its performance beyond the short term are limited. We assessed the mid-term outcomes in patients undergoing AVNeo, focusing on feasibility, perioperative details, and its role in AV pathology treatment. METHODS: Sixty-five consecutive patients underwent AVNeo between December 2016 and February 2018. Clinical data were prospectively collected and retrospectively analyzed. Tricuspid reconstruction with autologous pericardium was performed in all cases. Echocardiographic follow-up was conducted post-discharge, at 6 and 12 months, and annually thereafter. RESULTS: The mean age was 62.6 ± 18.7 years. AVNeo was feasible in all cases. Concomitant procedures were performed in 43 (66.2%) patients. Mean bypass and cross-clamp times were 119.2 ± 30.3 and 87.1 ± 22.9 minutes, respectively. Postoperative transvalvular hemodynamics was excellent. There was one (1.5%) in-hospital death. Follow-up (mean 66.72 ± 12.77 months) was complete in 58 patients (89.2%). There were no detected valve-related or thromboembolic events. Transvalvular hemodynamic parameters were stable during the observation period: peak pressure gradient at discharge and follow-up was 15.3 ± 4.6 mmHg and 15.01 ± 6.3 mmHg, respectively (ρ = 0.346). CONCLUSIONS: AVNeo demonstrated the feasibility and favorable mid-term outcomes. Studies with longer-term observation are warranted to evaluate its durability.

Pericardial Diseases: International Position Statement on New Concepts and Advances in Multimodality Cardiac Imaging.

Pericardial diseases have gained renewed clinical interest, leading to a renaissance in the field. There have been many recent advances in pericardial diseases in both multimodality cardiac imaging of diagnoses, such as recurrent, transient constrictive and effusive-constrictive pericarditis, and targeted therapeutics, especially anti-interleukin (IL)-1 agents that affect the inflammasome as part of autoinflammatory pathophysiology. There remains a large educational gap for clinicians, leading to variability in evaluation and management of these patients. The latest pericardial imaging (American Society of Echocardiography, European Association of Cardiovascular Imaging) and clinical guidelines (European Society of Cardiology) are >8-10 years of age and may not reflect current practice. Recent clinical trials involving anti-IL-1 agents in recurrent pericarditis, including anakinra (AIRTRIP), rilonacept (RHAPSODY), and goflikicept have demonstrated their efficacy. The present document represents an international position statement from world leaders in the pericardial field, focusing on novel concepts and emphasizing the role of multimodality cardiac imaging as well as new therapeutics in pericardial diseases.

Proprioceptors of the human pericardium.

In the human organism, all functions are regulated and, therefore, require a feedback mechanism. This control involves a perception of the spatial tensile state of cardiac tissues. The presence and distribution of respective proprioceptive corpuscles have not been considered so far. Therefore, a comprehensive study of the entire human fibrous pericardium was conducted to describe the presence of proprioceptors, their density, and distribution patterns. Eight human pericardial specimens gained from our body donation program were used to create a three-dimensional map of proprioceptors in the pericardium based on their histological and immunohistochemical identification. The 3D map was generated as a volume-rendered 3D model based on magnetic resonance imaging of the pericardium, to which all identified receptors were mapped. To discover a systematic pattern in receptor distribution, statistical cluster analysis was conducted using the Scikit-learn library in Python. Ruffini-like corpuscles (RLCs) were found in all pericardia and assigned to three histological receptor localizations depending on the fibrous pericardium's layering, with no other corpuscular proprioceptors identified. Cluster analysis revealed that RLCs exhibit a specific topographical arrangement. The highest receptor concentrations occur at the ventricular bulges, where their size reaches its maximum in terms of diameter, and at the perivascular pericardial turn-up. The findings suggest that the pericardium is subject to proprioceptive control. RLCs record lateral shearing between the pericardial sublayers, and their distribution pattern enables the detection of distinct dilatation of the heart. Therefore, the pericardium might have an undiscovered function as a sensor with the RLCs as its anatomical correlate.

Intrapericardial Administration to Achieve Localized and Targeted Treatment for Cardiac Disease.

Intrapericardial administration has been proposed as an alternative delivery route of pharmacological agents via the bilaminar sac of pericardium surrounding the heart. To date, intrapericardial administration has entailed the localized administration of a broad spectrum of therapeutic agents. These agents include stem cells, extracellular matrix, growth factor, drugs, bioactive materials, and genetic materials, to the heart and coronary arteries. The route not only overcomes the limitations associated with traditional systemic administration methods, but also presents multiple intrinsic advantages over the other approaches, allowing greater therapeutic actions. Intrapericardial administration exhibits versatility in addressing certain cardiac conditions and ongoing research in this field certainly holds promise for further innovations and advancements to improve cardiac treatment. Thus, this review discusses the anatomy and physiology of the pericardium, the intrapericardial administration access routes, the recent application of intrapericardial delivery in the context of cardiac repair as well as the challenges associated with the approach.

Congenital Absence of Pericardium: The Swinging Heart.

Congenital absence of the pericardium (CAP) is an unusual condition discovered, in most cases, incidentally but can potentially lead to fatal complications, including severe arrhythmias and sudden death. Recently, the use of modern imaging technologies has increased the diagnosis of CAP, providing important findings for risk stratification. Nevertheless, there is not yet consensus regarding therapeutic decisions, and the management of patients with CAP remains challenging. In this paper, we discuss the pathophysiological implication of CAP, review the current literature and explain the role of multimodality imaging tools for its diagnosis, management and treatment.

A failing right heart in an eggshell: A case report of idiopathic constrictive pericarditis.

key Clinical Message: Constrictive Pericarditis is a rare fibrotic conversion of the pericardium that results in non-specific clinical symptoms such as hepatomegaly, ascites, pleural effusions, and lower extremity edema. A multi-modal diagnostic approach with cardiac imaging tools, cardiac hemodynamic measurements, and tissue biopsy can be used to diagnose Constrictive Pericarditis. Abstract: Constrictive Pericarditis is a rare complication resulting in the fibrotic conversion of the pericardium secondary to idiopathic, infective, post-surgical, or post-radiation etiologies. The rigid and restrictive nature of the pericardium can result in non-specific symptoms of volume overload that can mimic liver cirrhosis or congestive heart failure. We present the case of a 73-year-old female with constrictive pericarditis who presented with vague symptoms of abdominal pain, abdominal bloating, and bilateral lower extremity edema. This case report highlights the clinical manifestation, invasive, and non-invasive diagnostic work-up, and management of constrictive pericarditis.

A Pericardium Bovine Matrix Pocket in DTI Prepectoral Breast Reconstruction.

Breast reconstructive surgery has evolved significantly over the years. One of the recent advancements is the use of prepectoral implants in combination with synthetic and biological material as a natural and effective coverage. To date, there is little published data on breast reconstruction using acellular bovine pericardium matrix and most concern submuscular breast reconstruction. This study aimed to describe the multicentric-multisurgeon experience in performing direct to implant (DTI) prepectoral breast reconstructions using acellular bovine pericardium matrix (ABPM) pocket. A retrospective multicentric data collection of the all the immediate prepectoral breast reconstructions using acellular bovine pericardium was carried out by the authors. Surgical data including type of mastectomy, axillary surgery, type and size of implant, size of ABPM, duration of surgery were collected for each patient. Postoperative data including adjuvant treatments, complications, necessity to perform other interventions, patient's satisfaction were collected. Cosmetic results were also evaluated by 7 different observers at minimum 1 year follow-up. A total of 65 breast reconstruction were included in the study. Mean follow up was 21.3 months. Average surgical time was 1,42 hours. Minor complications occurred in 4 breasts; major complications occurred in 2 breasts. After 6 months follow-up, 7 patients underwent fat grafting to correct any rippling and /or wrinkling. Breast aesthetic and patients reported outcomes were satisfactory. Not significant capsular contracture was noted at the follow up control. To date, this is the largest study about prepectoral breast reconstruction with ABPM. On the basis of our results, prepectoral breast reconstruction ABPM assisted is a reliable, safe and suitable option providing good patient satisfaction outcomes.

Application of Bovine Pericardium and Expanded Polytetrafluoroethylene Patches in Tricuspid Valvuloplasty after Cardiac Surgery.

Background: Leaflet augmentation is often required to correct an inadequate leaflet size due to leaflet thickening, contracture and junctional fusion in patients with tricuspid valve regurgitation (TR) after left-side valve surgery (LSVS). However, the ideal material for leaflet augmentation remains controversial. This article aims to compare the medium- and long-term results of tricuspid valve repair with bovine pericardium (BP) and expanded Polytetrafluoroethylene (ePTFE) patches for the augmentation of tricuspid leaflets and to compare the durability of the two materials. Methods: From January 2015 to April 2023, a total of 69 patients with severe isolated TR underwent tricuspid valvuloplasty (TVP) by leaflets augmentation with patches in our institute. According to the different types of patches, they were divided into the BP group (n = 44) and the ePTFE group (n = 25). Results: There were 3 perioperative deaths (4.3%), one case was due to low cardiac output syndrome in the BP group, and 2 cases were due to acute respiratory dysfunction syndrome and low cardiac output syndrome in the ePTFE group, respectively. Before discharge, the area of the TR jet on echocardiography decreased from 23.5 ± 9.1 to 4.2 ± 3.4 cm 2 . One case in each group was found to have increased blood flow velocity at the tricuspid orifice. After discharge, one patient in each group underwent repeat TVP, in the BP group because of shortened chordae and in the ePTFE group because of calcification of the patch. During the entire follow-up period, there were 7 cases of severe TR (10.1%), 5 in the BP group and 2 in the ePTFE group, a total of 5 cases of tricuspid stenosis (7.2%), 4 in the BP group and 1 in the ePTFE group, and a total of 6 deaths (8.7%), 5 in the BP group and 1 in the ePTFE group. Transthoracic ultrasound in a patient with tricuspid stenosis suggests stiff leaflet movement and poor motion. Conclusions: Leaflet patch enlargement can be safely used in tricuspid valve repair, but BP patches carry a risk of reduced flexibility and stiffness of movement, and ePTFE patches carries a risk of calcification.

Assessing Genotoxicity of Bovine Pericardium in Guided Tissue Regeneration: Bacterial Reverse Mutation Assay With Exogenous Metabolic Activation.

Introduction Guided tissue regeneration (GTR) is integral to periodontal therapy, facilitating the repair of osseous defects. Due to the widespread use of bovine pericardium (BP) in GTR, a thorough investigation into its genotoxicity is essential for patient safety and treatment efficacy. This study aimed to evaluate the genotoxic effects of local BP in GTR for periodontal osseous defects. Materials and methods The Bacterial Reverse Mutation Assay (Ames test) was used to assess the genotoxic potential of local BP. An exogenous metabolic activation system was employed to evaluate the direct effects of the material on bacterial cells. Results The study investigated the mutagenic effects of local BP across multiple strains of Salmonella typhimurium, utilizing concentrations ranging from 0.3125 mg/plate to 5 mg/plate. While some variability was observed in revertant counts, the generally low SDs suggest a consistent response to the test substance. The maximum revertant count for each strain did not significantly exceed the mean values, indicating the absence of notable outliers or exceptionally high revertant counts at any specific concentration. Based on the data and toxicity assessment criteria, there is insufficient evidence to suggest that the experimental material induces genotoxic effects in the tested bacterial strains under the provided experimental conditions. Conclusion This study assessed the mutagenic potential of local BP membranes used in GTR with the Ames test. Results showed no evidence of mutagenicity, as revertant counts did not exceed twice the negative control in all bacterial strains with exogenous metabolic activation. This suggests that bovine pericardium membranes are safe for medical use under the test conditions. The study highlights the biocompatibility and non-mutagenic nature of BP membranes in GTR for periodontal therapy.

An Alternative Non-Conduit Repair Strategy for Tetralogy of Fallot With Short Segment Pulmonary Atresia.

Tetralogy of Fallot (TOF) with pulmonary atresia is a subset in which it becomes imperative to use an artificial conduit in most cases. The atresia of the pulmonary artery can occur at various levels and be of variable lengths. For long segment pulmonary atresia, a right ventricle to pulmonary artery conduit is unavoidable in patients otherwise suitable for complete bi-ventricular repair with no major aortopulmonary collaterals, based on McGoon and Nakata indices. However, for patients with membranous pulmonary atresia and short segment atresia of the main pulmonary artery, we describe an alternative technique that avoids the use of handmade conduits or bovine jugular vein grafts and utilizes the concept of a monocusp with restoration of continuity from the right ventricular infundibulum to the distal main pulmonary artery. A seven-year-old girl diagnosed with TOF and pulmonary atresia underwent a right ventriculotomy with ventricular septal defect closure. The narrowed outflow tract was widened, and an anastomosis was made directly between the right ventricle and the pulmonary artery. A monocusp was fashioned from autologous pericardium, and the pulmonary artery was reconstructed using bovine pericardium. In TOF with pulmonary atresia, conventional surgery typically uses a valved conduit to connect the right ventricular outflow tract (RVOT) to the pulmonary artery. However, in cases like ours, direct anastomosis is possible due to a long confluent pulmonary segment. This alternative technique eliminates the need for an artificial conduit and may prevent associated problems. It also allows for potential growth of the neo-annulus and pulmonary segment. The risk of reoperation remains due to possible monocusp failure.

The feasibility and safety of biomaterials for posterior scleral reinforcement in rabbits.

To explore the feasibility and safety of biomaterials for posterior scleral reinforcement (PSR) in rabbits. Decellularization and genipin crosslink were applied to the fresh bovine pericardium and porcine endocranium, and then mechanical properties, suture retention strength, and stability were tested. PSR operation was performed on 24 rabbit eyes using treated biological materials. Ophthalmic examination was performed regularly before and after PSR operation (1 week, 1 month, 3 months, 6 months). To evaluate the effectiveness, A ultrasound, diopter, and optical coherence tomography were conducted. General condition, fundus photograph, and pathological examination were recorded to evaluate the safety. Compared with genipin crosslinked bovine pericardium (Gen-BP) (21.29 ± 13.29 Mpa), genipin crosslinked porcine endocranium (Gen-PE) (34.85 ± 3.67 Mpa,P< 0.01) showed a closer elastic modulus to that of genipin crosslinked human sclera. There were no complications or toxic reactions directly related to the materials. Capillary hyperplasia, inflammatory cell infiltration, and collagen fiber deposition were observed, and the content of type I collagen fibers increased after PSR. Overall, the choroidal thickness of treated eyes was significantly thickened at different time points after PSR, which were 96.84 ± 21.08 µm, 96.72 ± 22.00 µm, 90.90 ± 16.57 µm, 97.28 ± 14.74 µm, respectively. The Gen-PE group showed changes that were almost consistent with the overall data. Gen-BP and Gen-PE are safe biological materials for PSR. The Gen-PE group demonstrated more significant advantages over the Gen-BP group in terms of material properties.

Effectiveness and Safety of Different Patch Materials for Supravalvar Aortic Stenosis (Middle-Term Outcomes).

Background: To determine the effectiveness and safety of different patch materials in the treatment of pediatric patients with congenital supravalvular aortic stenosis (SVAS). Methods: 218 consecutive SVAS patients (age < 14 years) who underwent surgery from Beijing Fuwai and Yunnan Fuwai hospital between 2002 and 2020 were included. Patients were divided into the pericardium patch group (133 (61.0%)), modified patch group (43 (19.7%)) and artificial patch group (42 (19.3%)). The primary safety endpoint was patch-related adverse complications (post-operation patch hemorrhage or aortic sinus aneurysm at 2-year follow-up). The primary effectiveness outcome was the re-operation or restenosis at 2-year follow-up. Multivariable cox regression was used to obtain the hazard ratio (HR). Results: The median age at operation was 43.5 months (IQR 24.0-73.0). Only three patients had patch-related adverse complications, and no difference existed among the three groups (p = 0.763). After a median follow-up of 24.0 months (IQR 6.0-48.0), patients with a pericardium patch had a lower re-operation or restenosis rate compared with the other two groups (pericardium patch vs modified patch, HR = 0.30, 95% CI 0.12-0.77; pericardium patch vs artificial patch, HR = 0.33, 95% CI 0.13-0.82), even in the main subgroup and sensitivity analysis. Conclusions: In pediatric patients, the safety of autologous pericardium patch is acceptable, along with lower rates of middle-term re-operation or restenosis. Clinical Trial Registration: http://www.chictr.org.cn, number: ChiCTR2300067851.

Effect of bioprosthetic leaflet anisotropy on stent dynamics of Transcatheter Aortic Valve Replacement devices.

The assessment of stent fatigue in Transcatheter Aortic Valve Replacement (TAVR) systems is critical for the design of next-generation devices, both in vitro and in vivo. The mechanical properties of the bioprosthetic heart valves (BHVs) have a significant impact on the fatigue life of the metallic stent and thus must be taken into consideration when evaluating new TAVR device designs. This study aims to investigate the relationship between BHV anisotropic behaviour and the asymmetric deflections of the stent frame observed during in vitro testing. An explicit dynamics finite element model of the nitinol stent with attached bioprosthetic valve leaflets was developed to evaluate the deflections of the TAVR device under haemodynamic loading. Our results demonstrate that pericardium behaviour plays a dominant role in determining stent frame deflection. The anisotropic behaviour of the leaflets, resulting from collagen fibre orientation, affects the extent of deflection encountered by each commissure of the frame. This leads to asymmetric variation in frame deflection that can influence the overall fatigue life of the nitinol stent. This study highlights the importance of considering both the flexible nature of the metallic stent as well as the leaflet anisotropic behaviour in the design and fatigue assessment of TAVR systems.