Porcine Valve Research Articles

Comparison of Two Generations of Self-Expandable Transcatheter Heart Valves in Nine Surgical Valves: An In Vitro Study.

(1) Background: This study aimed to analyse the hydrodynamic performance of two generations of self-expanding transcatheter heart valves (THV) as a valve-in-valve (ViV) in different surgical aortic valve (SAV) models under standardised conditions. The nitinol-based Evolut R valve is frequently used in ViV procedures. It is unclear whether its successor, the Evolut PRO, is superior in ViV procedures, particularly considering the previously implanted SAV model. (2) Methods: EvolutTM R 26 mm and EvolutTM PRO 26 mm prostheses were implanted in nine 21 mm labelled size SAV models (Hancock® II, Mosaic® UltraTM, EpicTM Supra, TrifectaTM GT, Perimount®, Perimount® Magna Ease, AvalusTM, IntuityTM, Freestyle®) to analyse their hydrodynamic performance under defined circulatory conditions in a pulse duplicator. (3) Results: Both THVs presented with the lowest effective orifice area (EOA) and highest mean pressure gradient (MPG) inside Hancock® II, whereas THVs in Intuity showed the highest EOA and lowest MPG. Evolut R and Evolut PRO showed significant hydrodynamic differences depending on the SAV. Both THVs performed similarly in porcine valves. Although the Evolut R performed better than Evolut PRO in stented bovine SAVs, the Evolut PRO was superior inside the Intuity. Further, the SAV model design markedly influenced the TAV's geometric orifice area and pin-wheeling index. (4) Conclusions: These findings show that the Evolut R and Evolut PRO perform differently depending on the previously implanted SAV model. THV selection for treatment of a specific SAV model should consider these results.

Ten-Year Follow-Up of Mitral Valve Replacement With the Epic Porcine Valve in a Medicare Population

BackgroundBioprosthetic surgical mitral valve replacement (SMVR) remains an important treatment option in the era of transcatheter valve interventions. This study presents 10-year clinical outcomes of Medicare beneficiaries who underwent SMVR with a contemporary low-profile mitral porcine valve. MethodsThis was a single-arm observational study using Medicare fee-for-service claims data. Deidentified patients undergoing SMVR with the Epic mitral valve (Abbott) in the United States between January 1, 2008 and December 31, 2019 were selected by International Classification of Diseases, Ninth and Tenth Revision procedure codes and then linked to a manufacturer device tracking database. All-cause mortality, heart failure (HF) rehospitalization, and mitral valve reintervention (surgical or transcatheter valve-in-valve) were evaluated at 10 years by using the Kaplan-Meier method. ResultsAmong 75,739 Medicare beneficiaries undergoing SMVR during the study period, 14,015 received the Epic mitral valve (Abbott), 76.5% (10,720) of whom had underlying HF. The mean age was 74 ± 8 years. Survival at 10 years in patients without preoperative HF was 40.4% (95% CI, 37.4%-43.4%) compared with 25.4% (95% CI ,23.8%-27.0%) for patients with HF (P < .001). The 10-year freedom from HF rehospitalization was 51.3% (95% CI, 49.4%-53.1%). Freedom from mitral valve reintervention was 91.4% (95% CI, 89.7%-92.7%) at 10 years. ConclusionsThis real-world nationwide study of Medicare beneficiaries receiving the Epic mitral valve demonstrates >90% freedom from all-cause valve reintervention and >50% freedom from HF rehospitalization at 10 years after implantation. Long-term survival and HF rehospitalization in this population with mitral valve disease treated with SMVR was found to be affected by underlying HF.

Characteristic calcification behavior of five surgical aortic valve bioprostheses models: An in vitro study.

The durability of surgical aortic valve bioprostheses (SAV) is limited by the calcification of the leaflets, which results in degeneration. In clinical routine, there seems to be substantial variability in the degeneration of specific SAV models. Our study aims to establish an in vitro calcification model for prosthetic valves,characterizing the calcification behavior of different SAVs. Five commercially available SAV models (Epic™ Supra, Freestyle®, Intuity®, Perimount®, and Trifecta™) were perfused with double-distilled water and physiological buffer with a defined calcium concentration (CaCl2 = 1.5 mM) at 37°C over 32.9 million cycles in a Hi-Cycle tester which corresponds to approximately 1 patient-year (calcified group). Untreated prosthetic valves served as the negative control group (noncalcified group). Calcium titration, scanning electron microscopy (SEM), histological examination, and tissue thickness measurements were performed to evaluate noncalcified and calcified SAVs (n = 10). Treatment in the Hi-Cycle tester with calcification buffer maintained significantly higher calcium absorption of SAVs compared to the control group (p < 0.001). Additionally, hydroxyapatite crystals were found in the calcified SAV in SEM. Porcine valves rarely demonstrated punctual calcification pattern, while bovine pericardial valves presented distinct planar calcification pattern in histological examination. Further, calcification content differed significantly depending on the SAV model, with the highest calcium content in Trifecta (213 µg/cm2) and the lowest in Epic Supra (8 µg/cm2) (p < 0.001). Data from our study revealed significant differences in leaflet calcification for the various aortic valve bioprostheses models. Further studies are necessary to investigate whether these findings can mimic the clinical data of the implanted prostheses.

Durability of porcine and pericardial prostheses in tricuspid valve replacement

ObjectiveBiologic valves dominate tricuspid valve replacement, yet data on different valve types are lacking. We compare the survival and durability of porcine and pericardial tricuspid prostheses. MethodsA retrospective review of consecutive patients undergoing tricuspid valve replacement with porcine (N = 542) or pericardial (N = 144) prostheses between 1975 and 2022 was performed using a prospectively maintained institutional database. Concurrent procedures were included. Cox proportional hazards and logistic regression were performed. ResultsPatients who received the porcine prosthesis, compared with pericardial, were younger (56 ± 17 years vs 63 ± 15 years) and more likely to present urgently (55% porcine, 44% pericardial); however, there were no differences in redo status or concomitant operations. Ten-year survival was not significantly different between the porcine and pericardial groups (35% ± 3% vs 28% ± 4%, respectively, P = .2). The 10-year cumulative incidence of structural valve deterioration (porcine 9% ± 2%, pericardial 11% ± 3%, P = .8), reoperation for structural valve deterioration (porcine 5% ± 1%, pericardial 4% ± 2%, P = .06), and severe regurgitation (porcine 4% ± 1%, pericardial 5% ± 2%, P = .7) were not significantly different between groups. The failure mode was similar, with no difference in severe stenosis (porcine 32/47 [68%], pericardial 11/16 [69%], P = .9) or severe regurgitation (porcine 18/47 [38%], pericardial 7/16 [44%], P = .7). On regression analysis, valve type was not associated with survival (P = .6). Valve type was not associated with structural valve deterioration (P = .1) or reoperation for structural valve deterioration (P = .9). ConclusionsIn our series, there were no differences in survival or durability between porcine and pericardial valves. In most patients undergoing tricuspid valve replacement, the choice of porcine versus pericardial prosthesis is unlikely to affect clinical outcomes.

Restricted cusp motion in newly implanted tricuspid bioprostheses: Incidence, predictors, and impact on survival

ObjectiveTo investigate the occurrence of restricted cusp motion (RCM) at the time of bioprosthetic tricuspid valve replacement (TVR) and analyze associated risk factors and outcomes. MethodsThis study involved adult patients who underwent TVR with a bioprosthesis at our institution between 2012 and 2022. Bioprosthetic cusp motion was analyzed de novo through a detailed review of intraoperative transesophageal echocardiograms (TEE). Two models of porcine valves were implanted: the Medtronic Hancock II bioprosthesis and the St Jude Medical Epic bioprosthesis. ResultsAmong the 476 patients who met the inclusion criteria, RCM was identified on immediate post-bypass TEE in 150 (31.5%); there was complete immobility of the cusp in 63 patients (13.2%) and limited movement of a cusp in 87 patients (18.3%). In a multivariable logistic regression analysis, the Hancock II model (odds ratio [OR], 6.15; P < .001), a larger orifice area (per IQR increase: OR, 1.58; P = .017), a smaller body surface area (per IQR increase: OR, .68; P = .040), and a lower ejection fraction (per IQR increase: OR, .60; P = .033) were independently associated with having RCM. Cox regression adjusting for 15 covariates revealed that RCM at the time of TVR was independently associated with an increased risk of mortality (hazard ratio, 1.35; P = .049). ConclusionsThis study revealed a high incidence of RCM in bioprosthetic valves in the tricuspid position detected shortly postimplantation, which was associated with increased late mortality. To reduce the probability of RCM, it is important to select the appropriate prosthesis model and size, particularly in small patients.

Long-Term Outcomes of Bioprosthetic Valves in the Mitral Position: A Pooled Meta-Analysis of Reconstructed Time-to-Event Individual Patient Data

ObjectivesBioprosthetic MVR use is on the rise, but data regarding long term durability is lacking. We sought to perform a reconstructed individual patient data meta-analysis from published Kaplan Meier curves to ascertain survival, freedom from valve degeneration and reoperation in studies published since 2010. We explored the effects of age and valve type (bovine pericardial or porcine valve) on outcomes. MethodsWe searched MEDLINE, OVID, Embase and Cochrane CENTRAL for studies reporting at least 3 years of follow-up after bMVR and published since 2010. The ROBINS-I tool was used to assess methodological quality. Kaplan Meier curves were digitized to extract individual patient data and reconstructed estimates for overall survival, freedom from SVD and freedom from re-operation. Results20 studies (16465 patients) were included. 9 studies reported on porcine valves, 6 on bovine and 7 did not specify the valve type. Overall survival after bMVR at 15 years was 40% (CI 38%-42%), freedom from re-operation at 15 years was 79% (CI 76%-82%) and freedom from structural valve degeneration at 15 years was 64% (58%-70%). Freedom from SVD was improved in the 70+ age group (93% up to 25 years, HR 6.6(2.5-17) for 18-59 VS >70, p<0.0001). There was no difference in valve durability or survival between bovine pericardial or porcine valves. ConclusionIn this meta-analysis patients of receiving bioprosthetic mitral valve replacement using newer generation valves, the inverse relationship between age and SVD was re-iterated in the 70+ age group. Prosthesis type made no difference in outcomes.

Late Outcomes of Porcine and Pericardial Bioprostheses After Mitral Valve Replacement in 1162 Patients

BackgroundDebate continues regarding the superiority of porcine vs pericardial bioprostheses, and data relevant to this comparison are scant. This study compared late survival and structural valve deterioration of porcine and pericardial mitral valve prostheses. MethodsAdults undergoing mitral valve replacement with 1 first-generation porcine valve model and 1 pericardial valve line were reviewed from a prospectively maintained institutional database between 1976 and 2020. Multivariable regression and Cox proportional hazards analysis were used to compare late outcomes. ResultsOf 1162 consecutive patients, 612 (53%) received porcine valves and 550 (47%) received pericardial valves. At 10 years, patient survival (porcine, 36% ± 2%; pericardial, 38% ± 3%; P = .5) and cumulative incidence of mitral valve structural deterioration (porcine, 18% ± 2%; pericardial, 19% ± 3%; P = .3) were similar. The structural failure mode was more likely severe mitral stenosis in pericardial valves (35 of 50 [70%] vs 38 of 106 [36%]; P < .001), and it was more likely severe mitral regurgitation in porcine valves (80 of 106 [75%] vs 19 of 50 [38%]; P < .0001). After adjustment, structural deterioration was associated with younger patient age (P < .001) but not valve type. At 10 years, porcine valves demonstrated a higher cumulative incidence of mitral reoperation (19% ± 2% vs 9% ± 2%; P < .001) and reoperation for structural deterioration (15% ± 1% vs 6% ± 2%; P = .007). ConclusionsThis study demonstrated similar rates of 10-year survival and structural deterioration with porcine and pericardial bioprostheses in mitral valve replacement. The study suggests a lack of major improvement in durability of mitral bioprosthetic valves over time. The failure mode may have a greater influence on surgeon decision making regarding valve choice.

Shear Stress Quantification in Tissue Engineering Bioreactor Heart Valves: A Computational Approach.

Tissue-engineered heart valves can grow, repair, and remodel after implantation, presenting a more favorable long-term solution compared to mechanical and porcine valves. Achieving functional engineered valve tissue requires the maturation of human cells seeded onto valve scaffolds under favorable growth conditions in bioreactors. The mechanical stress and strain on developing valve tissue caused by different pressure and flow conditions in bioreactors are currently unknown. The aim of this study is to quantify the wall shear stress (WSS) magnitude in heart valve prostheses under different valve geometries and bioreactor flow rates. To achieve this, this study used fluid-structure interaction simulations to obtain the valve's opening geometries during the systolic phase. These geometries were then used in computational fluid dynamics simulations with refined near-wall mesh elements and ranges of prescribed inlet flow rates. The data obtained included histograms and regression curves that characterized the distribution, peak, and median WSS for various flow rates and valve opening configurations. This study also found that the upper region of the valve near the commissures experienced higher WSS magnitudes than the rest of the valve.

A tissue-silicone integrated simulator for right ventricular pulsatile circulation with severe functional tricuspid regurgitation

There is a great demand for development of a functional tricuspid regurgitation (FTR) model for accelerating development and preclinical study of tricuspid interventional repair devices. This study aimed to develop a severe FTR model by creating a tissue-silicone integrated right ventricular pulsatile circulatory simulator. The simulator incorporates the porcine tricuspid annulus, valve leaflets, chordae tendineae, papillary muscles, and right ventricular wall as one continuous piece of tissue, thereby preserving essential anatomical relationships of the tricuspid valve (TV) complex. We dilated the TV annulus with collagenolytic enzymes under applying stepwise dilation, and successfully achieved a severe FTR model with a regurgitant volume of 45 ± 9 mL/beat and a flow jet area of 15.8 ± 2.3 cm2 (n = 6). Compared to a normal model, the severe FTR model exhibited a larger annular circumference (133.1 ± 8.2 mm vs. 115.7 ± 5.5 mm; p = 0.009) and lower coaptation height (6.6 ± 1.0 mm vs. 17.7 ± 1.3 mm; p = 0.003). Following the De-Vega annular augmentation procedure to the severe FTR model, a significant reduction in regurgitant volume and flow jet area were observed. This severe FTR model may open new avenues for the development and evaluation of transcatheter TV devices.

Long-Term Survival Benefits of Porcine versus Pericardial Bioprostheses in Elderly Patients Undergoing Isolated Aortic Valve Replacement: A 32-Year Study.

The elderly population is growing at an unprecedented rate. Aortic valve disease increases with age. Bioprostheses are the valves of choice for older patients; however, the optimal tissue valve remains undetermined. The purpose of this investigation was to perform a life-of-patient survival comparison of the prototypical porcine and pericardial prostheses in elderly patients. The study population (N = 1480) consisted of patients 65 years of age and older who underwent isolated aortic valve replacement from 1990 through 2005 with a Carpentier-Edwards Porcine (n = 650) or Pericardial (n = 830) bioprosthesis. Propensity score-matched groups were created. Valve selection was not associated with operative mortality. Survival estimates at 10 years were better for Pericardial (41.8%; 95% CI: 37.9 to 45.7) than Porcine (32.6%; 95% CI: 28.8 to 36.3); and 5.2% (95% CI: 3.2 to 7.1) versus 2.0%; (95% CI: 0.8 to 3.2) at 20 years (p < 0.001). E-value analysis found minimal influence of unknown study confounders. Factors associated with long-term mortality were porcine valve (p < 0.001), age (p < 0.001), diabetes mellitus (p < 0.001), preop renal insufficiency (p < 0.001), peripheral artery disease (p = 0.011), congestive heart failure (p = 0.003), New York Heart Association Class III or IV (p = 0.004), surgical history-reoperation (p = 0.012), transient ischemic attack (p = 0.009), prolonged ventilation (p = 0.010), postop renal insufficiency (p < 0.001), and atrial fibrillation (p = 0.009). The indexed Effective Orifice Area (EOAi) was assessed and did not influence observed long-term survival differences. This unusual lifetime study provided substantial evidence for the superiority of the pericardial over the porcine bioprosthesis in the aortic position in elderly patients. It demonstrated enhanced long-term survival benefits for elderly patients without any increase in perioperative mortality. It is intended to inform future investigation into aortic valve design.

Strengthened Decellularized Porcine Valves via Polyvinyl Alcohol as a Template Improving Processability.

The heart valve is crucial for the human body, which directly affects the efficiency of blood transport and the normal functioning of all organs. Generally, decellularization is one method of tissue-engineered heart valve (TEHV), which can deteriorate the mechanical properties and eliminate allograft immunogenicity. In this study, removable polyvinyl alcohol (PVA) is used to encapsulate decellularized porcine heart valves (DHVs) as a dynamic template to improve the processability of DHVs, such as suturing. Mechanical tests show that the strength and elastic modulus of DHVs treated with different concentrations of PVA significantly improve. Without the PVA layer, the valve would shift during suture puncture and not achieve the desired suture result. The in vitro results indicate that decellularized valves treated with PVA can sustain the adhesion and growth of human umbilical vein endothelial cells (HUVECs). All results above show that the DHVs treated with water-soluble PVA have good mechanical properties and cytocompatibility to ensure post-treatment. On this basis, the improved processability of DHV treated with PVA enables a new paradigm for the manufacturing of scaffolds, making it easy to apply.

Porcine or Bovine Tissue Valves: Which are Better for Surgical Aortic Valve Replacement?

Summary The choice between mechanical and bioprosthetic aortic valve implants is affected by relatively clear criteria. However, the choice between porcine or pericardial valve is more complex regarding bioprosthetic devices. We aimed to elucidate any hemodynamic and clinical difference between two widely used bioprosthetic valves: the Sorin Mitroflow bovine pericardial valve and the St. Jude Medical Epic Supra porcine valve. We retrospectively studied 71 consecutive patients separated into two groups based on the valve they received. Clinical outcomes included patient survival and hemodynamic performance of the implanted prostheses. Patients were assessed at one and five years postoperatively. Mean transprosthetic pressure gradients were used as a marker of hemodynamic performance. The Mitroflow valve exhibited lesser mean transvalvular gradients than the Epic valve for all labelled sizes at one and five years postoperatively. The 5-year survival was equal between groups. Both prostheses demonstrated a small but significant increase in mean pressure gradients in the fifth year. Most patients enjoyed significant clinical improvement as assessed by NYHA functional class. Both bioprostheses performed very well with excellent hemodynamic parameters. The pericardial valves are a safe and appropriate choice for surgical bioprosthetic aortic valve replacement.

Bovine pericardial versus porcine bioprosthetic aortic valves: A nationwide population-based cohort study in Korea

ObjectiveTo compare the clinical outcomes of aortic valve replacement (AVR) using bovine pericardial and porcine bioprostheses, utilizing a nationwide administrative claims database. MethodsAdult patients (age ≥40 years) who underwent bioprosthetic AVR, without other valve replacements, between 2003 and 2018 were identified from the Korean National Health Insurance Service database. The outcomes of interest were all-cause mortality, cardiac mortality, and valve-related events, including the incidence of reoperation, endocarditis, systemic thromboembolism, and major bleeding. Baseline adjustment was performed using propensity score matching. Time-related outcomes were evaluated using a competing risk analysis, with death as a competing risk. ResultsAmong the 7714 patients who underwent bioprosthetic AVR, 5621 (72.9%) received bovine pericardial prostheses and 2093 (27.1%) received porcine bioprostheses. After matching, 1937 pairs were included in the final analysis. During follow-up (median, 4.49 years; interquartile range, 2.83-8.20 years), the use of porcine bioprostheses was associated with a higher risk of aortic valve reoperation (adjusted hazard ratio [HR], 1.87; 95% confidence interval [CI], 1.16 to 3.01); however, no significant differences were observed in cumulative incidences of all-cause mortality, cardiac mortality, thromboembolism, or major bleeding. Subgroup analyses revealed that the use of bovine valves was associated with improved survival in patients with diabetes mellitus, whereas in patients undergoing dialysis, porcine valves exhibited better survival than bovine valves. ConclusionsIn this large nationwide cohort study of patients undergoing bioprosthetic aortic valve replacement, the use of porcine prostheses was significantly associated with an increased risk of reoperation compared with the use of bovine prostheses, supporting previous findings.

Comparative anatomy of the mitral valve in four species (human, ovine, porcine and canine): A pre-clinical perspective.

This study aimed to provide comparative anatomical data on the mitral valve and to substantiate the choice between large species for pre-clinical testing of cardiac devices. Different anatomical parameters of the anterior and posterior leaflets, chordae and papillary muscles were measured to characterize the anatomy of the mitral valve in 10 individuals for each four species. Ratios were calculated and used to circumvent the interspecies variations of body and heart size and weight. The results underline many relevant anatomical similarities and differences between man and the three animal species. We confirm that the porcine species is a better model based on anatomical measurements. But many parameters should be considered depending on the shape, size and purpose of the device. The mitral and aortic valve are closer than in man leading to potential damage of the aortic valve by a mitral device. The ovine mitral annulus is more flattened and would sustain more mechanical forces on a round-shaped stent. The anterior and posterior leaflets have comparable height in the animal species leading to more space for implantation. The porcine valve has more chordae allowing less space around the valve for a transcatheter stent. Our observations introduce new comparative data in the perspective of the choice of a large animal model for pre-clinical testing of mitral devices. They are very helpful for all cardiologists, surgeons or engineers who need to understand the reasons for success or failure of a device and to have key elements of discussion.

Long-Term Outcomes of Bovine versus Porcine Mitral Valve Replacement: A Multicenter Analysis.

Recent national guidelines recommending mitral valve replacement (MVR) for severe secondary mitral regurgitation have resulted in an increased utilization of mitral bioprosthesis. There is a paucity of data on how longitudinal clinical outcomes vary by prosthesis type. We examined long-term survival and risk of reoperation between patients having bovine vs. porcine MVR. Study Design. A retrospective analysis of MVR or MVR + coronary artery bypass graft (CABG) from 2001 to 2017 among seven hospitals reporting to a prospectively maintained clinical registry was conducted. The analytic cohort included 1,284 patients undergoing MVR (801 bovine and 483 porcine). Baseline comorbidities were balanced using 1 : 1 propensity score matching with 432 patients in each group. The primary end point was all-cause mortality. Secondary end points included in-hospital morbidity, 30-day mortality, length of stay, and risk of reoperation. In the overall cohort, patients receiving porcine valves were more likely to have diabetes (19% bovine vs. 29% porcine; p < 0.001), COPD (20% bovine vs. 27% porcine; p=0.008), dialysis or creatinine >2 mg/dL (4% bovine vs. 7% porcine; p=0.03), and coronary artery disease (65% bovine vs. 77% porcine; p < 0.001). There was no difference in stroke, acute kidney injury, mediastinitis, pneumonia, length of stay, in-hospital morbidity, or 30-day mortality. In the overall cohort, there was a difference in long-term survival (porcine HR 1.17 (95% CI: 1.00-1.37; p=050)). However, there was no difference in reoperation (porcine HR 0.56 (95% CI: 0.23-1.32; p=0.185)). In the propensity-matched cohort, patients were matched on all baseline characteristics. There was no difference in postoperative complications or in-hospital morbidity and 30-day mortality. After 1 : 1 propensity score matching, there was no difference in long-term survival (porcine HR 0.97 (95% CI: 0.81-1.17; p=0.756)) or risk of reoperation (porcine HR 0.54 (95% CI: 0.20-1.47; p=0.225)). In this multicenter analysis of patients undergoing bioprosthetic MVR, there was no difference in perioperative complications and risk of reoperation of long-term survival after matching.

Human and porcine aortic valve endothelial and interstitial cell isolation and characterization.

Calcific aortic valve stenosis (AVS) is defined by pathological changes in the aortic valve (AV) and their predominant cell types: valvular interstitial (VICs) and endothelial cells (VECs). Understanding the cellular and molecular mechanisms of this disease is a prerequisite to identify potential pharmacological treatment strategies. In this study, we present a unique aortic valve cell isolation technique to acquire specific human and porcine cell populations and compared VICs and VECs of these species with each other for the first time. AV cells were isolated from tissue obtained from human patients undergoing surgical aortic valve replacement (SAVR) or from porcine hearts. Functional analysis and in vitro experiments revealed that endothelial-to-mesenchymal transition (EndMT) can be induced in hVECs, leading to a significant increase in mesenchymal markers. In vitro calcification experiments of VICs demonstrated pronounced expression of calcification markers and visible calcific deposits in Alizarin Red staining in both species after incubation with pro-calcific media. Cells isolated from patient-derived AVs showed mesenchymal and endothelial-specific gene signatures (VIC and VEC, respectively). For instance, von Willebrand factor (vWF) and platelet endothelial adhesion molecule-1 (PECAM1) were upregulated in VECs, while the myofibroblastic markers alpha-smooth muscle actin (α-SMA) and vimentin (VIM) were downregulated in VECs compared to VICs. Analysis of cell function by migration revealed that VECs are more migratory than VICs. Induction of EndMT in vitro in VECs displayed increased expression of EndMT markers and decreased expression of endothelial markers, confirming their mesenchymal transdifferentiation ability. In vitro calcification of VICs revealed upregulation of alkaline phosphatase (ALPL), a hallmark of calcification. In addition, other calcification-related genes such as osteocalcin (BGLAP) and runt-related factor 2 (RUNX2) were upregulated. Alizarin red staining of calcified cells provided a further layer of confirmation that the isolated cells were VICs with osteoblastic differentiation capacity. This study aims to take a first step towards standardizing a reproducible isolation technique for specific human and porcine VEC and VIC populations. A comparison of human and porcine aortic valve cells demonstrated that porcine cells may serve as an alternative cellular model system in settings where human tissue is difficult to obtain.

Morphology and Morphometry of Aortic Valve in Humans and Porcines – A Comparative Study

Background: The aortic valve is a semilunar valve with three leaflets that are in the left ventricle’s outflow tract and only permits unidirectional blood flow away from the ventricle. The valve leaflet can tolerate extremely high mechanical and hemodynamic forces resulting from the great complexity and complicated cellular and molecular functions. Aims: The aim of the study is to provide an add-on to the understanding of the morphological and morphometrical aspects of human and porcine aortic heart valves on comparative grounds so that they can be used as a guide in the construction of three-dimensional (3D)-printed mechanical valve. Materials and Methods: Twenty swine and twenty human hearts were compared and examined in this investigation. The porcine and human hearts weighing in between 300 g and 450 g were considered, and any variation from the normal and any mechanical damage rendered during procurement were all excluded from the study. Results: The length of the attached margin of the right coronary cusp, left coronary cusp, and noncoronary cusp of human and porcine were 45.15 mm, 36.47 mm, and 41.53 mm and 36.55 mm, 43.14 mm, and 36.10 mm, respectively. The length of the free margin and the height of the cusps from nadir to the sinotubular junction and the effective height of the cusp from nadir to the free margin of the cusps of human and porcine have been compared. Conclusion: The human and swine aortic valves share morphological and morphometrical characteristics, which can be used to create 3D valves and tissue engineering procedures with greater biocompatibility and biofunctionality.

Commentary on bovine pericardial versus porcine bioprosthetic mitral valves: results from a Korean Nationwide Cohort Study.

Commentary on bovine pericardial versus porcine bioprosthetic mitral valves: results from a Korean Nationwide Cohort Study.

Bovine pericardial versus porcine bioprosthetic mitral valves: results from a Korean Nationwide Cohort Study.

Comparisons of long-term clinical outcomes of mitral valve replacement (MVR) between bovine pericardial and porcine bioprostheses are conflicting, with limited research in large-scale real-world clinical settings. This study examined clinical outcomes in MVR according to bioprosthesis type using a national administrative claims database. This study included adult patients undergoing bioprosthetic MVR between 2003 and 2018 using administrative health care data from the Korean National Health Insurance Service database. Propensity score matching with competing risk analysis was used to compare the clinical outcomes according to the type of bioprosthesis. The end points were death, cardiac death, and valve-related events, including the incidence of reoperation, endocarditis, systemic thromboembolism, and major bleeding. A total of 3151 patients underwent bioprosthetic MVR with bovine pericardial (n = 1628, 51.7%) or porcine (n = 1523, 48.3%) bioprostheses. After matching, 1170 pairs were included in the final analysis. During follow-up (median 4.49 years, interquartile range 1.87 -8.75 years), death occurred in 1178 patients (6.8%/patient-year), comprising 730 (4.3%/patient-year) cardiac death. No significant differences were noted between the bovine and porcine groups in the cumulative incidences of death from any cause [adjusted hazard ratio (aHR), 1.00; 95% confidence interval (CI), 0.87-1.14], cardiac mortality (aHR, 0.96; 95% CI, 0.81-1.14), or reoperation (aHR, 1.01; 95% CI, 0.72-1.41). This study on a nationwide comparison between bovine and porcine bioprostheses in MVR found no significant differences in clinical outcomes including mortality, and valve-related reoperation.

Long-term clinical outcomes of tricuspid valve replacement using bovine versus porcine valves: a nationwide population-based study.

The early and long-term clinical outcomes of bovine versus porcine tricuspid valve replacement (TVR) were compared based on the nationwide database from the National Health Insurance Service. Of 1464 patients who underwent TVR from 2002 to 2018 in Korea, 541 were enrolled after excluding mechanical TVR, re-TVR, complex congenital heart disease, Ebstein anomaly and age <19 years at operation. Bovine (group B) and porcine valves (group P) were used in 342 and 199 patients, respectively. The median follow-up duration was 4.1 years [interquartile range 1.2-9.0]. Inverse probability of treatment weighting analysis was performed for adjustment between the groups. Early and long-term clinical outcomes, including all-cause mortality, ischaemic stroke, haemorrhagic stroke, endocarditis and reoperation, were compared. In inverse probability of treatment weighting analysis, operative mortality and early clinical outcomes were comparable between the groups. The cumulative incidence of all-cause mortality demonstrated no significant differences between the groups [36.8% vs 38.0% at 5 years in group B versus group P; adjusted hazard ratio = 0.93; P = 0.617]. The cumulative incidence of cardiac death, ischaemic stroke, haemorrhagic stroke and endocarditis also demonstrated no significant differences between the groups (28.1% vs 25.9%, 7.1% vs 1.2%, 3.2% vs 4.2% and 9.7% vs 6.0% at 5 years in group B versus group P, respectively). However, the cumulative incidence of reoperation was higher in group B than in group P (20.2% vs 3.4% at 5 years in group B vs group P; adjusted hazard ratio = 4.76; P = 0.006). Early clinical outcomes and long-term outcomes, including all-cause mortality, cardiac death, ischaemic stroke, haemorrhagic stroke and endocarditis, were comparable between bovine and porcine TVRs. However, porcine valves demonstrated a lower cumulative incidence of reoperation than bovine valves.