Valve Type Research Articles

A Real-Time Intelligent Valve Monitoring Approach through Cameras Based on Computer Vision Methods.

Abnormal valve positions can lead to fluctuations in the process industry, potentially triggering serious accidents. For processes that frequently require operational switching, such as green chemical processes based on renewable energy or biotechnological fermentation processes, this issue becomes even more severe. Despite this risk, many plants still rely on manual inspections to check valve status. The widespread use of cameras in large plants now makes it feasible to monitor valve positions through computer vision technology. This paper proposes a novel real-time valve monitoring approach based on computer vision to detect abnormalities in valve positions. Utilizing an improved network architecture based on YOLO V8, the method performs valve detection and feature recognition. To address the challenge of small, relatively fixed-position valves in the images, a coord attention module is introduced, embedding position information into the feature channels and enhancing the accuracy of valve rotation feature extraction. The valve position is then calculated using a rotation algorithm with the valve's center point and bounding box coordinates, triggering an alarm for valves that exceed a pre-set threshold. The accuracy and generalization ability of the proposed approach are evaluated through experiments on three different types of valves in two industrial scenarios. The results demonstrate that the method meets the accuracy and robustness standards required for real-time valve monitoring in industrial applications.

Differential response to preoperative exercise training in patients candidates to cardiac valve replacement

BackgroundThere is lack of evidence regarding safety, effectiveness and applicability of prehabilitation on cardiac surgery population, particularly in patients candidates to cardiac valve replacement. The aim of the study is to assess and compare the effect of a multimodal prehabilitation program on functional capacity in patients with severe aortic stenosis (AoS) and severe mitral regurgitation (MR) proposed for valve replacement surgery.MethodsSecondary analysis from a randomised controlled trial whose main objective was to analyze the efficacy of a 4–6 weeks multimodal prehabilitation program in cardiac surgery on reducing postoperative complications. For this secondary analysis, only candidates for valve replacement surgery were selected. The primary outcome was the change in endurance time (ET) from baseline to preoperative assessment measured by a cycling constant work-rate cardiopulmonary exercise test.Results68 patients were included in this secondary analysis, 34 (20 AoS and 14 MR) were allocated to the prehabilitation group and 34 (20 AoS and 14 MR) to control group. At baseline, patients with AoS had better left systolic ventricular function and lower prevalence of atrial fibrillation compared to MR (p = 0.022 and p = 0.035 respectively). After prehabilitation program, patients with MR showed greater improvement in ET than AoS patients (101% vs. 66% increase from baseline). No adverse events related to the prehabilitation program were observed.ConclusionsA 4–6 week exercise training program is safe and overall improves functional capacity in patients with severe AoS and MR. However, exercise response is different according to the cardiac valve type disfunction, and further studies are needed to know the factors that predispose some patients to have better training response.Trial registrationThe study has been registered on the Registry of National Institutes of Health ClinicalTrials.gov (NCT03466606) (05/03/2018).

Efficacy and safety of simultaneous combined Zephyr and Spiration valve therapy in patients with advanced pulmonary emphysema

BackgroundEndoscopic lung volume reduction with valves is a minimally invasive treatment strategy for patients with severe pulmonary emphysema. Two valve systems are currently available: Zephyr and Spiration valves. As these can be implanted simultaneously in the same procedure, the question arose as to the effect on lung function, exercise capacity and subjective disease perception after combined valve treatment. MethodsWe conducted a retrospective analysis of 108 patients with combined, simultaneous treatment of Zephyr and Spiration valves. The decision on which and how many valves to implant was based on the individual patient anatomy. Effects on lung function, exercise capacity and atelectasis formation as well as complications were evaluated 90- and 180-days post-treatment (90d-FU and 180d-FU). ResultsAt 90d-FU (n = 90), the mean change was 86.7 ± 183.7 mL for FEV1 and -645.3 ± 1276.5 mL for RV, with responder rates of 39.8 % and 46.5 %, respectively. Complete atelectasis occurred in 16.7 % and partial atelectasis in 25.5 % of patients. Six-minute walking distance increased by 27.00 m [-1.50 – 68.50m]. The rates of pneumothorax (10.2 %) 6 months after treatment were not higher than in randomized controlled trials (RCTs). Likely due to the inclusion of high-risk patients, there was a higher incidence of severe COPD exacerbation (21.3 %) and pneumonia (12.0 %) compared to RCTs. ConclusionsThe combined implantation of Zephyr and Spiration valves resulted in significant clinical and functional improvements with an acceptable risk profile. Therefore, the ability to combine both valve types in severe emphysema could be a promising option in endoscopic lung volume reduction.

Aortic Annular Enlargement versus Isolated Aortic Valve Replacement in Patients with Matched Annulus

We aimed to determine the effect of aortic annular enlargement on the mid-term outcomes of aortic valve replacement surgery by comparing patients with the same-sized (≤23 mm) native aortic annuli. From January 2011 to June 2022, 1,328 patients underwent isolated aortic valve replacement-1,163 without aortic annular enlargement (AVR group) and 165 with aortic annular enlargement (AVR+AAE group). Propensity score matching identified 112 pairs, controlling for native aortic annulus diameter, age, sex, diabetes, chronic lung disease, dialysis, ejection fraction, prior cardiac surgery, indication, hypertension, dyslipidemia, valve type, prior stroke, prior myocardial infarction, and case status. Demographic and preoperative parameters were similar, except body surface area was larger in the AVR+AAE group (2.1 m2 vs 1.9 m2). Median native aortic annulus diameter was 23 mm in both groups. Median prosthesis size was 25 and 23 in the AVR+AAE and AVR groups, respectively. The AVR+AAE group had longer cardiopulmonary bypass (143 vs 111 mins) and cross-clamp (115 vs 82 mins) times. Incidences of perioperative complications including operative mortality (1.8% AVR+AAE vs 3.6% AVR) were similar between groups. 6-year survival was 98% in the AVR+AAE group and 74% in the AVR group (p=0.016). Aortic annular enlargement was an independent protective factor for mid-term mortality with a hazard ratio of 0.19 (p=0.006). The rate of moderate/severe patient-prosthesis mismatch was 19% in the AVR+AAE group and 31% in the AVR group (p=0.16). Patients with small native aortic annuli (≤23 mm) undergoing isolated aortic valve replacement may benefit from aortic annular enlargement.

Von Willebrand Factor Dynamics in Patients with Aortic Stenosis Undergoing Surgical and Transcatheter Valve Replacement.

Aortic stenosis (AS) is a prevalent valvular disorder that poses a significant burden on healthcare systems due to its debilitating symptoms and high mortality rates if left untreated. Surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) are the primary interventions for severe AS, but perioperative complications such as bleeding remain a concern. Von Willebrand factor (VWF), a crucial player in hemostasis, is known to be altered in AS and may contribute to the hemostatic imbalance observed in these patients. This prospective study aimed to investigate the association between prosthetic valve type, size, and postprocedural VWF levels in patients undergoing aortic valve replacement (AVR) for severe AS. This study involved 39 consecutive patients diagnosed with severe AS who underwent SAVR or TAVR. By elucidating the VWF dynamics associated with different prosthetic valves, this study sought to provide valuable insights into personalized valve selection and perioperative management strategies.

Investigation of a newly developed shear built-in valve type MR damper with high damping: Theories and experiments

Magnetorheological (MR) dampers are widely used as semi-active energy-dissipation devices in structural vibration control. Traditional MR dampers, particularly their working mode, often struggle to achieve a high damping force output and sometimes fail to meet the needs of practical engineering. Therefore, it is necessary to study MR dampers that can provide a high damping force. This study proposes an MR damper that combines a built-in shear valve with various working modes of shear extrusion. The damper generates a higher damping force by applying a current to the coils at different positions and altering its working mode. First, the ANSYS Maxwell software simulates the internal magnetic circuit of the damper to assess whether the magnetic field intensity distribution and circuit direction meet the design requirements. Analysis revealed that the internal magnetic circuit distribution was reasonable and satisfied the operating requirements of the damper. Furthermore, the mechanical models of the two working modes were derived based on the Bingham and double-viscous models. Finally, the accuracies of the mechanical models were verified experimentally. The experimental results showed that the simulation values closely matched the experimental values under all the working conditions. Therefore, the proposed mechanical models are reasonable, and can provide significant reference values for practical engineering applications.

Age-Specific Outcomes of Bioprosthetic vs. Mechanical Aortic Valve Replacement: Balancing Reoperation Risk with Anticoagulation Burden.

The choice of prosthesis for aortic valve replacement (AVR) remains challenging. The risk of anticoagulation complications vs. the risk of aortic valve reintervention should be weighed. This study compared the outcomes of bioprosthetic vs. mechanical AVR in patients older and younger than 50. This retrospective study was conducted from 2009 to 2019 and involved 292 adult patients who underwent isolated AVR. The patients were divided according to their age (above 50 years or 50 years and younger) and the type of valves used in each age group. The outcomes of bioprosthetic valves (Groups 1a (>50 years) and 1b (≤50 years)) were compared with those of mechanical valves (Groups 2a (>50 years) and 2b (≤50 years)) in each age group. The groups had nearly equal rates of preexisting comorbidities except for Group 1b, in which the rate of hypertension was greater (32.6% vs. 14.7%; p = 0.025). This group also had higher rates of old stroke (8.7% vs. 0%, p = 0.011) and higher creatinine clearance (127.62 (108.82-150.23) vs. 110.02 (84.87-144.49) mL/min; p = 0.026) than Group 1b. Patients in Group 1a were significantly older than Group 2a (64 (58-71) vs. 58 (54-67) years; p = 0.002). There was no significant difference in the NYHA class between the groups. The preoperative ejection fraction and other echocardiographic parameters did not differ significantly between the groups. Re-exploration for bleeding was more common in patients older than 50 years who underwent mechanical valve replacement (p = 0.021). There was no difference in other postoperative complications between the groups. The groups had no differences in survival, stroke, or bleeding rates. Aortic valve reintervention was significantly greater in patients ≤ 50 years old with bioprosthetic valves. There were no differences between groups in the changes in left ventricular mass, ejection fraction, or peak aortic valve pressure during the 5-year follow-up. The outcomes of mechanical and bioprosthetic valve replacement were comparable in patients older than 50 years. Using bioprosthetic valves in patients younger than 50 years was associated with a greater rate of valve reintervention, with no beneficial effect on the risk of bleeding or stroke.

Epidemiological and microbial trends of infective endocarditis in western Norway: a 7-year prospective observational study

BackgroundIn this prospective, observational study, we aimed to investigate epidemiologic and microbial trends of infective endocarditis in western Norway.MethodsClinical and microbiological characteristics of 497 cases of infective endocarditis from 2016 through 2022 were investigated. Categorical data were analysed using Chi-squared tests. Survival data were analysed using multiple Cox regression and reported using hazard ratios.ResultsThe mean age was 67 years, and 74% were men. The annual incidence rates varied from 10.4 to 14.1 per 100,000 inhabitants per year. Infective endocarditis on native valves was observed in 257 (52%) of the cases, whereas infective endocarditis on prosthetic valves and/or cardiac implantable electronic devices was observed in 240 (48%) of the cases: infection on surgically implanted bioprostheses was observed in 124 (25%) of the patients, infection on transcatheter aortic valve implantation was observed in 47 (10%) patients, and infection on mechanical valves was observed in 34 (7%) cases. Infection related to cardiac implantable electronic devices was observed in a total of 50 (10%) cases.Staphylococcus aureus and viridans streptococci were the most common microbial causes, and isolated in 145 (29%) and 130 (26%) of the cases, respectively.Enterococcal endocarditis showed a rising trend during the study period and constituted 90 (18%) of our total cases of infective endocarditis, and 67%, 47%, and 26% of the cases associated with prosthetic material, transcatheter aortic valve implantation and cardiac implantable electronic devices, respectively.There was no significant difference in 90-day mortality rates between the native valve endocarditis group (12%) and the group with infective endocarditis on prosthetic valves or cardiac implants (14%), p = 0.522. In a model with gender, age, people who inject drugs, microbiology and type of valve affected, only advanced age was significantly associated with fatal outcome within 90 days.ConclusionsThe incidence of infective endocarditis, and particularly enterococcal endocarditis, increased during the study period. Enterococci appeared to have a particular affinity for prosthetic cardiac material. Advanced age was the only independent risk factor for death within 90 days.

Research on the Dual-Objective Scheduling of the Pipeline Path of Liquid Terminal Resources Based on a Hybrid Algorithm

With the daily use of liquid cargoes such as crude oil and their derivatives, the global transportation of liquid cargoes has developed rapidly. Liquid cargoes are mainly transported via tankers and pipelines. In the liquid terminal, the handling operations and internal transportation operations are conducted using oil transfer arms and pipelines, and the pipeline path of the cargo is selected using valves. The number of times a valve opens and closes and the length of pipeline paths are the main factors that affect handling time and cost. In addition, different types of valves have different operating costs and levels of operating energy consumption. At this stage, most of the valve selection work is still manually completed, which consumes a lot of time and generates high labor costs, and the actual operation efficiency is low. In this paper, the cargo unloading pipeline path is the main research object, the problem of oil transfer arms–valves–pipeline (PAVP) is proposed, and a dual-objective model is established, accounting for total time in port and the unloading cost of the vessel. An NSGA-II-Dijkstra hybrid algorithm is employed to solve the PAVP, and the improved algorithm (INIIDA) is designed to improve the solution speed via an adaptive dynamic probability based on the Pareto level and heaps in the shortest path. The results show that the INIIDA could better address the PAVP than the NSGA-II-Dijkstra hybrid algorithm. Innovative fusion algorithms are employed to improve the efficiency of port operations.

Long-Term Outcomes of Mechanical Versus Bioprosthetic Aortic Valve Replacement in Patients Aged Under 50 Years: Meta-Analysis of Reconstructed Time-to-Event Data

To compare the long-term outcomes of mechanical versus bioprosthetic aortic valve replacement (AVR) in patients aged <50 years, we performed a study-level meta-analysis with reconstructed time-to-event data including studies published by December of 2023. The primary outcome was overall survival. Secondary outcomes included reoperation, major bleeding, and stroke. A total of 5 studies met our inclusion criteria, with a total of 4,245 patients (2,311 mechanical and 1,934 bioprosthetic). All studies were observational and the mean age of groups across the studies ranged from 38.2 to 43.0 years. The median follow-up time was 11.4 years (interquartile range 6.9 to 15.0). Bioprosthetic AVR was associated with reduced overall survival and higher risk of all-cause death (hazard ratio [HR] 1.170 95% confidence interval [CI] 1.002 to 1.364, p = 0.046), increased risk of reoperation over time (HR 2.581, 95% CI 2.102 to 3.168, p <0.001), decreased risk of major bleeding (HR 0.500, 95% CI 0.367 to 0.682, p <0.001), and decreased risk of stroke (HR 0.751, 95% C, 0.565 to 0.998, p = 0.049) compared with mechanical AVR in patients aged <50 years. In conclusion, for patients aged <50 years, bioprosthetic AVR is associated with increased mortality and risk of reoperation compared with mechanical valves. In contrast, mechanical AVR is associated with an increased risk of major bleeding events and stroke. These aspects should be carefully considered during the selection of valve type in this age group; however, we should keep in mind that the statistically significant differences in the risk of all-cause death and stroke might not be clinically relevant (because of marginal statistical significance).

Comparing outcomes of balloon-expandable vs. self-expandable valves in transcatheter aortic valve replacement: a systematic review and meta-analysis.

Aortic stenosis (AS) is a common heart condition categorized into congenital and acquired forms. Transcatheter aortic valve replacement (TAVR) is an innovative method for AS management, and two valve types, self-expanding valves (SEV) and balloon-expandable valves (BEV), are used in TAVR. The objective of this study is to compare the clinical outcomes associated with balloon-expandable and self-expandable valves in transcatheter aortic valve replacement. The researchers conducted a comprehensive meta-analysis following PRISMA guidelines and AMSTAR-2 tool. The methodology involved a systematic literature search, strict eligibility criteria, unbiased study selection, meticulous data extraction, quality assessment, and rigorous statistical analysis. Our analysis included twenty-six papers and 26553 patients. BEV exhibited significant advantages over SEV in overall mortality across 21 studies, particularly in perioperative and 30-day assessments. However, no substantial disparities emerged between the two valve types in stroke incidence. BEV demonstrated notable benefits in reducing hospitalization rates across 6 studies and significantly fewer instances of permanent pacemaker implantations across 19 studies, particularly evident in the perioperative setting. Other secondary outcomes like bleeding, acute kidney injury, and myocardial infarction showcased non-significant differences between BEV and SEV. The analysis indicates that BEV may offer benefits in specific aspects of TAVR outcomes, but further research is needed to fully understand the factors influencing patient outcomes and mortality in TAVR procedures.

Differences between valve types in anatomic changes of the aortic root after surgical aortic valve replacement

BackgroundWhen transcatheter aortic valve-in-surgical aortic valve (TAV-in-SAV) is considered as a secondary interventional option, it is desirable to estimate the risk of coronary obstruction during future TAV-in-SAV before the initial surgical aortic valve replacement (SAVR), for which knowledge of the anatomic changes after SAVR is essential. We investigated the changes in the aortic root and evaluated the differences in changes between valve types. MethodsPre- and post-SAVR computed tomography scans of 124 patients with aortic stenosis who underwent SAVR with various bioprosthetic valves were analyzed retrospectively. Postoperative aortic root changes and parameters related to future TAV-in-SAV were compared between the sutured valve group and rapid-deployment/sutureless valve group. ResultsAfter SAVR, the coronary height in the sutured valve group and rapid-deployment/sutureless valve group was shortened by a median of 4.6 to 5.3 mm and 0.5 to 2.2 mm, respectively, and the sinus of Valsalva (SOV) diameter was reduced by a median of 1.6 to 2.7 mm and 0.1 to 1.3 mm, respectively. A significantly higher proportion of patients in the rapid deployment/sutureless valve group had a coronary orifice (especially in the right coronary artery) above the risk plane. The valve-to-coronary distance and valve-to-aorta distance (VTA) were adequate in most patients. The only difference between the groups was in the left VTA. ConclusionsDecreases in coronary height and SOV diameter were observed after SAVR, especially in the sutured valve group. The aortic root structure was better preserved in the rapid-deployment/sutureless valve group. This may be advantageous for future TAV-in-SAV. These results are important for considering the feasibility of future TAV-in-SAV.

Gomphonemavancampianum sp. nov. (Gomphonemataceae, Bacillariophyceae), a new large Gomphonema species from Europe.

During a French biomonitoring survey of the lakes in the region Rhône-Méditerranée-Corse, a large, unknown Gomphonema taxon was observed in a lake in the vicinity of the City of Lyon (Département du Rhône, France), that could not be identified using the currently available literature. Detailed light and scanning electron microscopy investigations revealed the presence of two types of valves, one bearing a thick marginal crest and valves lacking the crest. Following comparison with similar, mostly tropical Gomphonema species, the unknown taxon is described as new: Gomphonemavancampianum sp. nov. Discriminating features of the new species include the peculiar valve shape resembling a Chinese spoon, the broad upper valve part with acuminate tip, the presence of shallow depressions in the axial area, distinctly punctate striae and the occasional presence of the marginal crest. The new species was observed in several samples collected in an oligo- to mesotrophic, calcium-carbonate rich lake with a high ecological quality.

Four-dimensional computed tomography analysis of bicuspid aortic valves

ObjectivesTo evaluate the role of 4-dimensional (4D; 3-dimensional [3D] + time) analysis using multiphase cardiac computed tomography (MCCT) in the description of the aortic annulus (AA) of bicuspid aortic valves (BAV) with regard to the latest expert consensus classification. MethodsElectrocardiography-gated MCCT of 15 patients with BAV were analyzed using in-house software and compared to 15 patients with normal tricuspid aortic valve (TAV). The AA border was pinpointed on 9 reconstructed planes, and the 3D coordinates of the 18 consecutive points were interpolated in 3D using a cubic spline to calculate 3D areas, perimeters, diameters, eccentricity indexes, and global height. Measurements were repeated throughout the cardiac cycle (10 phases). Three additional planes were generated at the level of the left ventricular outflow tract (LVOT), the sinus of Valsalva, and the sinotubular junction. ResultsThe annulus area was significantly larger in BAV compared to TAV (mean indexed 3D area, 5.64 ± 0.84 cm2/m2 vs 4.3 ± 0.38 cm2/m2, respectively; P < .001). The AA was also larger in BAV in terms of perimeter, diameters, and height (P < .001). The Valsalva sinuses and sinotubular junction also were significantly larger in BAV compared to TAV (mean area in end-diastole, 6.06 ± 1.00 cm2 vs 4.69 ± 1.00 cm2 [P < .001] and 5.13 ± 1.62 cm2 vs 3.62 ± 0.99 cm2 [P < .001], respectively). In BAV, 3D AA shape analysis helps distinguish the 3 types of BAV: the 2-sinus type (symmetrical), the fused type, and the partial-fusion type or “form fruste” (both asymmetrical). It also allows determination of the position and height of the nonfunctional commissure. In symmetrical BAV, the nonfunctional commissure was significantly lower than the other commissures (6.01 ± 4.27 mm vs 18.24 ± 3.20 mm vs 17.15 ± 3.60 mm; P < .001), whereas in asymmetrical BAV, the 3 commissures were of comparable height (16.38 ± 0.86 mm vs 15.88 ± 1.69 mm vs 15.37 ± 0.88 mm; P = .316). There was no difference in AA eccentricity indices between TAV and BAV in all phases of the cardiac cycle; however, there was a spectrum of ellipticity for the other components of the aortic root among the different types of valves: going from TAV to asymmetrical BAV to symmetrical BAV, at end-diastole, the LVOT became more circular and the sinuses of Valsalva became more elliptical. Conclusions3D morphometric analysis of the BAV using MCCT allows identification of the type of BAV and the position and height of the nonfunctional commissure. There are significant differences in the morphology of the aortic root between TAV and the different types of BAV. Further studies are needed to evaluate the impact of 3D analysis on the procedural planning for pathologic BAV.

Sex-specific aspects on prognosis after aortic valve replacement for aortic stenosis: a SWEDEHEART registry study

ObjectiveTo compare long-term cardiovascular (CV) outcomes between men and women with aortic stenosis (AS) undergoing aortic valve replacement (AVR) by the type of valve implant.MethodsThe study population consisted of 14...

Age-Based Outcomes After Surgical Aortic Valve Replacement With Bioprosthetic Versus Mechanical Valves

Recommendations for prosthesis type in older patients who underwent surgical aortic valve replacement (SAVR) are established, albeit undervalidated. The purpose of this study is to compare outcomes after bioprosthetic versus mechanical SAVR across various age groups. This was a retrospective study using an institutional SAVR database. All patients who underwent isolated SAVR were compared across valve types and age strata (<65 years, 65 to 75 years, >75 years). Patients who underwent concomitant operations, aortic root interventions, or previous aortic valve replacement were excluded. Objective survival and aortic valve reinterventions were compared. Kaplan-Meier survival estimation and multivariate regression were performed. A total of 1,847 patients underwent SAVR from 2010 to 2023. A total of 1,452 patients (78.6%) received bioprosthetic valves, whereas 395 (21.4%) received mechanical valves. Of those who received bioprosthetic valves, 349 (24.0%) were aged <65 years, 627 (43.2%) were 65 to 75 years, and 476 (32.8%%) were older than 75 years. For patients who received mechanical valves, 308 (78.0%) were aged <65 years, 84 (21.3%) were between 65 and 75 years, and 3 (0.7%) were >75 years. The median follow-up in the total cohort was 6.2 (2.6 to 8.9) years. No statistically significant differences were observed in early-term Kaplan-Meier survival estimates between SAVR valve types in all age groups. However, the cumulative incidence estimates of aortic valve reintervention were significantly higher in patients aged under 65 years who received bioprosthetic than those who received mechanical valves, with 5-year reintervention rates of 5.8% and 3.1%, respectively (p = 0.002). On competing risk analysis for valve reintervention, bioprosthetic valves were significantly associated with an increased hazard of aortic valve reintervention (hazard ratio 3.35, 95% confidence interval 1.73 to 6.49, p <0.001). In conclusion, SAVR with bioprosthetic valves (particularly, in patients aged <65 years) was comparable in survival to mechanical valve SAVR but significantly associated with increased valve reintervention rates.

Self-Expanding Versus Balloon-Expanding Valves 5-Years After Transcatheter Aortic Valve Replacement: Systematic Review and Meta-analysis

Background: With transcatheter aortic valve replacement (TAVR) gaining dominance in the treatment for aortic stenosis, it is crucial to determine which type of valve is most superior long-term. Previous studies have compared shorter term outcomes of the two valves; however, long-term outcomes are yet to be determined. Objectives: This systematic review and meta-analysis evaluate the five-year outcomes of self-expanding valves (SEV), in comparison to balloon-expanding valves (BEV) in an intermediate to high-risk population. Methods: The systematic review and meta-analysis followed the 2020 PRISMA guidelines. Seven online databases (PubMed, Embase, Web Of Science, Scopus, Google Scholar, Cochrane, Rowan-Virtua SOM Library) were screened. 15 studies met the inclusion criteria (10,416 TAVR procedures). Mortality, cardiovascular-related mortality, new pacemaker implantation rates, mean aortic gradient, and aortic regurgitation rates were assessed at five years. Results: A lower mean aortic gradient (p &lt; 0.0006, Cohen’s d = 2.86) throughout SEV procedures, and a lower number of new pacemaker implantation rates (p &lt; 0.0001, Cohen’s d = 0.29) from BEV procedures were analyzed. All other outcomes did not yield significant results. Conclusion: TAVR using either SEV or BEV portrayed similar outcomes, with exception to new pacemaker implantation rates and mean aortic gradient. Using BEV to treat aortic stenosis in an intermediate to high-risk population may lower chances of new pacemaker implantation within 5 years, reducing the need for future procedures and their associated risks. Further studies utilizing RCTs would be beneficial in controlling confounding variables, such as surgeon experience, and patient compliance to postoperative instructions.

Patients with a Bicuspid Aortic Valve (BAV) Diagnosed with ECG-Gated Cardiac Multislice Computed Tomography-Analysis of the Reasons for Referral, Classification of Morphological Phenotypes, Co-Occurring Cardiovascular Abnormalities, and Coronary Artery Stenosis.

Background/Objectives: The aim of this study was to analyze a group of patients with a bicuspid aortic valve (BAV) examined with ECG-gated cardiac CT (ECG-CT), focusing on the assessment of the clinical reasons for cardiac CT, cardiovascular abnormalities coexisting with their BAV, and coronary artery stenosis. Methods: A detailed statistical analysis was conducted on 700 patients with a BAV from a group of 15,670 patients examined with ECG-CT. Results: The incidence of a BAV in ECG-CT was 4.6%. The most common reason for examination was suspicion of coronary heart disease-31.1%. Cardiovascular defects most frequently associated with a BAV were a VSD (4.3%) and coarctation of the aorta (3.6%), while among coronary anomalies, they were high-take-off coronary arteries (6.4%) and paracommissural orifice of coronary arteries (4.4%). The analysis of the coronary artery calcium index showed significantly lower values for type 2 BAV compared to other valve types (p < 0.001), with the lowest average age in this group of patients. Moreover, the presence of a raphe between the coronary and non-coronary cusps was associated with a higher rate of significant coronary stenosis compared to other types of BAVs (p < 0.001). Conclusions: The most common reason for referral for cardiac ECG-CT in the group ≤ 40-year-olds with a BAV was the suspicion of congenital cardiovascular defects, while in the group of over 40-year-olds, it was the suspicion of coronary artery disease. The incidence of cardiovascular abnormalities co-occurring with BAV and diagnosed with ECG-CT differs among specific patient subgroups. The presence of a raphe between the coronary and non-coronary cusps appears to be a potential risk factor for significant coronary stenosis in patients with BAVs.

Savings associated with surgical aortic valve replacement with a RESILIA tissue valve based on seven-year COMMENCE trial results

Background Bioprostheses with RESILIA tissue demonstrate a reduction in calcification and improve health outcomes in pre-clinical and clinical studies. Prior economic analyses which relied on 5 years of evidence from the COMMENCE trial demonstrate financial savings for RESILIA tissue valves relative to mechanical valves after surgical aortic valve replacement (SAVR). Given the recent release of 7-year COMMENCE data, this economic evaluation updates the estimate for long-run savings of bioprosthetic valves with RESILIA. Methods Simulation models estimated disease progression across two hypothetical SAVR cohorts (tissue vs. mechanical) of 10,000 patients each in the US. The primary comparison calculated the SAVR-related expenditures associated with each valve type ($US, 2023). Health outcome probabilities were based on the COMMENCE trial though year 7 and projected for an additional 8 years based on prior studies of tissue and mechanical SAVR. Costs for key outcomes (mortality, reoperation, bleeding, thromboembolism, endocarditis) and anticoagulant monitoring were sourced from the literature. Incidence rates of health outcomes associated with mechanical valves relied on relative risks of tissue valve versus mechanical valve patients. Results Seven-year savings are $13,415 (95% CI = $10,472–$17,321) per patient when comparing RESILIA versus mechanical SAVR. Projected 15-year savings were $23,001 ($US, 2023; 95% CI = $17,802–$30,421). Most of the 15-year savings are primarily attributed to lower anti-coagulation monitoring costs ($21,073 in ACM savings over 15 years), but lower bleeding cost (savings: $2,294) and thromboembolism-related expenditures (savings: $852) also contribute. Reoperation and endocarditis expenditures were slightly larger in the RESILIA cohort. If reoperation relative risk reverts from 1.1 to 2.2 (the level in legacy tissue valves) after year 7, savings are $18,064. RESILIA SAVR also reduce costs relative to legacy tissue valves. Conclusion Patients receiving RESILIA tissue valves are projected to have lower SAVR-related health expenditures relative to mechanical and legacy tissue valves.

Multi-Objective Optimization towards Heat Dissipation Performance of the New Tesla Valve Channels with Partitions in a Liquid-Cooled Plate

The utilization of liquid-cooled plates has been increasingly prevalent within the thermal management of batteries for new energy vehicles. Using Tesla valves as internal flow channels of liquid-cooled plates can improve heat dissipation characteristics. However, conventional Tesla valve flow channels frequently experience challenges such as inconsistencies in heat dissipations and unacceptably high levels of pressure loss. In light of this, this paper proposes a new type of Tesla valve with partitions, which is used as internal channel for liquid-cooled plate. Its purpose is to solve the shortcomings of existing flow channels. Under the working conditions of Reynolds number equal to 1000, the neural network prediction-NSGA-II multi-objective optimization method is used to optimize the channel structural parameters. The objective is to identify the optimal structural configuration that exhibits the greatest Nusselt number while simultaneously exhibiting the lowest Fanning friction factor. The variables to consider are the half of partition thickness H, partition length L, and the fillet radius R. The study result revealed that the optimal parameter combination consisted of H = 0.25 mm, R = 1.253 mm, L = 0.768 mm, which demonstrated the best performance. The Fanning friction factor of the optimized flow channel is substantially reduced compared to the reference channel, reducing by approximately 16.4%. However, the Nusselt number is not noticeably increased, increasing by only 0.9%. This indicates that the optimized structure can notably reduce the fluid’s friction resistance and pressure loss and slightly enhance the heat dissipation characteristics.