Valve Performance Research Articles

Long-Term Durability of Transcatheter Aortic Valve Implantation With Self-Expandable Valve System (from a Real-World Registry)

As transcatheter aortic valve Implantation (TAVI) moves to younger and lower risk patients with longer life expectancy, the long-term durability of TAVI is becoming an increasingly relevant issue. We sought to evaluate the long-term clinical outcome and prosthesis performance of the CoreValve self-expandable valve. Clinical registry of 182 patients consecutively treated with TAVI in a tertiary center from January 2009 to July 2017. Of these, 111 died during an average follow-up (FU) of 1,026 ± 812 days (median IQR: 745, 477 to 1,400 days; longest survival 11 years; 61% mortality at Kaplan-Meier analysis). At 1 month, functional profile improved in all survivors, with 93.9% of them achieving NYHA class I or II. At Cox analysis, the Society of Thoracic Surgeons score (HR: 1.55; p = 0.001), left ventricular ejection fraction <40% (HR: 1.65; p = 0.017) and incident acute kidney injury (HR: 1.96; p = 0.001) were independently associated with all-cause mortality. During FU, echocardiographically assessed mean transprosthetic aortic gradient remained substantially unchanged (from 9.0 ± 2.7 after TAVI to 9.0 ± 5.0 mm Hg at FU; p >0.05). Most patients had none and/or trivial (34%), or mild (58%), fewer had moderate (8%) and none had severe perivalvular leak, without significant change during FU. At 11 years, cumulative incidence of bioprosthetic valve failure and moderate structural valve deterioration (SVD) were 2.9% (95% CI 0.8% to 10%) and 9.3% (95% CI 3.3% to 26.7%), respectively. In conclusion, our registry confirmed that TAVI with the self-expandable CoreValve system was associated with favorable long-term clinical outcomes, with a reassuring low rate of significant bioprosthetic valve failure and moderate SVD.

Analysis of Double Seat Seal of Ultra High Pressure Flat Gate Valve

As an important part of the Christmas tree, the sealing performance of the flat gate valve is very important, and the O-ring seal is the most commonly used seal in the flat gate valve. Therefore, the research on O-rings is particularly important. For the flat gate valve with a single gate, its structure has gradually developed from a single seat seal to a double seat seal. This article mainly analyzes the sealing principle of the double seat in the ultra-high pressure flat gate valve and the influence of the pre-tightening force of the sealing ring on the sealing effect. Using finite element analysis software, a two-dimensional axisymmetric model of the double valve seat sealing structure was established to study the non-metallic sealing performance of the valve seat. The Mises stress, the maximum contact stress of the sealing surface, and the contact area of the sealing surface of the O-ring seal under different compression ratios are analyzed. The results show that when only the sealing performance and pre-tightening force requirements are considered, an O-ring with a larger wire diameter should be selected as much as possible. When considering the service life of the O-ring seal, the compression rate of the seal ring should not exceed 20%. Therefore, the selected seal ring wire diameter is 3.75mm within the recommended seal ring compression rate range.

Study on Shear Fracture Performance of Subsea Test Tree Under Emergency Conditions in the Deepwater Oil and Gas Completion Testing

In order to study the performance variation rule of shear coiled tubing or wireline of SSTT ball valve under different work conditions and different structural parameters. In this study, a numerical simulation method is used to establish a ball valve shear model to calculated the shear process of different working conditions, such as torque, coiled tubing tension, shear velocity and different thickness of coiled tubing under given parameters. The calculated results of the numerical simulation model are in good agreement with the experimental results in the laboratory, which verifies the accuracy of the numerical simulation model of the shear continuous coiled tubing of ball valve mechanism. Based on this model, the failure state and stress state of the ball valve are further studied. This study presents an optimization method to improve the shear fracture performance of ball valves. In order to further evaluate the shear performance of the SSTT, the finite element analysis (FEA) method was used to analyze the influence of single variable or combination variable on the shear force. This study has important guiding significance for the optimal design and application operation on the shearing mechanism of ball valve in the SSTT.

Research on the Reliability of the Operating Performance of the Relief Valve of Nuclear Power Plant under Seismic Conditions

Nowadays, environmental and energy problems are becoming increasingly prominent. Nuclear power plants are an important means to solve these two problems. Therefore, research on the reliability of nuclear power plants is closely related to environmental and energy issues. The reliability research of nuclear safety valves has always been the top priority in the reliability research of nuclear power plants, so the reliability of the operation performance of such relief valves must be considered under seismic conditions. This article borrows ANSYS to carry out fluid-solid coupling simulation of relief valves, including simulations under seismic conditions and non-seismic conditions, and explores changes during opening and closing under various conditions, including the opening height, pressure and velocity in internal flow field ,inlet pressure ,solid stress and solid strain. Finally, a test comparison shows that the effect of longitudinal seismic load on the return pressure of the relief valve can be ignored.

Research on the Influence of Throttle Valve Cage Sleeve Structure on Throttling Effect

Throttle valve is the key equipment of ultra-high pressure natural gas well, and the research on the structure and performance of the throttle valve is particularly important. Among them, the cage-type throttle valve has been studied more and more in recent years because of its many advantages. This article mainly studies the cage of the cage type throttle valve, and makes an in-depth analysis of its structure on the basis of theoretical calculations. Corresponding models are established through the wired element analysis software, and the opening positions of the valve core cage, the opening degree of the cage and the flow area change rule, the number of cage holes and the diameter of the cage are discussed. Studies have shown that when the number of small holes in the valve core cage is fixed, the flow area of the cage increases, the flow velocity in the small holes increases, and the static pressure decreases; when the flow area of the cage is fixed, the number and diameter of the throttle holes are changed, The flow rate of the flow valve is basically unchanged. It is recommended to change the diameter of the small hole and the flow area under the condition that the structure of the valve core cage is determined, and the throttling effect will be more significant.

MODELLING THE SHOCK ABSORBER PISTON VALVE USING 2-WAY FLUID-STRUCTURE INTERACTION

The aim of this study is to examine the strongly coupled Fluid-Structure Interaction approach as a comprehensive method of predicting the performance of the shock absorber piston valve. For this purpose, numerical simulation sand experimental testing are carried out. The coupled CFD-FEA numerical model described in this article, contrary to the attempts made so far, takes into account the influence of contact between valve discs and the initial conditions of the disc stack preload. The model is based on the actual valve geometry used in the shock absorber design. As a result, the described approach is intended for use in industrial applications in development works, in particular, at the conceptual stage. To prove the reliability of the model, two valve compositions are chosen to be measured on a test bench and modelled in FSI simulations. For both of them, a satisfactory level of correlation is achieved, with the correlation error below 10% and well-predicted valve opening points. As a result, it is proved that the 2- way FSI approach has great potential to be successfully used to investigate the damper valve operation.

Design and Research of 2000T Wide Plate Tensile Testing Machine

Wide plate, wide plate weld, pipeline girth weld and plate welded of panel used to the storage tank were wholly stretched by 2000T wide plate tensile test machine when using the related fixture. Tensile strength, initiation crack position of the joint crack, tolerance of the existing defects of welded joint, possibility of the crack propagation and fracture were studied. Their weak links were found, the formation of defects were avoided by welding technology and technical means. The closed loop control was realized by using advanced servo valve and high performance measure and control system, computer technology was used fully, multifunctional test control of the machine was realized. A number of servo cylinder precise synchronous control loading mechanism was adopted by 2000 T wide plate tensile testing machine, the design of its loading mode, servo cylinder, sensor installation layout and combined structure of super power sensor was the first in China, which created a platform for the development of large structure testing machine in the future.

ВСЁ НОВОЕ – ЭТО ХОРОШО ЗАБЫТОЕ СТАРОЕ: АННУЛОПЛАСТИКА МИТРАЛЬНОГО КЛАПАНА АУТОПЕРИКАРДОМ ПРИ ДЕГЕНЕРАТИВНЫХ ПОРОКАХ

Objective: To present the first-hand results of a modified mitral annuloplasty (MA) with an autopericardial strip (APS) in degenerative mitral valve disease (DMVD). Methods: Fifty-three patients with DMVD (mean age, 54.9±9.5 years (36-78 years); n=32 men (60.4%) and n=21women (39.6%)) undergoing MA with an APS, between January 2017 and January 2020 were retrospectively studied. In the overwhelming majority of cases, triangular and quadrangular resections of the P2 segment were performed. In addition, in some cases, neochords were implanted to the A2 segment. Intraoperatively, the result of MA was considered satisfactory if, according to transoesophageal echocardiography, the degree of mitral regurgitation (MR) did not exceed grade 1. Results: No in-hospital mortality was observed. One female patient had an early relapse caused by the rupture of one of the neochords at the A2 segment. However, the MR did not exceed grade 2, and the patient was actively followed up. Conclusion: Individual APS length selection avoids overcorrecting and achieves adequate systolic and diastolic mitral valve performance. Keywords: Annuloplasty, mitral regurgitation, autopericardium, mitral regurgitation.

Valve hemodynamic performance and myocardial strain after implantation of a third-generation, balloon-expandable, transcatheter aortic valve.

Left ventricular (LV) mechanics are impaired in patients with severe aortic stenosis (AS); however, transcatheter aortic valve implantation (TAVI) may positively affect LV mechanics. Assessed herein is the performance of the SAPIEN 3 transcatheter heart valve (THV) and the effect of TAVI on LV function recovery, as assessed by global longitudinal strain (GLS). A subset of patients from the SOURCE 3 registry (n = 276) from 16 European centers received SAPIEN 3 balloon-expandable THV. Echocardiography was performed at baseline, postprocedure, and at 1 year, including assessment of GLS using standard two-dimensional images, and was analyzed in a core laboratory. Paired analyses between baseline and discharge, baseline and at 1 year were conducted. Hemodynamic parameters were improved after TAVI and sustained to 1 year. At 1 year, the rate of moderate to severe paravalvular leaks (PVL), and moderate to severe mitral and tricuspid regurgitations were 1.8%, 1.7%, and 8.0%, respectively. The discharge GLS (-15.6 ± 5.1; p = 0.004; n = 149) improved significantly from baseline (-15.1 ± 4.8) following TAVI. This improvement was sustained at 1 year compared with baseline (-17.0 ± 4.6, p < 0.001; n = 100). Conversely, LV ejection fraction (LVEF) did not significantly change following TAVI (p = 0.47). Following TAVI with a third-generation THV, valve performances were good at 1 year with low PVL rate. The LV mechanics improved immediately after the procedure and were maintained at 1 year. These findings demonstrate the benefit of TAVI on LV mechanics, and suggests that GLS may be superior to LVEF in assessing this benefit. Clinicaltrial.gov number: NCT02698956.

Research on Electromagnetic Force Performance of High Speed on-off Valve

Taking a high speed on-off valve as an example, the effects of air gap, shell thickness, armature length, guide sleeve type and armature radius on the electromagnetic force performance are studied. The results show that the air gap is negatively related to the electromagnetic force, the shell thickness, armature length and armature radius are positively related to the electromagnetic force, and the effect of pure copper guide sleeve and non-guide sleeve on the electromagnetic force is basically the same. The electromagnetic force can be increased by the guide sleeve with magnetic separation ring. The influence order of parameters on electromagnetic force is: air gap &gt; armature radius increment &gt; armature length increment &gt; shell thickness increment.

Dynamic Characteristics of the Jet Force on the Flapper of the Pilot Stage in a Flapper Nozzle Servo Valve Under the Flow-Solid Interaction

Nowadays, more and more attention has been paid to improve the performance of the nozzle flapper servo valve. As a core part of nozzle flapper servo valve, the armature assembly is affected by electromagnetic force, jet force and feedback force at the same time. Due to the complex structure of the pilot stage flow field and the high jet pressure, the prediction of the jet force has always been difficult in modeling the transient motion of the servo valve. Whereupon, a numerical simulation method based on the flow-solid interaction(FSI) is applied to observe the variation of the jet force when the flapper is moving. Different parameters are employed to seek a suitable numerical simulation model which can balance the accuracy and computational cost. By comparing with the experiment results, the effectiveness of numerical simulation method in predicting the variation of the jet force and cavitation is verified. By this numerical simulation model, the distribution of flow field and the force on the flapper predicted by the moving and fixed flapper are compared. The results show that more dynamic details are achieved by the transient simulation. By analyzing the numerical simulation results of different inlet pressures and flapper vibration frequencies, the relationship between the movement of the flapper, the flow field distribution, the jet force and the inlet pressure is established, which provides a theoretical basis for the subsequent modeling of the armature assembly.

Validation of methods for effective orifice area measurement of prosthetic valves by two-dimensional and Doppler echocardiography following transcatheter self-expanding aortic valve implantation.

BackgroundThe effective orifice area (EOA) is utilized to characterize the hemodynamic performance of the transcatheter heart valve (THV). However, there is no consensus on EOA measurement of self-expanding THV. We aimed to compare two echocardiographic methods for EOA measurement following transcatheter self-expanding aortic valve implantation.MethodsEOA was calculated according to the continuity equation. Two methods were constructed. In Method 1 and Method 2, the left ventricular outflow tract diameter (LVOTd) was measured at the entry of the prosthesis (from trailing-to-leading edge) and proximal to the prosthetic valve leaflets (from trailing-to- leading edge), respectively. The velocity-time integral (VTI) of the LVOT (VTILVOT) was recorded by pulsed-wave Doppler (PW) from apical windows. The region of the PW sampling should match that of the LVOTd measurement with precise localization. The mean transvalvular pressure gradient (MG) and VTI of THV was measured by Continuous wave Doppler.ResultsA total of 113 consecutive patients were recruited. The mean age was 77.2 ± 5.5 years, and 72 patients (63.7%) were male. EOA1 with the use of Method 1 was larger than EOA2 (1.56 ± 0.39 cm2 vs. 1.48 ± 0.41 cm2, P = 0.001). MG correlated better with the indexed EOA1 (EOAI1) (r = -0.701, P < 0.001) than EOAI2 (r = -0.645, P < 0.001). According to EOAI (EOAI ≤ 0.65 cm2/m2, respectively), the proportion of sever prosthesis-patient mismatch with the use of EOA1 was lower than EOA2 (12.4% vs. 21.2%, P < 0.05). Compared with EOA2, EOA1 had lower interobserver and intra-observer variability (intra: 0.5% ± 17% vs. 3.8% ± 22%, P < 0.001; inter: 1.0% ± 9% vs. 3.5% ± 11%, P < 0.001).ConclusionsFor transcatheter self-expanding valve EOA measurement, LVOTd should be measured in the entry of the prosthesis stent (from trailing-to-leading edge), and VTILVOT should match that of the LVOTd measurement with precise localization.

Premature Structural Failure of Trifecta Bioprosthesis in Midterm Follow-up: A Single-Center Study

A cluster of aortic bioprosthetic valve failures, most of which were Trifecta bioprostheses, was observed in Southampton General Hospital, Southampton, United Kingdom. This study was performed to assess whether the cluster represents a significant failure of this valve model or whether there is a selection bias that can explain the failure of these valves. This retrospective study evaluated all bioprosthetic aortic valve replacement operations performed between 2011 and 2016 inclusive in our center. The study compared the performance of the Trifecta valve (Abbott, Abbott Park, IL) with that of Perimount (Edwards Lifesciences, Irvine, CA), Perimount Magna Ease, and Mitroflow (LivaNova, London, United Kingdom) bioprostheses. In addition, the study analyzed patient-related and valve-related risk factors for early failure in the failed valves. A total of 2807 bioprosthetic aortic valve replacements were performed. Of these, 836 were Trifecta valves, 1031 were Perimount, 449 were Perimount Magna Ease, and 351 were Mitroflow valves. A total of 24 Trifecta valves had premature structural failure, a number significantly higher than seen with Perimount or Perimount Magna Ease (no failure, P < .001 and P < .005, respectively) valves and the Mitroflow valve (1 failure, P< .05). There was no difference in the incidence of endocarditis or death. At the time of valve failure, 17 (71%) of the failed Trifecta valves had moderate or severe regurgitation, and the average peak gradient was 61 ± 29 mm Hg. The median failed prosthetic size was 23 mm. One failed valve had severe patient-prosthesis mismatch. The mean time to failure was 4.5 ± 1.7 years. The Trifecta bioprosthesis has an increased incidence of early structural valve failure, which is significantly higher than that of Perimount, Perimount Magna Ease, or Mitroflow. No patient-related or valve-related cause for the failure could be identified.

Design and numerical simulation for the development of an expandable paediatric heart valve.

Current paediatric valve replacement options cannot compensate for somatic growth, leading to an obstruction of flow as the child outgrows the prosthesis. This often necessitates an increase in revision surgeries, leading to legacy issues into adulthood. An expandable valve concept was modelled with an inverse relationship between annulus size and height, to retain the leaflet geometry without requiring additional intervention. Parametric design modelling was used to define certain valve parameter aspect ratios in relation to the base radius, Rb, including commissural radius, Rc, valve height, H and coaptation height, x. Fluid-structure simulations were subsequently carried out using the Immersed Boundary method to radially compress down the fully expanded aortic valve whilst subjecting it to diastolic and systolic loading cycles. Leaflet radial displacements were analysed to determine if valve performance is likely to be compromised following compression. Work is ongoing to optimise valvular parameter design for the paediatric patient cohort.

Simulation research on dynamic performance of the new type high-pressure solenoid valve

To improve energy density, the transportation, storage, and operations of hydrogen, methane, and compressed air vehicles currently require high-pressure compression. High-pressure solenoid valve becomes the vital element to above system. In order to reduce leakage and aerodynamic force influence, a new type high-pressure solenoid valve was proposed. The simulation model which included electromagnetic model, aerodynamic force model was established by means of the nonlinear mathematic models. Using the software MATLAB/Simulink for simulation, the dynamic response characteristics of high-pressure pneumatic solenoid valve were obtained under different pulse width modulation (PWM) input control signals. Results show that, first of all, the new type of high-pressure solenoid valve can meet the switch requirement. Secondly, the opening movement and closing movement of the spool lags the PWM rising signal, and the coil current fluctuates significantly during the movement of the spool. Lastly, on/off status of high-pressure valve cannot be represented by the duty cycle. This research can be referred in the design of the high-pressure solenoid valve..

CFD Study of Industrial Safety Valves in a Virtual Environment with OpenFOAM® Software

Numerical advances in the numerical analysis of safety valves have enabled the development of approximated predictions related to the hydraulic behavior of turbulent flows, which influence the mechanical behavior of the main components coupled to the pneumatic system. Therefore, many studies have focused on the numerical analysis of the safety valves responsible for maintaining the system integrity subject to high-pressure values under real working conditions in a virtual and inexpensive environment through the CFD codes application with OpenFOAM software. Therefore, this paper is based on the technological prediction of the laminar or turbulent flows into a safety valve through the solution of the partial differential equations system, which describes the physical state of the pressure and mass flow rate in space and time. IcoFOAM solver has been applied to model the main flow fluctuations taken, considering the mean values of the pneumatic system. A mesh independence study has been used to compute and define the finite number of nodes and cells that discretize the continuous computational domain of the internal flow and generate an approximated numerical prediction of the safety valve performance, maintaining a low computational cost during the iterative solution of the conservation equations developed with computational tools. In this sense, the RANS KEpsilon approach has defined a high prediction of the turbulent flow behavior in a virtual environment with an error rate close to the 2 percent value between the numerical and the experimental models. This research shows a good agreement in the understanding of the physical phenomena with the computational tool application based on advanced theories of thermal and fluid mechanics sciences in a virtual environment.

Valve-sparing aortic root replacement after type A aortic dissection repairs.

Aortic root reoperation after aortic dissection repair sometimes requires aortic root replacement. A valve-preserving technique should be applied when the aortic cusp is normal. Valve-sparing aortic root reconstruction using the reimplantation technique resolves aortic valve regurgitation, root dilatation, and pseudoaneurysm in the proximal anastomosis. Our experience in aortic root reoperation is presented. From January 2000 to March 2019, 26 patients underwent reoperative valve-sparing aortic root reconstruction using the reimplantation technique. The time from the initial operation to reoperation was 69.3 ± 51.6 months. Aortic root reoperation was required for a fragile wall at the previous proximal anastomosis or aortic root dilatation. We aimed to stabilize the aortic root without valve regurgitation. The native aortic cusp was aggressively preserved when nearly normal. Indications included root dilatation (n = 13), pseudoaneurysm of the previous proximal anastomosis (n = 11), and aortic valve regurgitation (n = 4). There was no early postoperative mortality. Follow-up was 49 ± 47 months (range 4-161 months). The 3, 5, and 10-year survival was 88.9% ± 7.4%, 88.9% ± 7.4%, and 77.8% ± 12.2%, respectively. Freedom from recurrence of a greater than moderate degree of aortic valve regurgitation at 3, 5, and 10 years was 86.5% ± 8.9%, 86.5% ± 8.9%, and 86.5% ± 8.9%, respectively. One patient underwent aortic valve replacement for recurrent aortic valve regurgitation 15 months after the valve-sparing reoperation. Midterm outcomes of reoperative valve-sparing aortic root reconstruction using the reimplantation technique and postoperative aortic valve performance were satisfactory.

Mathematical modeling of an armature assembly in pilot stage of a hydraulic servo valve based on distributed parameters

The dynamic performance of a nozzle-flapper servo valve can be affected by several factors such as the disturbance of the input signal, the motion of the armature assembly and the oscillation of the jet force. As the part of vibrating at high frequency, the armature assembly plays a vital role during the operation of the servo valve. In order to accurately predict the transient response of the armature assembly during the vibration, a mathematical model of armature assembly is established based on the distributed parameters method (DPM) and Hamilton principle. The new mathematical model is composed of three main parts, the modal eigenfunction, modal mechanical response expressions of the spring tube and the motion equation of the other armature assembly. After programing, the purpose of using the DPM to predict the dynamic response of different positions located on the armature assembly is achieved. For verifying the validity of the mathematical model, the finite element method (FEM) and classic model (CM) of armature assembly are applicated by commercial software under the same condition. The comparison results prove that the DPM can effectively predict the axial and tangential deflection of the armature assembly different positions which the CM can’t duing to its over-simplification. A certain error is generated when predicting the axial deformation at different heights by DPM, which is caused by an approximate method to simulate the torsion of the spring tube. The comparison results of the spring tube deflection at different vibration frequencies shows that the adaptability of DPM is significantly higher than the classic model, which verify the model is more adaptable for predicting the dynamic response of the armature assembly.

Abstract 17363: Cardiac Output and Valve Orientation Affect Blood Flow Patterns Local to Bioprosthetic Pulmonary Valves in Tetralogy of Fallot

Introduction: Tetralogy of Fallot (ToF) typically requires surgical repair of the right ventricular outflow tract (RVOT) and subsequent placement of an artificial pulmonary valve. Bioprosthetic valve longevity is highly variable and there is currently little understanding of what hemodynamic factors may lead to early valve dysfunction. Hypothesis: We hypothesize that cardiac output and valve orientation impact the performance of bioprosthetic valves by affecting blood flow patterns in the RVOT. Methods: We analyzed hemodynamics in a 3D printed ToF anatomy model in a physiological flow loop. A 25mm surgical valve was implanted in the model at two orientations: native and rotated 180 degrees. Full 3D, three-component, phase-averaged velocity fields were obtained over the cardiac cycle using 4D flow MRI at cardiac outputs of 2, 3.5, and 5 L/min. We acquired images of valve leaflet motion at 1500Hz. The 4D flow MRI and high-speed camera experiments were run identically, allowing us to examine the relationship between flow fields and leaflet motion. Results: The full velocity fields from the MRI scans revealed key differences among cases in flow features including location of reverse flow regions, systolic jet shape, and asymmetry local to the valve. At 2 L/min, the forward flow through the jet was more asymmetric compared to the other cases and a strong vortex formed, indicating a region of recirculation. With the rotated valve orientation, the 2 L/min case also produced a unique pattern as flow was washed from the RVOT inner curve back toward the center of the valve (Fig 1). Leaflet behavior during systole varied with cardiac output as well, as higher frequency flutter was observed at 5 L/min and the effective valve orifice area was decreased by 8.5% at 2 L/min compared to 5 L/min. Conclusions: We observed key differences in flow patterns and leaflet motion due to cardiac output and valve orientation that could impact leaflet loading and fatigue and long-term valve function.

Abstract 14086: Early Results of a Novel EPTFE-based Pulmonary Valved Conduit in a Pediatric Patient Population

Introduction: This prospective, multicenter, single-arm, early feasibility study evaluates the safety and performance of an investigational ePTFE-based valve for replacement of the pulmonary valve and reconstruction of the Right Ventricular Outflow Tract. A novel polymeric pulmonary valved conduit, resistant to calcification and structural valve deterioration, may provide a more durable therapy option for the pediatric population by preventing loss of right ventricular function and increased freedom from valve-related reintervention and mortality. Methods: The primary endpoints at 6 months adjudicated by an independent Clinical Events Committee are valve-related mortality and device-related reintervention. The investigational device is a valved conduit comprised of ePTFE with stretch technology and a flexible tri-leaflet polymeric valve made of an advanced proprietary composite material, which can be tailored to length requirements of the anatomy. All enrolled patients met study inclusion/exclusion criteria and had a signed informed consent form. All patients had pre- and postoperative evaluation via transthoracic echocardiography (TTE). Aspirin was administered for a minimum of three months post procedure and, per institutional protocols, four patients were on temporary Coumadin. Results: Of the 17 patients enrolled from three sites, 52.9% were male. Ages ranged from 6 to 17 years (mean 11.5 ± 3.7). BSA ranged from 0.82 to 1.57 m 2 . At six months follow up, 100% of subjects successfully met the primary endpoint of freedom from valve-related mortality and device-related reintervention. No patient exhibited an RVOT gradient &gt; 20 mmHg. No patients had pulmonary regurgitation above baseline (≤ mild) observed through six months. Throughout postoperative serial TTE evaluation at discharge, 1, 3, and 6 months, no evidence of worsening valvular insufficiency was observed. No patient developed endocarditis and TTE detected no clinically significant thrombus formation. Conclusions: These preliminary data of a novel Pulmonary Valve Conduit suggest improved pulmonic and right ventricular function based on TTE measurements, no unexpected findings, no valve-related adverse events and encouraging hemodynamic performance through 6 months.