Bovine Jugular Vein Conduit Research Articles

Right ventricle to pulmonary artery conduit: a comparison of long-term graft-related events between bovine jugular vein conduit, aortic homograft, and porcine-valved conduits.

The optimal conduit for right ventricle to pulmonary artery (RV-PA) reconstruction does not exist. Reinterventions are common due to conduit stenosis and endocarditis. Tailoring conduit choice according to patients' characteristics could improve the outcomes. The study aimed to compare graft-related events (infective endocarditis, transcatheter pulmonary valve replacement (PVR), transcatheter conduit dilatation, surgical conduit replacement, and transcatheter pulmonary branch intervention for RV-PA reconstruction using bovine jugular vein, aortic homograft, and porcine-valved conduits. In a retrospective cohort study, 155 patients with 193 procedures that were done in King Faisal Specialist Hospital and Research Center-Jeddah (KFSHRC JED) for implanting RV-PA conduits from 1999 to 2021 were included. The patients were grouped according to the type of conduit into 3 groups; Group 1 (n=153) received bovine jugular vein (BJVs) grafts, Group 2 (n=29) received aortic homografts, Group 3 (n=11) received porcine-valved conduits. Factors associated with graft-related events were evaluated using stepwise Cox regression analysis. Patients with BJVs were significantly younger than those with porcine-valved conduits 3 (P=0.009). The weight of BJVs patients was significantly lower than homografts (P=0.002) and porcine-valved conduits patients 3 (P<0.001). The conduit size was as expected significantly lower in BJVs patients than patients who received porcine-valved conduits (P<0.001) and patients who received aortic homografts (P<0.001). There was no difference between Group 2 and 3 (P=0.084). Operative mortality occurred in 13 patients: 12 (7.84%) with BJV conduit and 1 (9.09%) with porcine valved conduit (P=0.351). Male gender [odds ratio (OR): 10.04; 95% confidence interval (CI): 1.28-78.86; P=0.028] and smaller conduit size (OR: 0.78; 95% CI: 0.61-0.99; P=0.048) were associated with increased operative mortality. Freedom from graft-related events at 5 and 10 years was 67% and 52% in BJVs patients, 74% and 36% in patients who received aortic homografts, and 53% in patients who received porcine-valved conduits. Factors associated with increased graft-related events were male gender (HR: 1.58; 95% CI: 1.004-2.50, P=0.048) and younger age (HR: 0.995; 95% CI: 0.991-0.999, P=0.041). RV-PA reconstruction was associated with low mortality, unrelated to the conduit type. Reinterventions for graft-related events were common. The durability and graft-related events might be comparable among BJV grafts, aortic homografts, and porcine-valved conduits. Factors associated with increased graft-related events in this study were male gender and younger age.

Epoxy- versus Glutaraldehyde-Treated Bovine Jugular Vein Conduit for Pulmonary Valve Replacement: A Comparison of Morphological Changes in a Pig Model.

Valved conduits are often required to replace pulmonary arteries (PA). A widely used Contegra device is made of bovine jugular vein (BJV), preserved with glutaraldehyde (GA) and iso-propanol. However, it has several drawbacks that may be attributed to its chemical treatment. We hypothesized that the use of an alternative preservation compound may significantly improve BJV conduit performance. This study aimed to compare the macroscopic and microscopic properties of the BJV treated with diepoxide (DE) and GA in a porcine model. Twelve DE-BJVs and four Contegra conduits were used for PA replacement in minipigs. To assess the isolated influence of GA, we included an additional control group-BJV treated with 0.625% GA (n = 4). The animals were withdrawn after 6 months of follow-up and the conduits were examined. Explanted DE-BJV had a soft elastic wall with no signs of thrombosis or calcification and good conduit integration, including myofibroblast germination, an ingrowth of soft connective tissue formations and remarkable neoangiogenesis. The inner surface of DE-BJVs was covered by a thin neointimal layer with a solid endothelium. Contegra grafts had a stiffer wall with thrombosis on the leaflets. Calcified foci, chondroid metaplasia, and hyalinosis were observed within the wall. The distal anastomotic sites had hyperplastic neointima, partially covered with the endothelium. The wall of GA-BJV was stiff and rigid with degenerative changes, a substantial amount of calcium deposits and dense fibrotic formations in adventitia. An irregular neointimal layer was presented in the anastomotic sites without endothelial cover in the GA BJV wall. These results demonstrate that DE treatment improves conduit integration and the endothelialization of the inner surface while preventing the mineralization of the BJV, which may reduce the risk of early conduit dysfunction.

20-Year follow-up and comparison of valved conduits used for right ventricular outflow tract reconstruction: single-centre, propensity score match analysis.

Surgical repair of complex congenital heart defects with hypoplasia or atresia of the right ventricular outflow tract (RVOT) may require pulmonary valve implantation or replacement during the primary repair or reoperation. The purpose of this study is to evaluate the outcomes of cryopreserved homografts, bovine jugular vein conduits and decellularized Matrix P Plus N conduits in patients undergoing RVOT reconstruction at a single centre. Retrospective, single-centre review of 173 patients with 199 conduits undergoing right ventricle-to-pulmonary artery reconstruction with valved conduit from 2002 to 2022. A total of 199 conduits were implanted in 173 patients (62.8% male), with a mean age of 8.97 ± 8.5 years. The following 3 types of conduits were used: homografts 129 (64.8%), bovine jugular vein conduits 45 (22.7%) and Matrix P Plus N 25 (12.5%). During the mean follow-up duration of 8.6 ± 5.8 years, there were 20 deaths, 35 conduit reoperations and 44 catheter reinterventions. Overall survival, reoperation-free and catheter reintervention-free survival at 20 years were 83%, 67.8% and 65.6%, respectively. Multivariable Cox analysis identified younger patient age, smaller conduit size, low patient weight and primary diagnosis of common arterial trunk as risk factors for reoperation and catheter reintervention. Long-term outcomes of reconstruction of the RVOT using homografts, bovine jugular vein and Matrix P Plus N conduits were acceptable. The reoperation rate for conduit dysfunction did not differ significantly among groups. Over time, the need for conduit replacement was higher in smaller conduits and in patients with common arterial trunk diagnosis.

Pentagalloyl glucose-stabilized decellularized bovine jugular vein valved conduits as pulmonary conduit replacement

Congenital heart diseases (CHD) are one of the most frequently diagnosed congenital disorders, affecting approximately 40,000 live births annually in the United States. Out of the new patients diagnosed with CHD yearly, an estimated 2,500 patients require a substitute, non-native conduit artery to replace structures congenitally absent or hypoplastic. Devices used for conduit replacement encounter limitations exhibiting varying degrees of stiffness, calcification, susceptibility to infection, thrombosis, and a lack of implant growth capacity. Here, we report the functionality of pentagalloyl glucose (PGG) stabilized decellularized valved bovine jugular vein conduit (PGG-DBJVC). The PGG-DBJVC tissues demonstrated mechanical properties comparable to native and glutaraldehyde fixed tissues, while exhibiting resistance to both collagenase and elastase enzymatic degradation. Subcutaneous implantation of tissues established their biocompatibility and resistance to calcification, while implantation in sheep in the pulmonary position demonstrated adequate implant functionality, and repopulation of host cells, without excessive inflammation.In conclusion, this PGG-DBJVC device could be a favorable replacement option for pediatric patients, reducing the need for reoperations required with current devices. Statement of significanceCongenital Heart Disease (CHD) is a common congenital disorder affecting many newborns in the United States each year. The use of substitute conduit arteries is necessary for some patients with CHD who have missing or underdeveloped structures. Current conduit replacement devices have limitations, including stiffness, susceptibility to infection and thrombosis, and lack of implant growth capacity. Pentagalloyl glucose-stabilized bovine jugular vein valved tissue (PGG-DBJVC) offers a promising solution as it is resistant to calcification, and biocompatible. When implanted in rats and as pulmonary conduit replacement in sheep, the PGG-DBJVC demonstrated cellular infiltration without excessive inflammation, which could lead to remodeling and integration with host tissue and eliminate the need for replacement as the child grows.

Long-Term Outcomes After Right Ventricular Outflow Tract Conduit Placement

Objective: Our aim was to report on the long-term outcomes of patients who underwent RV-PA conduit placement at our institute. Materials and Methods: We retrospectively reviewed 407 RV-PA conduit placements from January 1997 to December 2018. The primary outcomes were freedom from and risk factor(s) for conduit re-operation. The secondary outcomes were survival, freedom from conduit dysfunction and conduit-related catheter intervention. Results: Of all the included patients, 209 were male (51.4%) and the median age at the operation was nine years (IQR 6, 18 years). The most commonly used conduit types were bovine jugular vein conduit (125, 30.7%), pulmonary homograft (122, 30.0%), and aortic homograft (76, 18.7%). The median follow-up time was 5.1 years (IQR 0.9, 9.2 years). The overall survival was 92.2% at 5 years. Freedom from re-operation was 95.4% and 84.2%, at 5 and 10 years. Factors related to conduit reoperation were age at operation less than 1 year, diagnosis rather than pulmonary atresia or stenosis, conduit size less than 18 mm, and conduit z-score greater than 3 (all p&lt;0.01). In multivariate analysis, a significant contributing factor for re-operation was small conduit size (13 mm or smaller; HR 6.87 (95%CI 2.36, 20.01); p&lt;0.001, 14–17 mm; HR 3.20 (95%CI 1.28, 8.00); p=0.013). Freedom from conduit dysfunction was 84.4% and 61.6% at 5 and 10 years. Freedom from conduit intervention was 94.4% and 89.3% at 5 and 10 years. Conclusion: Our study showed that patients had excellent survival with acceptable freedom from re-operation despite deteriorated conduit function. Small conduit size is associated with re-operation.

Bovine jugular vein conduit replacement after homograft degeneration in patients with tetralogy of Fallot: The results of re-redo cases.

This study aims to present our experience and results in terms of reconstruction with bovine jugular vein conduit in re-redo patients who developed severe homograft degeneration with pulmonary homograft valve replacement. Between May 2018 and May 2021, a total of 10 re-redo patients (4 males, 6 females; mean age: 16.5±3.0 years; range, 12 to 21 years) who underwent bovine jugular vein conduit replacement due to homograft degeneration were retrospectively analyzed. The clinical, pre-, intra-, and postoperative data of the patients were recorded. The mean age of the second operation (homograft replacement) was 8.5±3.8 (range, 4 to 14) years in the patients who underwent homograft replacement. No postoperative mortality was observed. When the pre- and postoperative findings were compared, the right ventricular outflow tract gradient, the degree of pulmonary and tricuspid regurgitation, and right ventricular dilatation were regressed (p<0.05). A significant improvement in the New York Heart Association functional class was observed in all patients after surgery. After tetralogy of Fallot corrective surgery, repetitive surgical interventions are inevitable due to pulmonary valve deterioration. Therefore, a bovine jugular vein conduit may be a good alternative for conduit preference after pulmonary homograft failure in re-redo cases.

Matched comparison of decellularized homografts and bovine jugular vein conduits for pulmonary valve replacement in congenital heart disease

For decades, bovine jugular vein conduits (BJV) and classic cryopreserved homografts have been the two most widely used options for pulmonary valve replacement (PVR) in congenital heart disease. More recently, decellularized pulmonary homografts (DPH) have provided an alternative avenue for PVR. Matched comparison of patients who received DPH for PVR with patients who received bovine jugular vein conduits (BJV) considering patient age group, type of heart defect, and previous procedures. 319 DPH patients were matched to 319 BJV patients; the mean age of BJV patients was 15.3 (SD 9.5) years versus 19.1 (12.4) years in DPH patients (p = 0.001). The mean conduit diameter was 24.5 (3.5) mm for DPH and 20.3 (2.5) mm for BJV (p < 0.001). There was no difference in survival rates between the two groups after 10 years (97.0 vs. 98.1%, p = 0.45). The rate of freedom from endocarditis was significantly lower for BJV patients (87.1 vs. 96.5%, p = 0.006). Freedom from explantation was significantly lower for BJV at 10 years (81.7 vs. 95.5%, p = 0.001) as well as freedom from any significant degeneration at 10 years (39.6 vs. 65.4%, p < 0.001). 140 Patients, matched for age, heart defect type, prior procedures, and conduit sizes of 20–22 mm (± 2 mm), were compared separately; mean age BJV 8.7 (4.9) and DPH 9.5 (7.3) years (p = n.s.). DPH showed 20% higher freedom from explantation and degeneration in this subgroup (p = 0.232). Decellularized pulmonary homografts exhibit superior 10-year results to bovine jugular vein conduits in PVR.

20-year follow-up and comparison of homografts with bovine jugular vein conduits in children less than 2 years of age.

Repair of congenital heart defects involving right ventricular outflow tract (RVOT) may require pulmonary valve replacement at time of primary repair or reoperation. This study compares the outcomes of cryopreserved homografts with bovine jugular vein conduits (BJVC) in children < 2 years of age with RVOT reconstruction. Retrospective, single-center review of 70 conduits implanted in 63 patients undergoing right ventricle-to-pulmonary artery reconstruction with valved conduit from 2002 to 2022. A total of 70 conduits were implanted in 63 patients, with mean age of 4.5 ± 6.9 months (range 1 day ‒ 23.5 months).The following conduits were used; homografts 38 (54.2 %), BJVC 32 (45.8 %). During mean follow-up of 6.2 ± 5.6 years, there were 12 deaths, 24 conduit reoperations, and 25 catheter reinterventions. Overall survival, reoperation-free, and catheter reintervention-free survival at 15 years was 82.7 %, 31.2 %, and 25.7 %, respectively. Multivariate analysis revealed that low patient weight, age < 30 days at repair, ventilation time, and ICU length of stay were associated with increased risk of death. The performance of homografts and BJVC is comparable in patients ent between the two groups (Tab. 3, Fig. 3, Ref. 16).

Infant Mitral Valve Replacement: Current State of the Art.

Mitral valve replacement (MVR) in the very young is an imposing clinical challenge. Early and late mortality risk is substantial, severe adverse events are common, and redo mitral valve replacement is inevitable. Therapeutic options are limited. In the older infant with an annulus of 17mm or larger, mechanical MVR is associated with low risk of mortality and predictable durability. For the very young with annular hypoplasia, bovine jugular vein conduit MVR appears to offer equivalent or better early outcomes with the possibility of subsequent valve expansion, potentially prolonging the interval to redo MVR. Experience with cylinder MVR and other forms of surgeon-manufactured MVR is quite limited, and there is currently no information on late outcomes or durability.

Diepoxy-treated bovine jugular vein conduit for pulmonary artery replacement

Objective: To evaluate the performance and short-term capacity of the diepoxy-treated bovine jugular vein conduit in large animals during 6-month follow-up.Methods: Thirteen diepoxy-treated bovine jugular vein conduits were implanted into the pulmonary artery of young mini-pigs. During the follow-up, graft function was tested using transesophageal echocardiography. The animals were withdrawn at 6 months, and the explanted conduits were assessed histologically.Results: All the conduits were successfully implanted without any surgical complications. All the animals survived throughout the follow-up. By the end of the follow-up period, the pressure gradient increased on five animals’ conduits including one case of mismatch between the conduit and the native pulmonary artery, two cases of distal stenosis, and two case of endocarditis. No significant increase in valve regurgitation or conduit thrombosis was observed during the follow-up. In conduits without dysfunction, the structure of the walls and leaflets was intact. A thin fibrous tissue covered the conduit inner wall with complete surface endothelialization. Neither signs of degeneration or calcification nor inflammatory cells were found in the conduit wall or leaflets. Neointima proliferation without calcium deposits was observed in two distally stenosed conduits. Inflammatory cells consisting of multinucleated macrophages, lymphocytes, and histiocytes were found in the adventitia. There were no inflammatory cells in the media or intima, and the leaflets showed no changes.Conclusion: Diepoxy-treated bovine jugular vein demonstrated acceptable performance, good endothelialization, and low tendency to thrombosis and calcium accumulation in the wall and leaflets. Received 31 October 2022. Revised 25 November 2022. Accepted 28 November 2022. Funding: The study was supported by Russian Science Foundation (grant No. 22-25-20102). Conflict of interest: The authors declare no conflict of interest. Contribution of the authorsConception and study design: N.R. Nichay, I.Yu. Zhuravleva, A.V. Bogachev-ProkophievData collection and analysis: N.R. Nichay, Yu.Yu. Kulyabin, I.S. Zykov, E.V. Boyarkin, O.Yu. Malakhova, E.V. Kuznetsova, T.P. Timchenko, Ya.L. Rusakova, I.S. Murashov, A.A. DokuchaevaStatistical analysis: N.R. Nichay, I.Yu. ZhuravlevaDrafting the article: N.R. Nichay, I.Yu. Zhuravleva, Yu.Yu. Kulyabin, I.S. Zykov, E.V. Boyarkin, O.Yu. Malakhova, T.P. Timchenko, Ya.L. Rusakova, I.S. Murashov, A.A. DokuchaevaCritical revision of the article: N.R. Nichay, I.Yu. Zhuravleva, Yu.Yu. Kulyabin, A.A. Dokuchaeva, A.V. Bogachev-ProkophievFinal approval of the version to be published: N.R. Nichay, I.Yu. Zhuravleva, Yu.Yu. Kulyabin, I.S. Zykov, E.V. Boyarkin, O.Yu. Malakhova, E.V. Kuznetsova, T.P. Timchenko, Ya.L. Rusakova, I.S. Murashov, A.A. Dokuchaeva, A.V. Bogachev-Prokophiev

Decellularized bovine jugular vein and hand-sewn ePTFE valved conduit for right ventricular outflow tract reconstruction in children undergoing Ross procedure.

BackgroundThe Ross procedure is recommended as an optimal aortic valve replacement (AVR) in children and young adults due to several advantages. Nevertheless, multiple reconstructions of the right ventricular outflow tract (RVOT) with new valve conduits have caused some concern regarding the durability of the Ross AVR. Decellularized bovine jugular vein conduit (BJVC) (DP-BJVC) and hand-sewn expanded polytetrafluoroethylene valved conduits (ePTFE VC) are widely employed to reconstruct the RVOT with satisfactory long-term outcomes. However, few studies have compared the safety and efficacy between the two valve conduits. We aimed to evaluate the early outcomes and report our single center experience in the application of these conduits.MethodsTwenty-two pediatric patients (aged < 18 years) who underwent Ross procedures with DP-BJVC and ePTFE VC in our center between 1 June, 2017 and 31 January, 2022 were enrolled. The Kaplan–Meier method was used to evaluate survival, freedom from RVOT reintervention, and freedom from RVOT graft dysfunction. Mixed-effects analysis with the Geisser–Greenhouse correction and Sidak's multiple comparisons test for post-hoc analysis was employed to compare the peak gradient across the conduit at varying follow-ups.ResultsAll patients were followed up in full. The total early survival rate was 90.9%; two patients in the DP-BJVC group died. There was no significant difference in early mortality, cross-clamp time (p = 0.212), in-hospital stay (p = 0.469), and RVOT graft thrombosis or endocarditis between the two groups. There was similarly no significant difference between Kaplan–Meier freedom from RVOT graft dysfunction curve (P = 0.131). The transprosthetic gradient gradually increased over time in both groups and was significantly higher in the DP-BJVC group at follow-up (P < 0.05).ConclusionsBoth conduits show excellent early and midterm outcomes for RVOT reconstruction in the Ross procedure. We suggest that DP-BJVC is more suitable for infants, and ePTFE conduit is more suitable for older children who require larger conduits.

Current development of bovine jugular vein conduit for right ventricular outflow tract reconstruction.

Right ventricular outflow tract (RVOT) reconstruction is a common surgical method to treat congenital cardiac lesions, and bovine jugular vein conduit (BJVC) has become a prevalent candidate of prosthetic material for this procedure since 1999. Although many clinical studies have shown encouraging results on BJVCs, complications such as stenosis, aneurysmal dilatation, valve insufficiency, and infective endocarditis revealed in other clinical outcomes still remain problematic. This review describes the underlying mechanisms causing respective complications, and summarizes the current technological development that may address those causative factors. Novel crosslinking agents, decellularization techniques, conduit coatings, and physical reinforcement materials have improved the performances of BJVCs. The authors expect that the breakthroughs in the clinical application of BJVC may come from new genetic research findings and advanced characterization apparatuses and bioreactors, and are optimistic that the BJVC will in the future provide sophisticated therapies for next-generation RVOT reconstruction.

Risk factors for early adverse outcomes after bovine jugular vein conduit implantation: influence of oversized conduit on the outcomes

OBJECTIVESWe investigated potential risk factors for early failure of bovine jugular vein conduit (Contegra®) implantation for right ventricular outflow tract (RVOT) reconstruction.METHODSA single-centre retrospective review of 115 consecutive patients (54 males) who underwent RVOT reconstruction with Contegra between 2016 and 2019 was performed. Overall survival, explantation-free survival and freedom from significant RVOT lesions (valve regurgitation ≥ moderate or flow velocity ≥3.5 m/s) were investigated.RESULTSMedian age, body weight and Contegra diameter were 10.3 months [interquartile range (IQR) 5.7–26.9 months], 7.8 kg (IQR 6.3–12.4 kg) and 14 mm (IQR 12–16 mm), respectively. During the median follow-up duration of 25.1 months, there were 7 deaths, 34 significant RVOT lesions, 10 endocarditis episodes and 15 explantations. Overall survival and explantation-free survival at 3 years were 94.8% and 78.4%, respectively. Significant RVOT lesions (n = 34) comprised 20 stenoses, 8 regurgitations and 6 combined lesions. Freedom from significant RVOT lesions at 3 years was 62.6%. Cox regression identified higher indexed Contegra size (Contegra diameter/body weight, mm/kg) as the only risk factor for decreased time to explantation or death (hazard ratio 2.32, P < 0.001) and time to significant RVOT lesions development (hazard ratio 2.75, P < 0.001). The cut-off value of indexed Contegra size for significant RVOT lesions at 12 months was 1.905 mm/kg (sensitivity, 0.75; specificity, 0.78; area under the curve, 0.82).CONCLUSIONSOutcomes of RVOT reconstruction using Contegra were acceptable. However, oversized Contegra should be avoided when possible.IRB APPROVAL DATE26 October 2020.IRB REGISTRATION NUMBERS2020-2505-0001

Ross Procedure in the era of Handmade-Valved Conduits for Right Ventricular Outflow Tract Reconstruction in Children: Short-Term Surgical Outcomes.

ObjectiveRoss procedure is considered as the “gold standard” for aortic valve replacement, but the conduits used for right ventricular outflow tract (RVOT) reconstruction, such as homografts and bovine jugular vein (BJV) conduits, are of limited availability in China. Handmade expanded polytetrafluoroethylene-valved conduits (HVCs) have been used recently as the alternative for RVOT reconstruction, but their specific experience in Ross procedure is limited in the literature.MethodsThis was a retrospective review of 27 children who underwent Ross procedure in our center from January 2018 to January 2022.ResultsMean age at surgery was 8.0 ± 3.8 years. During the study period, BJV conduits were used for RVOT reconstruction in 6 patients (22%), and HVCs were used in 21 patients (78%). Median conduit size was 20 mm (range, 16–24 mm), and mean conduit Z-score was +0.8 ± 0.9. Median time for cardiopulmonary bypass was 158 min (range, 109–275 min), and mean time for aortic crossclamping was 110 ± 21 min. There was no early mortality. During a median follow-up time of 1.4 years (range, 0.1–3.7 years), 3 patients (11%) with BJV conduits had peak conduit velocity of > 3.5 m/s; 3 patients (11%) with HVCs developed moderate conduit insufficiency; no patients had more than moderate conduit insufficiency. Three patients with BJV conduits had 5 reinterventions, and all received conduit replacement with HVCs.ConclusionHVC is an appealing alternative to BJV conduit for RVOT construction for children undergoing Ross procedure, with favorable short-term outcomes.

Individualized right ventricular outflow tract reconstruction using autologous pulmonary tissue in situ for the treatment of pulmonary atresia with ventricular septum defect.

The study aims to evaluate the feasibility and effectiveness of an individualized procedure for right ventricular outflow tract (RVOT) reconstruction in pulmonary atresia with ventricular septal defect (PA-VSD). RVOT was reconstructed using autologous pulmonary artery tissue preserved in situ as the posterior wall and a bovine jugular vein patch (BJVP) as the anterior wall in patients with PA-VSD (observation group). The size of the BJVP made from a bovine jugular vein conduit (BJVC) was individually calculated using a formula based on the child's weight and the size of the autologous pulmonary artery (the diameter of BJVC DB⁢J⁢V⁢C = Dt⁢h⁢e⁢o⁢r⁢e⁢t⁢i⁢c⁢a⁢l-W⁢z^-4π). Its effect was then compared with the conventional modified Rastelli procedure based on the BJVC (control group). A total of 22 patients that underwent the new procedure were simultaneously compared with the 25 patients in the control group. No deaths occurred in both groups. Notably, there were no significant differences in mechanical ventilation, ICU and postoperative residence, cardiopulmonary bypass, and aortic cross-clamp time. In the follow-up, which spanned for 8-12 years (mean 9.2 years), only four cases with moderate regurgitation were noted in the observation group without obstruction. In the control group, two patients had a conduit replacement. Three patients suffered from anastomotic stenosis, which was corrected by balloon dilatation. Individualized RVOT reconstruction with autologous pulmonary tissue preserved in situ as the posterior wall is adequate for treating PA-VSD.

Hand-sewn expanded polytetrafluoroethylene valved conduit for right ventricular outflow tract reconstruction.

Due to the lack of large-sized pulmonary valved conduit products in clinical practice, hand-sewn expanded polytetrafluoroethylene (ePTFE) valved conduit has been used for right ventricular outflow tract (RVOT) reconstruction in many heart centers around the world. This study aims to summarize the early results of the ePTFE valved conduit and the sewing technology of the conduit in combination with the latest progress, and to provide a reference for the application of ePTFE valved conduit. A total of 21 patients using ePTFE valved conduit for RVOT reconstruction in the Second Xiangya Hospital, Central South University from October 2018 to October 2020 were prospectively enrolled in this study. The age at the implantation of the conduit was 4.3 to 43.8 (median 15.1) years old, with weight of (38.9±4.1) kg. In this cohort, 14 patients underwent re-reconstruction of RVOT, including 12 patients with pulmonary regurgitation at 6.3 to 31.0 (median 13.8) years after tetralogy of Fallot (TOF) repair, and 2 patients with failed bovine jugular vein conduit (BJVC). Seven patients underwent Ross operations. Among them, 3 were for aortic valve stenosis, 2 were for aortic regurgitation, and 2 were for both stenosis and regurgitation. The ePTFE valved conduits were standard hand-sewn during the surgery. The 3 leaflets were equal in size with arc-shaped lower edge of the valve sinus. The free edge of the valve leaflets was straight with the length of about 1 mm longer than the diameter. The height of the valve sinus was 4/5 of the diameter. The junction of the valve leaflet was 3/4 of the height of the sinus. The designed leaflets were then continuous non-penetrating sutured into the inner surface of Gore-Tex vessel to make a valved conduit. Valved conduits with diameter of 18, 20, and 22 mm were used in 2, 9, and 10 cases, respectively. The surgical results, postoperative recovery time, and serious complications were summarized, and the changes of postoperative cardiac function status and hemodynamic status of the conduits were investigated. During the implantation of ePTFE valved conduit for RVOT reconstruction, 2 patients underwent mechanical mitral valve replacement with Ross operation, 2 patients with pulmonary regurgitation with repaired TOF underwent left and right pulmonary artery angioplasty, and 1 patient with failed BJVC underwent tricuspid valvuloplasty. The cardiopulmonary bypassing time for patients underwent re-reconstruction of RVOT was (130.9±16.9) min, with aorta clamping for 1 patient to repair the residual defect of the ventricular septum. The cardiopulmonary bypassing and aorta clamping time for Ross operation were (242.7±20.6) min and (145.6±10.5) min, respectively. The duration of postoperative ventilator assistance, intensive care unit stay, and hospital stay were 3.5 h to 7.7 d (median 17.1 h),11.2 h to 29.5 d (median 1.9 d), and 6.0 to 56.0 (median 13.0) d, respectively. All patients survived after discharge from hospital. The follow-up rate after discharge was 100% with median time at 15.0 (13.0 to 39.0) months. No death happened during the follow-up. One patient underwent stent implantation due to right coronary stenosis 2 months after Ross operation. One patient underwent balloon dilation due to right pulmonary artery ostium stenosis 1 year after re-reconstruction of RVOT. The cardiac function of all patients recovered to NYHA class I 6 months after operation. The peak pressure gradient across the valve measured by transthoracic echocardiography before discharge was (9.4±2.6) mmHg (1 mmHg=0.133 kPa), and (18.3±6.1) mmHg at the last follow-up. There was no significant increase in the gradient during the follow-up (P=0.134). No patient suffered from mild or more pulmonary regurgitation. Hand-sewn ePTFE valved conduit is feasible for RVOT reconstruction. It is a promising material for RVOT reconstruction which can effectively meet clinical need. In our experience, the ePTFE valved conduit is simple to manufacture with satisfactory early outcomes.In the application of ePTFE valved conduit, attention should be paid to implantation indications and postoperative anticoagulation management, especially to the preparation details of the valved conduit, to obtain better function and durability of the conduit after implantation.

Comparison of homografts and bovine jugular vein conduits in the pulmonary position in patients

ObjectiveTo compare the performance of homografts and bovine jugular vein (BJV) conduits in the pulmonary position. MethodsAll patients with congenital heart disease up to age 20 years who underwent pulmonary valve replacement with homografts or BJV at 3 centers in Australia were evaluated. There were 674 conduits, with 305 (45%) pulmonary homografts (PHs), 303 (45%) BJV conduits, and 66 (10%) aortic homografts (AHs). Endpoints were freedom from reintervention, structural valve degeneration (SVD), and infective endocarditis (IE). Propensity score matching was used to balance the comparison of PH and BJV conduits. ResultsThe median follow-up was 6.4 years (interquartile range, IQR, 3.1-10.7 years). Freedom from reintervention at 5 and 10 years was 92% and 80%, respectively, for PH, 74% and 37% for BJV, and 75% and 47% for AH. BJV conduits had a higher risk of reintervention (P < .001) and SVD (P < .001) compared with PHs. These findings were confirmed with propensity score matching valid for conduit size >15 mm. AHs >15 mm had a higher risk of reintervention (P < .001) and SVD (P < .001) compared with PHs >15 mm. The performance of AHs and BJV conduits was similar across all sizes (reintervention, P = .94; SVD, P = .72). The incidence of IE was 1% for PH, 10% for BJV, and 1.5% for AH. ConclusionsIn patients age <20 years with a conduit >15 mm, PHs outperformed BJV conduits and AHs in the pulmonary position. The performance of AH and BJV was comparable. Small conduits (≤15 mm) had similar performance across all conduit types.

Conduits for Right Ventricular Outflow Tract Reconstruction in Infants and Young Children.

Purpose of Review: Right ventricular outflow tract (RVOT) reconstruction remains a challenge due to the lack of an ideal conduit. Data and experience are accumulating with each passing day. Therefore, it is necessary to review this topic from time to time. This is a 2021 update review focused on the history, evolution, and current situation of small-sized conduits (≤ 16 mm) for RVOT reconstruction in infants and young children.Recent Findings: Currently, the available small-sized (≤16 mm) conduits can meet most clinical needs. Homograft is still a reliable choice for infants and young children validated by a half-century clinical experience. As an alternative material, bovine jugular vein conduit (BJVC) has at least comparable durability with that of homograft. The performance of expanded polytetrafluoroethylene (ePTFE) is amazing in RVOT position according to limited published data. The past century has witnessed much progress in the materials for RVOT reconstruction. However, lack of growth potential is the dilemma for small-sized conduits. Tissue-engineering based on cell-free scaffolds is the most promising technology to obtain the ideal conduit.Summary: No conduit has proved to have lifelong durability in RVOT position. We are far from the ideal, but we are not in a state of emergency. In-depth clinical research as well as innovation in material science are needed to help improve the durability of the conduits used in infants and young children.

Midterm Outcomes of Crosslinked Acellular Bovine Jugular Vein Conduit for Right Ventricular Outflow Tract Reconstruction.

Objectives: Conduits for reconstructing right ventricular outflow tract (RVOT) in children with congenital heart disease have evolved for better durability over the past decades, but conduits failure remains common. We designed decellularized and photooxidatively crosslinked bovine jugular vein conduit (DP-BJVC) and now aim to evaluate the midterm results of DP-BJVC for RVOT reconstruction.Methods: Ninety patients (median age: 4.2 years) undergoing RVOT reconstruction using DP-BJVC were prospectively followed for median of 4.7 years (range: 0.2–16.1 years). Kaplan–Meier analysis was used to examine the survival, freedom from conduit explantation and catheter-based reintervention. Risk factors were analyzed with Cox regression analysis.Results: Follow-up was completed in 92% of patients. There were five (5.6%) early deaths. The 10-year survival rate was 85.2%, with palliative procedure at DP-BJVC implantation as the risk factor. The 10-year freedom from conduit explantation and reintervention were 84.4 and 67.3% respectively, with previous cardiac operation as the only risk factor for explantation. Complications during the follow-up included conduit stenosis (peak gradient ≥50 mmHg) in 12 (12.9%), severe regurgitation in 2 (2.4%), and infective endocarditis in 2 (2.4%). The annual increase in gradient was highest in the first year (P = 0.003), but not appreciably afterwards. The echo-measured annulus diameter trends to increase by an average of 0.37 mm per year. Calcification appeared mild in the failed conduits.Conclusions: DP-BJVC provides satisfactory durability and functionality for RVOT reconstruction for children, with low morbidity of stenosis and endocarditis, as well as increase in diameter mildly with age in midterm follow-ups.

Bovine jugular vein conduit: What affects its elastomechanical properties and thermostability?

The aim of this study was to compare the mechanical properties and thermal stability of the venous wall depending on the treatment method used, and, accordingly, on those structural changes in the tissue that this treatment causes. Bovine jugular vein walls (BJVWs) cross-linked with glutaraldehyde (GA), ethylene glycol diglycidyl ether (DE), and Contegra commercial conduit were evaluated using uniaxial stretching [with and without pre-conditioning (PreC)], differential scanning calorimetry, amino acid analysis, and attenuated total reflection infrared spectroscopy. Fresh BJVW was used as a control. It was shown that failure stress in non-PreC GA-treated and DE-treated materials was lower than that in fresh and Contegra counterparts. Contegra samples were the stiffest among the tested materials. Cyclic preloading leads to distortion of the mechanical behavior of this material, which is heterogeneous in composition and structure. The denaturation temperatures (Td ) of all cross-linked BJVWs were higher than the Td of the fresh vein. The microstructures of the tested BJVWs did not exhibit any differences, but the cross-linking density and hydration of the DE-vein were the highest. GA-cross-linking or DE-cross-linking and isopropanol exposure (Contegra) changed the protein secondary structures of the tested materials in different ways. We hypothesized that the protein secondary structure and hydration degree are the main causes of differences in the mechanical properties and thermal stability of BJVW.