Right Ventricular Outflow Tract Reconstruction Research Articles

Quantitative Evaluation of Right Ventricular Workload Based on the Stroke Work Index in Patients after Right Ventricular Outflow Tract Reconstruction.

The evaluation of right ventricular workload is sometimes complicated in patients after right ventricular outflow tract reconstruction (RVOTR) because both stenotic and regurgitation lesions are involved. In this study, we modified the right ventricular stroke work index (RVSWI) and evaluated the relationship between the modified RVSWI (mRVSWI) and patient prognosis after RVOTR.We enrolled 69 patients who underwent RVOTR (the RVOTR group), including those who needed early reoperation (early reoperation subgroup) and those who did not (follow-up subgroup), and 13 age-matched control participants (control group). Based on the catheterization results 1year after RVOTR, we compared the mRVSWI between these groups. Additionally, we evaluated the influence of the mRVSWI on the reoperation avoidance rate and survival.The mRVSWI in the RVOTR group was significantly greater than that in the control group (17.7 ± 8.6 vs. 11.0 ± 2.7g·m/m2, p = 0.008). The mRVSWI in the early reoperation subgroup was significantly greater than that in the follow-up subgroup (32.5 ± 11.1 vs. 15.8 ± 6.0g·m/m2, p < 0.0001). In the follow-up subgroup, patients with an mRVSWI higher than the upper limit of normal (16.4g·m/m2) had a greater rate of reoperation than did the other patients (p = 0.0013). One patient died suddenly, and her mRVSWI was consistently high throughout her life.We established the mRVSWI as an index that integrates the pressure and volume load on the right ventricle. Our results indicate the utility of the mRVSWI for predicting patient prognosis after RVOTR.

Growth capacity of a Wharton's Jelly derived mesenchymal stromal cells tissue engineered vascular graft used for main pulmonary artery reconstruction in piglets.

Background: Surgical treatment of congenital heart defects affecting the right ventricular outflow tract (RVOT) often requires complex reconstruction and multiple reoperations due to structural degeneration and lack of growth of currently available materials. Hence, alternative approaches for RVOT reconstruction, which meet the requirements of biocompatibility and long-term durability of an ideal scaffold, are needed. Through this full scale pre-clinical study, we demonstrated the growth capacity of a Wharton's Jelly derived mesenchymal stromal cells (WJ-MSC) tissue engineered vascular graft used in reconstructing the main pulmonary artery in piglets, providing proof of biocompatibility and efficacy. Methods: Sixteen four-week-old Landrace pigs were randomized to undergo supravalvar Main Pulmonary Artery (MPA) replacement with either unseeded or WJ-MSCs-seeded Small Intestinal Submucosa-derived grafts. Animals were followed up for 6months by clinical examinations and cardiac imaging. At termination, sections of MPAs were assessed by macroscopic inspection, histology and fluorescent immunohistochemistry. Results: Data collected at 6months follow up showed no sign of graft thrombosis or calcification. The explanted main pulmonary arteries demonstrated a significantly higher degree of cellular organization and elastin content in the WJ-MSCs seeded grafts compared to the acellular counterparts. Transthoracic echocardiography and cardiovascular magnetic resonance confirmed the superior growth and remodelling of the WJ-MSCs seeded conduit compared to the unseeded. Conclusion: Our findings indicate that the addition of WJ-MSCs to the acellular scaffold can upgrade the material, converting it into a biologically active tissue, with the potential to grow, repair and remodel the RVOT.

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.

The Utility of Invengenx® Bovine Patch for Right Ventricular Outflow Tract (RVOT) Reconstruction and Augmentation in the Surgical Management of Tetralogy of Fallot (TOF): A Contemporary Study and Review of the Literature.

Background and objective Complex congenital heart diseases (CHDs), such as the tetralogy of Fallot (TOF), often warrant reconstruction and augmentation of the right ventricular outflow tract (RVOT). This procedure requires the use of both synthetic and natural materials. However, finding the ideal material for tissue implants can be challenging. Biological materials often face issues such as tissue degeneration, calcium deposition, antigenicity, rejection, shrinkage, and fibrosis. These issues can lead to complications such as stenosis and insufficiency, potentially requiring early reoperations. In light of this, this study aimed toinvestigate the effectiveness of the Invengenx® bovine patch for RVOT reconstruction and augmentation. Methods This was a retrospective observational studyconducted among eight children who underwent TOF correction cardiac surgery. Their demographic and clinical characteristics, intraoperative findings, and postoperative follow-up results at six months were collected from the hospital patient database. Results There were no deaths or complications in this study. We observed a significant reduction in the gradient across the pulmonary valve and the outflow tract at six months post-procedure. The analysis demonstrated that the Invengenx® bovine patch was successful and did not lead to any complications. Conclusions This study demonstrates the safety and efficacy of this engineered bovine pericardial patch (Invengenx®) as a cardiovascular substitute for surgical repair of both simple and more complex congenital cardiac defects.

Preliminary experience of transcatheter pulmonary valve replacement using domestic balloon-expandable valve

Objectives: To evaluate the feasibility and preliminary clinical results of transcatheter pulmonary valve replacement (TPVR) with the domestically-produced balloon-expandable Prizvalve system. Methods: This is a prospective single-center observational study. Patients with postoperative right ventricular outflow tract (RVOT) dysfunction, who were admitted to West China Hospital of Sichuan University from September 2021 to March 2023 and deemed anatomically suitable for TPVR with balloon-expandable valve, were included. Clinical, imaging, procedural and follow-up data were analyzed. The immediate procedural results were evaluated by clinical implant success rate, which is defined as successful valve implantation with echocardiography-assessed pulmonary regurgitation<moderate and peak trans-pulmonary pressure gradient<40 mmHg (1 mmHg=0.133 kPa). Results: A total of 5 patients were included, with 4 males, aged 14 to 37 years. The initial diagnosis included Tetralogy of Fallot (2 cases), truncus arteriosus (1 case), pulmonary atresia (1 case) and subaortic stenosis (1 case, prior Ross procedure). Four patients underwent RVOT reconstruction with homograft or artificial conduit, and one patient was treated with trans-annular patch technique. The indications of TPVR included RVOT obstruction and regurgitation (3 cases), isolated obstruction (1 case), and isolated regurgitation (1 case). Of the 4 patients with varying severity of ROVT obstruction, the average preprocedural peak jet velocity of RVOT was 3.5 m/s, and the average peak pressure gradient was 50.0 mmHg. Except for one patient, who had previously been implanted with a covered Cheatham-Platinum (CP) stent due to severe stenosis of the main pulmonary artery, other patients underwent pre-stenting with a covered CP stent before TPVR. Clinical implant success was achieved in all of the 5 patients, and there was no serious periprocedural complications. The average trans-pulmonary peak jet velocity and peak pressure gradient derived from postprocedural echocardiography was 2.3 m/s and 21.2 mmHg, respectively. All patients experienced significant symptom relief after the procedure. All patients completed 3-month follow-up, and 4 completed 6-month follow-up. There was no case of infectious endocarditis during follow-up. All patients were graded as NYHA functional class one at the latest follow-up. Conclusions: TPVR using the domestically-produced balloon-expandable Prizvalve system is safe and feasible for the treatment of patients with post-surgical RVOT dysfunction and suitable landing-zone anatomy. The safety, effectiveness, and long-term valve durability of the Prizvalve system deserve further research.

A Case of Cardiac Undifferentiated Pleomorphic Sarcoma With Right Ventricular Outflow Tract Obstruction.

Malignant tumors originating from the heart are extremely rare. Here, we report a case of severe right ventricular outflow tract (RVOT) stenosis in a 67 year-old woman caused by a massive intimal sarcoma that required venous-arterial extracorporeal membrane oxygenation to support systemic circulation. Surgical resection and RVOT reconstruction with tricuspid and pulmonary valve replacement were performed. The pathological diagnosis was cardiac undifferentiated pleomorphic sarcoma. Although the patient was discharged 65 days after surgery in good condition, she subsequently died from multiple metastases detected in the early phase after surgery.

A mid- and long-team follow-up study of the application of single-valved bovine pericardium patches in right ventricular outflow tract reconstruction.

Pulmonary regurgitation following right ventricular outflow tract (RVOT) reconstruction may cause right heart dysfunction and even right heart failure. Installation of a single valve at this time point can effectively reduce pulmonary regurgitation, thereby protecting right heart function. Here, we analyzed the outcomes and mid- and long-term follow-up data of patients undergoing single-valved bovine pericardium patch (svBPP) placement for reconstruction and explored the effectiveness and gaps of svBPP in preventing right heart failure. A retrospective analysis was performed on patients undergoing RVOT reconstruction using BalMonocTM svBPP from October 2010 to August 2020. The follow up procedures included outpatient visits and collection of outcomes. The cardiac ultrasound-related indicators during the follow-up visits included ejection fraction (EF), right ventricular end-diastolic diameter (EDD), pulmonary regurgitation, and pulmonary artery stenosis. The survival rates and reoperation-free rate were analyzed by Kaplan-Meier method. Patients includes tetralogy of Fallot, pulmonary atresia and other complex congenital heart disease. A total of 5 patients (5.7%) died during the perioperative period. Early complications included pleural effusion, cardiac insufficiency, respiratory insufficiency, chylothorax, and atelectasis, all of which were cured. After discharge, 83 patients (94.3%) were effectively followed up. During follow-up, 1 patient died and 1 patient underwent reoperation. The 1-, 5-, and 10-year survival rates were 98.8%, 98.8%, and 98.8%, respectively, and the reintervention-free rates for the same intervals were 98.8%, 98.8%, and 98.8%, respectively. The last follow-up ultrasound revealed severe pulmonary stenosis in 0 cases, moderate stenosis in 2 cases, mild stenosis in 7 cases, and no stenosis in 73 cases. Pulmonary regurgitation was not found in 12 patients; however, there were 2 cases of severe pulmonary regurgitation, 20 cases of moderate pulmonary regurgitation, and 48 cases of mild pulmonary regurgitation. As shown in the mid- and long-term follow-up studies, BalMonocTM svBPP has good performance in RVOT reconstruction. It can effectively eliminate or reduce pulmonary valve regurgitation and protect right heart function. Both réparation à l'Etage ventriculaire (REV) and the modified Barbero-Marcial procedure can bring growth potential and reduce reoperation rate.

Impact of right ventricular stiffness on discordance between hemodynamic parameter and regurgitant volume in patients with pulmonary regurgitation.

Accurate detection of significant pulmonary regurgitation (PR) is critical in management of patients after right ventricular (RV) outflow reconstruction in Tetralogy of Fallot (TOF) patients, because of its influence on adverse outcomes. Although pressure half time (PHT) of PR velocity is one of the widely used echocardiographic markers of the severity, shortened PHT is suggested to be seen in conditions with increased RV stiffness with mild PR. However, little has been reported about the exact characteristics of patients showing discrepancy between PHT and PR volume in this population. Echocardiography and cardiac magnetic resonance imaging (MRI) were performed in 74 TOF patients after right ventricular outflow tract (RVOT) reconstruction [32 ± 10 years old]. PHT was measured from the continuous Doppler PR flow velocity profile and PHT < 100 ms was used as a sign of significant PR. Presence of end-diastolic RVOT forward flow was defined as RV restrictive physiology. By using phase-contrast MRI, forward and regurgitant volumes through the RVOT were measured and regurgitation fraction was calculated. Significant PR was defined as regurgitant fraction ≥ 25%. Significant PR was observed in 54 of 74 patients. While PHT < 100 ms well predicted significant PR with sensitivity of 96%, specificity of 52%, and c-index of 0.72, 10 patients showed shortened PHT despite regurgitant fraction < 25% (discordant group). Tricuspid annular plane systolic excursion and left ventricular (LV) ejection fraction were comparable between discordant group and patients showing PHT < 100 ms and regurgitant fraction ≥ 25% (concordant group). However, discordant group showed significantly smaller mid RV diameter (30.7 ± 4.5 vs. 39.2 ± 7.3mm, P < 0.001) and higher prevalence of restrictive physiology (100% vs. 42%, P < 0.01) than concordant group. When mid RV diameter ≥ 32mm and presence of restrictive physiology were added to PHT, the predictive value was significantly improved (sensitivity: 81%, specificity: 90%, and c-index: 0.89, P < 0.001 vs. PHT alone by multivariable logistic regression model). Patients with increased RV stiffness and non-enlarged right ventricle showed short PHT despite mild PR. Although it has been expected, this was the first study to demonstrate the exact characteristics of patients showing discrepancy between PHT and PR volume in TOF patients after RVOT reconstruction.

Transthoracic Salus Valve Feasibility Study: Short-Term Outcomes of a Transcatheter Self-Expandable Pulmonary Valve

Objective: The size and morphology of the right ventricular outflow tract (RVOT) in patients suffering from long-term pulmonary regurgitation (PR) after native RVOT (NRVOT) reconstruction are important factors affecting the feasibility, safety, and effectiveness of transcatheter pulmonary valve replacement. The purpose of this study was to evaluate the feasibility, safety, and effectiveness of a transthoracic Salus valve (Balance Medical Technology Co., Ltd, Beijing, China) in patients with moderate-to-severe PR after NRVOT reconstruction. Methods: Patients with moderate-to-severe PR after NRVOT reconstruction were selected between June 2021 and November 2021 at Beijing Anzhen Hospital. Demographic data as well as preoperative, intraoperative, and follow-up data were reviewed. Results: Ten patients with moderate-to-severe PR after NRVOT reconstruction underwent physical examination, transthoracic echocardiography, and cardiovascular magnetic resonance imaging. Seven patients were selected for transthoracic Salus valve replacement. Six patients underwent implantation of the Salus valve successfully. One valve migrated and was embolized during recovery of the delivery device; the Salus valve was surgically explanted and sutured to the inner wall of the main pulmonary artery. At a mean follow-up of (5.5 ± 1.1) months, dysfunction or migration of the Salus valve embolism was not observed. Conclusions: This early feasibility study demonstrates the feasibility, safety, and effectiveness of transthoracic implantation of a Salus valve in patients with moderate-to-severe PR after NRVOT reconstruction. The short-term effectiveness is clear, medium and long-term effectiveness requires longer follow-up.

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).

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.

Anatomic Position and Durability of Polytetrafluoroethylene Conduit ≥18 mm: Single-Center Experience

BackgroundConduit longevity after right ventricular outflow tract (RVOT) reconstruction is determined by the interaction of different factors. We evaluated the relationship between conduit anatomic position and long-term durability among ≥18 mm polytetrafluoroethylene (PTFE) conduits. MethodsA single-institution RVOT reconstructions using a PTFE conduit ≥18 mm were identified. Catheter-based interventions or the need for conduit replacement were comparatively assessed between orthotopic vs heterotopic conduit position. Time to the first reintervention, censored by death, was compared between the groups. ResultsA total of 102 conduits were implanted in 99 patients, with a median age of 13.2 years (interquartile range [IQR] 8.9-17.8 years), median weight of 47 kg (IQR, 29-67 kg), and body surface area of 1.4 m2 (IQR, 1-1.7 m2). Overall, 50.9% (n = 52) of conduits were placed in an orthotopic position after the Ross procedure in congenital aortic valve abnormalities (80% [n = 36]). Tetrology of Fallot in 39% (n = 18), followed by truncus arteriosus with 33% (n = 15), were the most common in the heterotopic position. Trileaflet configuration was similar (67% vs 69%; P = .32) between the groups. Survival free from reintervention was 91% (95% CI, 79-97) and 88% (95% CI, 71-95) in the orthotopic and the heterotopic group, respectively, at 5 years, without differences in the Kaplan Meier curves (log-rank >.05). ConclusionsRVOT reconstruction with PTFE conduits ≥ 8 mm showed >90% conduit survival free from replacement in our cohort at 5 years. The anatomic position of the PTFE conduit does not seem to impact intermediate durability.

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.

A case of successful slide tracheoplasty for long-segment congenital tracheal stenosis in a neonate with a congenital diaphragmatic hernia and Fallot\u2019s tetralogy

BackgroundCongenital tracheal stenosis (CTS) is a rare and life-threatening airway disorder, which is often associated with cardiac malformations. Among them, neonatal symptomatic CTS with cardiac malformations has an extremely poor prognosis. In contrast to cardiac malformation, congenital diaphragmatic hernia (CDH) has rarely been associated with CTS. We report a neonatal case in which slide tracheoplasty and intracardiac repair were performed simultaneously for CTS and Fallot’s tetralogy (TOF).Case presentationAn infant with left CDH and Fallot's tetralogy (TOF) was born by cesarean section at 38 weeks of gestation. At the time of resuscitation, a 2.5 mm (ID) endotracheal tube could only be inserted just below the vocal cords. After repairing the CDH at 3 days of age, planned extubation was performed at 7 days of age. However, the patient required re-intubation due to life-threatening episodes after 2 days of the extubation. Enhanced CT revealed a long segment CTS from the upper trachea to the right bronchus (length of stenosis: 40 mm, minimum inner diameter: 2 mm). At 24 days of age, veno-arterial extracorporeal membrane oxygenation (ECMO) was introduced due to severe respiratory failure. At 28 days of age, slide tracheoplasty and palliative right ventricular outflow tract reconstruction (RVOTR) was performed with cardiopulmonary bypass (CPB). After tracheoplasty, a 3.5 mm tracheal (ID) tube could be placed in the reconstructed trachea in a patient with CTS. ECMO was completed 7 days after the operation. On the 17th day after the operation, he was extubated successfully. He was discharged 5 months after birth with home oxygenation therapy.ConclusionsWe reported the successful simultaneous correction of slide tracheoplasty and palliative RVOTR for a neonate with CDH. ECMO was used for respiratory management before and after surgery.

Clinical Results of Decellularized Pulmonary Allografts for Right Ventricular Outflow Tract reconstruction during Ross Procedure. Where are we today?

Sir Donald N. Ross established a new era to treat aortic valve disease by introducing the Ross procedure in 1967. The original technique was complex by implanting the pulmonary valve subcoronary into the aortic root with excellent long-term results. The limited part of this specific approach however, was meanly the right ventricular outflow tract (RVOT) reconstruction. Today, the golden standard is the use of a cryopreserved pulmonary allograft, however disadvantageous such as availability and immunogenic response can eventually lead to structural valve deterioration. Tissue engineering could help to create a valve with an excellent durability including remodelling, regeneration and growth potential for RVOT reconstruction. This article reflex a recent literature overview on clinical available solutions of correcting the RVOT by the use of decellularized pulmonary allografts.

The fate of the fresh autologous pericardium after right ventricular outflow tract reconstruction.

Introduction: The autologous pericardium, treated or fresh, is used in reconstructive cardiovascular surgery. We aimed to describe the features of fresh pericardium utilized in right ventricular outflow tract (RVOT) reconstruction, years after the initial surgery. Methods: This cross-sectional study was performed on 72 patients (65.3% male, mean age =18.68 ± 9.63 y) with a history of RVOT reconstruction with the fresh autologous pericardium who underwent reoperation. During the surgery, a 1 × 1 cm sample was cut from the previous pericardial patch, and hematoxylin and eosin (H & E), Masson’s trichrome, and immunohistochemistry (IHC) staining was conducted. All the stained slides were evaluated,and the descriptive results were explained. Results: The mean follow-up duration was 13.48 ± 7.38 years. In preoperative evaluations,53 (73.6%) patients exhibited no RVOT dilatation, 17 (23.6%) showed mild RVOT dilatation,and 2 (2.8%) had RVOT aneurysms. The H & E staining revealed no calcification in 80.55%(58/72), mild calcification in 9.72% (7/72), and moderate calcification in 9.72% (7/72) of the total samples. None of the specimens demonstrated a marked calcification. All the samples were positive for CD31, CD34, smooth muscle alpha-actin, and von Willebrand factor in IHC. In Masson’s trichrome staining, on average, 64.74% (±18.61) of the tissue sections contained collagen fibers. Conclusion: The fresh autologous pericardium, utilized for RVOT reconstruction, showed viability, growth potential, positivity for endothelial cell markers, vascular differentiation,insignificant calcification, and no stenosis at long-term follow-up. We would, therefore, suggest it as a suitable choice for such reconstructive operations. Moreover, its usage during total correction of tetralogy of Fallot could be safe, feasible, and durable.

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.