Right Ventricular Outflow Tract Reconstruction With the Bovine Jugular Vein Graft: 5 Years’ Experience With 133 Patients

Endocarditis in Bovine Vein Grafts in the Pulmonary Position Placed Surgically & Percutaneously

Background: Infective endocarditis (IE) is one of the major complications following pulmonary valve replacement (PVR). This analysis hopes to evaluate the incidence, outcomes and possible risk factors of IE associated with trans-catheter and surgical placement of a bovine jugular vein (BJV) graft in the pulmonary position. Methods: In this single-center retrospective study, all records of trans-catheter and surgical PVR from 3/2010 to 12/2019 were reviewed. IE was defined as positive blood cultures, with vegetations seen on echocardiography or sudden increase in peak gradient across the valve or vegetations confirmed at time of valve replacement. Poor dental hygiene:1.dental procedures without S.B.E prophylaxis AND/OR 2.one or more dental cavities, caries, dental abscess. Results: 165 patients had PVR with BJV:107 trans-catheter and 63 surgical. 7%(12/170) of PVRs developed IE(catheter:n = 10, surgery:n = 2) at a median time from valve placement of 38 months. The incidence of IE in the catheter group:3-per-100patient-years and in surgical group:1-per-100patient-years. Multivariate cox regression showed that poor dental hygiene was significantly associated with IE [HR(95% CI):16.9(4.35-66.2)](p value <.001). Kaplan-Meier curves showed a significant difference in freedom from IE between patients with poor and appropriate dental hygiene (p value<.001). Conclusions: There is a 7% incidence of IE with the use of BJV grafts in the pulmonary position at mid-term follow-up. Though the rate in catheter placed BJV seems 3x higher than surgically placed ones, their cohorts are quite different making this comparison flawed. Poor dental hygiene is a strong predictor for post-operative IE and offers a significant opportunity for lowering the rate of infective endocarditis.

Application of Homograft Valved Conduit in Cardiac Surgery

Valved conduits often correct the blood flow of congenital heart disease by connecting the right ventricle to the pulmonary artery (RV-PA). The homograft valved conduit was invented in the 1960s, but its wide application is limited due to the lack of effective sterilization and preservation methods. Modern cryopreservation prolongs the preservation time of homograft valved conduit, which makes it become the most important treatment at present, and is widely used in Ross and other operations. However, homograft valved conduit has limited biocompatibility and durability and lacks any additional growth capacity. Therefore, decellularized valved conduit has been proposed as an effective improved method, which can reduce immune response and calcification, and has potential growth ability. In addition, as a possible substitute, commercial xenograft valved conduit has certain advantages in clinical application, and tissue engineering artificial valved conduit needs to be further studied.

Mid-term outcomes of Contegra implantation for the reconstruction of the right ventricular outflow tract to proximal branch pulmonary arteries: Japan multicentre study

OBJECTIVES

To reveal the mid-term outcomes of Contegra implantation for the reconstruction of the right ventricular outflow tract to proximal branch pulmonary arteries in a multicentre study.

METHODS

Between April 2013 and December 2019, 178 Contegra conduits were implanted at 5 Japanese institutes. The median age and body weight at operation were 16 months (25th-75th percentile: 8-32) and 8.3 kg (6.4-10.6). Sixteen patients were neonates (9.0%). Selected conduit sizes were 12 mm in 28 patients (15.7%), 14 mm in 67 patients (37.6%), 16 mm in 66 patients (37.1%), 18 mm in 5 patients (2.8%) and <12 mm in 12 patients (6.7%). Fifty-six grafts (31.4%) were ring supported. Proximal branch pulmonary arteries were concomitantly augmented in 85 patients (47.5%). Follow-up was completed in all patients and the median follow-up period was 3.1 years (1.3-5.1).

RESULTS

The overall, conduit explantation-free and conduit infection-free survival rates at 5 years were 91.3%, 71.0% and 83.7%, respectively. Infection (P = 0.009) and common arterial trunk (P = 0.024) were risk factors for explantation. Conduit durability was shorter in smaller one (P < 0.001). Catheter interventions (for conduit to proximal branch pulmonary artery)-free survival rates at 5 years was 52.9%; however, need for catheter interventions was not a risk factor for conduit explantation.

CONCLUSIONS

Mid-term outcomes of reconstruction of the right ventricular outflow tract to the proximal branch pulmonary arteries with Contegra were acceptable. The need for explantation over time was higher in smaller conduits. Conduit infection was a strong risk factor for conduit explantation. Frequently and repeated catheter interventions effectively extended the conduit durability.

Right ventricular outflow reconstruction with handmade valve conduit - A short experience from a developing country. Case series

Objectives

Right ventricular outflow tract continuity abnormalities are one of the most commonly encountered entities in the field of congenital cardiac surgery. Various strategies including homograft, valve conduit, Contegra are used to restore continuity between right ventricle and pulmonary artery. In countries like Pakistan these may not be easily available and affordable. We report the experience of our short observational study of using a handmade trileaflet valve conduit to reconstruct the right ventricular outflow tract.

Methodology

From September 2015 to December 2016, a total of 15 patients with different congenital heart diseases underwent open-heart surgery at our institute. Restoration of right ventricular to pulmonary artery continuity was achieved using handmade valve conduit utilizing bovine pericardium and thin sheet PTFE sheets (0.1 mm) as conduit and valve respectively.

Results

Patients ranged from 1 to 16 years. Seven patients had previous palliation including 4 blalock taussig (BT) Shunts and 3 pulmonary artery (PA) banding. Postoperative complications were observed in 4 patient including 2 in hospital deaths and 2 required interventions. One patient developed aneurysm at RV- conduit junction requiring surgical repair and the other underwent conduit dilatation for moderate to severe stenosis (gradient 60 mmHg). No significant regurgitation was observed in this series. Overall postoperative gradients were stable with mean gradient 25.3 mmHg (8 mmhg - 60 mmHg).

Conclusion

The use of handmade valve conduits has acceptable morbidity and mortality. These are cost effective alternatives in this part of the world, where well-established conduits have cost implications and uncertain availability.

Reconstruction of the pulmonary posterior wall using in situ autologous tissue for the treatment of pulmonary atresia with ventricular septal defect

Background

To evaluate the early and mid-term results of pulmonary trunk reconstruction using a technique in which autogenous tissue is preserved in situ in pulmonary atresia patients with a ventricular septal defect (PA-VSD).

Methods

The pulmonary artery was reconstructed using autogenous tissue that had been preserved in situ and a bovine jugular venous patch in 24 patients who were diagnosed with PA-VSD (the observation group). The traditional operation using a bovine jugular venous conduit was performed in 40 other cases of PA-VSD (the control group).

Results

In the observation group, all patients survived and recovered successfully without complications. Follow-up echocardiography 2–10 years after the procedure showed that the reconstructed right ventricular outflow tract (RVOT) and pulmonary artery were patent, showing no evidence of flow obstruction. Only mild regurgitation of the bovine jugular vein valve was observed. In the control group, early postoperative death occurred in two cases. Another two patients had obstruction of the anastomotic stoma and underwent conduit replacement surgery within 2 weeks of the initial procedure. During the 2–10 years of follow-up care, six patients presented with valvular stenosis of the BJVC, with a pressure gradient of more than 50 mmHg.

Conclusions

The technique for preserving autogenous tissue to reconstruct the pulmonary posterior wall is a satisfactory method for treating PA-VSD.

Current status of right ventricular outflow tract reconstruction: complete translation of a review article originally published in Kyobu Geka 2014;67:65-77

Right ventricular outflow tract (RVOT) reconstruction is becoming more prevalent as the number of adult patients who require repeated surgery long after definitive repair of congenital heart defects during childhood has increased. Early primary repair and annulus-preserving surgery have been the two current strategies of RVOT reconstruction from the viewpoint of timing and indications for surgical intervention; however, the long-term outcomes of both procedures remain unknown. Although various materials have been used for pulmonary valve replacement during RVOT reconstruction, deficient durability due primarily to immunological rejection frequently arises, particularly when implanted into young patients. A multicenter study in Japan showed that the clinical outcomes of expanded polytetrafluoroethylene (ePTFE) valved patches/conduits that we developed and manufactured comprised an excellent alternative material for RVOT reconstruction. Such enhanced outcomes might have partly been attributable to the biocompatibility and low antigenicity of ePTFE, and also to the fluid dynamic properties arising from the structural characteristics of a bulging sinus and a fan-shaped valve. However, numerous issues concerning RVOT reconstruction, such as indications for and the timing of definitive repair, as well as the choice of materials for pulmonary valve replacement, must be resolved to achieve better patient prognoses and quality of life. This review describes recent surgical strategies and outstanding issues associated with RVOT reconstruction.

MR and CT imaging of pulmonary valved conduits in children and adolescents: normal appearance and complications

BACKGROUND

The Contegra® is a conduit made from the bovine jugular vein and then interposed between the right ventricle and the pulmonary artery. It is used for cardiac malformations in the reconstruction of right ventricular outflow tract.

OBJECTIVE

To describe both normal and pathological appearances of the Contegra® in radiological imaging, to describe imaging of complications and to define the role of CT and MRI in postoperative follow-up.

MATERIALS AND METHODS

Forty-three examinations of 24 patients (17 boys and 7 girls; mean age: 10.8 years old) with Contegra® conduits were reviewed. Anatomical description and measurements of the conduits were performed. Pathological items examined included stenosis, dilatation, plicature or twist, thrombus or vegetations, calcifications and valvular regurgitation. Findings were correlated to the echographic gradient through the conduit when available.

RESULTS

CT and MR work-up showed Contegra® stenosis (n = 12), dilatation (n = 9) and plicature or twist (n = 7). CT displayed thrombus or vegetations in the Contegra® in three clinically infected patients. Calcifications of the conduit were present at CT in 12 patients and valvular regurgitation in three patients. The comparison between CT and/or MR results showed a good correlation between the echographic gradient and the presence of stenosis in the Contegra®.

CONCLUSION

CT and MR bring additional information about permeability and postoperative anatomy especially when echocardiography is inconclusive. Both techniques depict the normal appearance of the conduit, and allow comparison and precise evaluation of changes in the postoperative follow-up.

An increased incidence of conduit endocarditis in patients receiving bovine jugular vein grafts compared to cryopreserved homograft for right ventricular outflow reconstruction

BACKGROUND

We compared the outcome of patients receiving bovine jugular vein grafts versus cryopreserved homografts for right ventricular outflow tract reconstruction.

METHODS

Between 2000 and 2012, 379 conduits (244 bovine jugular vein grafts, 135 homografts) were implanted in 298 patients (median age 50 months) with a median follow-up of 3.4 years.

RESULTS

Freedom from reoperation at 1, 5, and 7 years was 96.3%, 79.3%, and 64.2% after bovine jugular vein graft and 94.6%, 75.7%, and 68.6% after homograft insertion (p = 0.086). There were 24 cases of endocarditis, 23 associated with bovine jugular vein grafts (9.4%) and 1 associated with a homograft (0.7%; p < 0.001) at median follow-up of 44 months (range, 15 days to 10 years) after conduit implantation. After endocarditis, 15 of 24 conduits were replaced. Three patients had recurrent endocarditis in the revised conduit. Multivariate logistic regression analysis showed age less than 3 years and endocarditis to be significant risk factors associated with conduit replacement. Age more than 3 years and bovine jugular vein grafts were significant risk factors for graft endocarditis. Patients more than 3 years of age at bovine jugular vein graft implantation had significantly lower freedom from reoperation (p = 0.01).

CONCLUSIONS

Compared with homograft conduits, the use of bovine jugular vein grafts for right ventricular outflow tract reconstruction was associated with a significantly higher incidence of bacterial endocarditis and conduit deterioration in older children at our institution. That may influence decision making regarding conduit choice for right ventricular outflow tract reconstruction. Patients and practitioners should be aware of the late risks of bacterial endocarditis after bovine jugular vein graft implantation.

Options for prosthetic pulmonary valve replacement

This article reviews current data on various prostheses utilized for pulmonary valve replacement. Durability data is reviewed and risk factors for deterioration are examined. Finally, the choice of prosthesis should be tailored to the specific clinical scenario based on existing data regarding durability and risk factors.

Decellularized and photooxidatively crosslinked bovine jugular veins as potential tissue engineering scaffolds

Decellularization means and altering crosslinking approaches were two promising alternatives for glutaraldehyde fixation to biological tissues. Bovine jugular veins (BJVs) were decellularized by a multi-step detergent-enzymatic extraction method, then photooxidatively crosslinked. Gross and histological integrity of which was retained. Ultrastructures showed integrity of collagen fibrils and elastic fibers, and a basement membrane free luminal surface. Mechanical strength test and tissue protein extraction assay demonstrated their tissue stability. After being pre-coated with gelatin, collagen IV and fibronectin, cultured human umbilical vein endothelial cells were planted in the luminal surface of decellularized plus photooxidized BJV patches for seven days. Endothelial cells were denser in pre-coated patches than in uncoated controls. A rat subcutaneous implantation model revealed more resistance against in vivo degradation for further crosslinked BJV patches than decellularized patches at 12-week retrieval. Host cells were all layer repopulated for both. Histological examination and content assay demonstrated collagen and glycosaminoglycan components synthesis for decellularized plus photooxidized BJV patches. Decellularized and photooxidatively crosslinked BJV patches possess tissue integrity, excellent in vitro and in vivo tissue stability and repopulation patterns. Thus, they have potentials as tissue engineering scaffolds in future cardiovascular surgery.

Ten-year experience with handmade trileaflet polytetrafluoroethylene valved conduit used for pulmonary reconstruction

OBJECTIVE

The objective of this study was to investigate the results of handmade polytetrafluoroethylene trileaflet conduits implanted in the pulmonary position since 1997.

METHODS

One hundred thirty-nine patients underwent pulmonary reconstruction with a polytetrafluoroethylene conduit. Conduit function was investigated by means of review of serial echocardiographic studies.

RESULTS

Mean age and body weight were 12.7 +/- 12.0 years and 30.9 +/- 20.6 kg. Mean size of the conduit was 21.0 +/- 3.8 mm (12-28 mm). The z score of the conduit was +0.5 +/- 0.8 for patients older than 15 years (n = 43), +1.2 +/- 0.7 for patients 5 to 15 years old (n = 48), and +2.4 +/- 0.5 for patients younger than 5 years (n = 48). Conduits were used for the Ross procedure in 21 patients and for repair of complex congenital heart disease in 118 patients. There were 3 (2.2%) in-hospital deaths and 1 late death. Four patients required conduit explantation because of pulmonary artery distortion at a distal anastomotic site (interval, 1.2 years), infection of the polytetrafluoroethylene valve (interval, 1.6 years), midportion angulation of the conduit (interval, 4.9 years), and conduit compression by the ascending aorta (interval, 5.4 years). Estimated freedom from conduit explantation was 88.0% +/- 6.8%, and pulmonary insufficiency was less than or equal to mild in 75.0% at 10 years. All valves maintained their motion, and the mean estimated pressure gradient across the conduit was 19.6 +/- 11.9 mm Hg at 5 years and appeared to reach a plateau thereafter. The pressure gradient across the conduit was 14.2 +/- 8.0 mm Hg at 3 years (P = .0127) and 18.1 +/- 7.5 mm Hg at 7 years (P = .0208).

CONCLUSIONS

Polytetrafluoroethylene conduits represent a valid option and reliable alternative to homograft and xenograft implantation for pulmonary reconstruction.