Risk factors for development of endocarditis and reintervention in patients undergoing right ventricle to pulmonary artery valved conduit placement

Valved Conduits for Right Ventricular Outflow Tract Reconstruction: A Review of Current Technologies and Future Directions

The need for right ventricular outflow tract reconstruction is common and growing in congenital heart surgery given expanding indications for the repair of congenital as well as acquired heart disease. Various valved conduit options currently exist including homografts, xenograft pulmonary valved conduits (Contegra™), and porcine valved conduits. The major limitation for all conduits is implant durability, which requires reoperation. Currently, cryopreserved homografts are often used given their superiority shown in long-term data. Significant limitations remain in the cost and availability of the graft, particularly for smaller sizes. Contegra conduits are available in a variety of sizes. Nonetheless, the data regarding long-term durability are less robust and studies comparing durability with homografts have been conflicting. Additionally, there is concern for increased rates of late endocarditis in this conduit. Porcine valved conduits offer a reliable option but are limited by structural valve degeneration associated with all types of bioprosthetic heart valve replacements. New developments in the field of tissue engineering have produced promising bio-restorative valved conduits that may overcome many of the limitations of previous conduit technologies. These remain in the early stages of clinical testing. This review summarizes the clinical data surrounding the conduits used most commonly in clinical practice today and explores emerging technologies that may bring us closer to developing the ideal conduit.

Long-Term Management of Right Ventricular Outflow Tract Dysfunction in Repaired Tetralogy of Fallot: A Scientific Statement From the American Heart Association

Right ventricular outflow dysfunction, manifesting as stenosis, regurgitation, or both, is nearly universal in patients with repaired tetralogy of Fallot, precipitating a complex pathophysiological cascade that leads to increasing rates of morbidity and mortality with advancing age. As the number of adolescent and adult patients with repaired tetralogy of Fallot continues to grow as a result of excellent survival during infancy, the need to improve late outcomes has become an urgent priority. This American Heart Association scientific statement provides an update on the current state of knowledge of the pathophysiology, methods of surveillance, risk stratification, and latest available therapies, including transcatheter and surgical pulmonary valve replacement strategies, as well as management of life-threatening arrhythmias. It reviews emerging evidence on the roles of comorbidities and patient-reported outcomes and their impact on quality of life. In addition, this scientific statement explores contemporary evidence for clinical choices such as transcatheter or surgical pulmonary valve replacement, discusses criteria and options for intervention for failing implanted bioprosthetic pulmonary valves, and considers a new approach to determining optimal timing and indications for pulmonary valve replacement.

Advancements and Challenges in the Management of Prosthetic Valve Endocarditis: A Review

Prosthetic valve endocarditis (PVE) is the medical term used to describe a focus of infection involving a valvular substitute within the heart. It is a significant concern in the field of cardiology, and the epidemiology of PVE has seen notable developments over the last five decades. The disease currently affects an older demographic and is becoming increasingly prevalent in patients with transcatheter-implanted valves. It is imperative that we urgently address the significant challenges posed by PVE. It is a disease that has a wide range of potential aetiologies, clinical presentations, and courses. In developed countries, Staphylococcus aureus is now the predominant causative organism, resulting in an aggressive form of disease that frequently afflicts vulnerable or elderly populations. However, it is clear that Enterococcus species present a significant challenge in the context of PVE following TAVR procedures, given their elevated prevalence. The 2023 Duke/International Society for Cardiovascular Infectious Diseases infective endocarditis diagnostic criteria now include significant developments in microbiological and image-based techniques for diagnostic purposes, specifically the incorporation of fluorine-18 fluorodeoxyglucose positron emission tomography and computed tomography. These developments unequivocally enhance the diagnostic sensitivity for PVE, while maintaining the specificity. They do so in accordance with the results of studies conducted specifically for the purpose of validation. The lack of rigorous scientific studies and a shortage of funding and resources for research have led to a significant gap in our understanding. Randomized controlled trials could provide invaluable insight and guidance for clinical practice, but they are missing, which represents a major gap. It is clear that there is an urgent need for more research. PVE is a life-threatening condition that must be handled by a multidisciplinary endocarditis team at a cardiac centre in order to improve outcomes. The emergence of innovative surgical techniques has empowered clinicians to steer more patients away from surgical procedures, despite the presence of clear indications for them. A select group of patients can now complete parenteral or oral antimicrobial treatment at home. Additionally, antibiotic prophylaxis is the best option for individuals with prosthetic valves who are going to have invasive dental procedures. These individuals should be given antibiotics beforehand.

Durability of Aortic Homografts in Pulmonary Atresia and Major Aortopulmonary Collateral Arteries

Objectives: It is well-known that right ventricle-to-pulmonary artery homograft conduit durability is worse for smaller conduits and smaller/younger patients. However, there is limited literature on age and conduit-size specific outcomes, or on the role of conduit oversizing. Methods: Patients diagnosed with tetralogy of Fallot and major aortopulmonary collateral arteries undergoing right ventricular outflow tract (RVOT) reconstruction with a valved aortic homograft conduit from November 2001 through March 2023, at our institution were included. Conduits were grouped and evaluated by diameter, diameter Z-score, and patient age at implant. The primary time-related outcome was freedom from RVOT reintervention. Factors associated with freedom from time-related outcomes were assessed with univariable Cox regression analysis. Results: A total of 863 RVOT conduits were implanted in 722 patients. On multivariable analysis, younger age, male sex, Alagille syndrome, smaller diameter of the conduit, and smaller Z-score were associated with shorter freedom from reintervention. Among patients with smaller diameter conduits, larger Z-scores were associated with longer freedom from conduit reintervention (P < .001). Transcatheter interventions were commonly used to extend conduit lifespan across ages and conduit sizes. Conclusions: Larger conduit diameter, older age, and higher conduit Z-score were associated with longer freedom from reintervention in patients undergoing RVOT reconstruction in this cohort. Oversizing of conduits, even beyond a Z-score of 4, is generally appropriate.

Performance and Failure of Right Ventricle to Pulmonary Artery Conduit in Congenital Heart Disease

Surgical implantation of a right ventricle to pulmonary artery (RV-PA) conduit is an important component of congenital heart disease (CHD) surgery, but with limited durability, leading to re-intervention. The present single-center, retrospective, cohort study reports the results of surgically implanted RV-PA conduits in a consecutive series of children and adults with CHD. Patients with CHD referred for RV-PA conduit surgical implantation (from October 1997 to January 2022) were included. The primary outcome was conduit failure, defined as a peak gradient above 64 mm Hg, severe regurgitation, or the need for conduit-related interventions. Longitudinal echocardiographic studies were available for mixed-effects linear regression analysis. A total of 252 patients were initially included; 149 patients were eligible for follow-up data collection. After a median follow-up time of 49 months, the primary study end point occurred in 44 (29%) patients. A multivariable Cox regression model identified adult age (>18 years) at implantation and pulmonary homograft implantation as protective factors (hazard ratio 0.11, 95% confidence interval [CI] 0.02 to 0.47 and hazard ratio 0.34, 95% CI 0.16 to 0.74, respectively). Fever within 7 days of surgical conduit implantation was a risk factor for early (within 24 months) failure (odds ratio 4.29, 95% CI 1.41 to 13.01). Long-term use of oral anticoagulants was independently associated with slower progression of peak echocardiographic gradient across the conduits (mixed-effects linear regression p = 0.027). In patients with CHD, the rate of failure of surgically implanted RV-PA conduits is higher in children and after nonhomograft conduit implantation. Early fever after surgery is a strong risk factor for early failure. Long-term anticoagulation seems to exert a protective effect.

Handmade Bicuspid Valved Polytetrafluoroethylene Conduit for Right Ventricular Outflow Tract Reconstruction

Background: Excellent outcomes of right ventricle to pulmonary artery conduits with polytetrafluoroethylene (PTFE) valves have been reported. The purpose of this study was to analyze the short-term results of our handmade PTFE bicuspid valved conduit (VC) for right ventricular outflow tract reconstruction. Methods: Between September 2019 and May 2023, bicuspid PTFE-VC was implanted in 17 patients at a median age of 2.5 years (range, 3 months to 13.6 years). The PTFE-VC was fashioned from a commercially available PTFE tube graft (14 mm in three patients, 16 mm in three patients, 18 mm in one patient, 20 mm in three patients, and 22 mm in seven patients) and 0.1 mm thick PTFE membrane for the leaflet material. Valve function was assessed by echocardiogram after the implantation. The conduit reoperation and the conduit dysfunction were analyzed. There were no early deaths, but there was one late death. Results: There were no postoperative in-hospital deaths. Follow-up echocardiograms were available for 14 of 17 patients. The median follow-up was 21 months (range, 7-49 months). Conduit stenosis was none or trivial in 11 patients while it was mild in two and moderate in one patient and severe in 0 patients. Conduit insufficiency was mild or trivial in all 14 patients. By the end of the study period, freedom from reoperation/reintervention was 100%. There were no episodes of aneurysmal dilatation of the conduit or endocarditis. Conclusions: Handmade bicuspid PTFE VC shows good short-term outcome, with no significant valve dysfunction and no reintervention. A longer follow-up is necessary to evaluate the long-term advantages of using the handmade bicuspid PTFE VC.

Imaging in Infective Endocarditis-Current Opinions and Trends in Cardiac Computed Tomography

Infective endocarditis is a rare disease with an increasing incidence and an unaltered high mortality rate, despite medical development. Imaging plays an integrative part in the diagnosis of infective endocarditis, with echocardiography as the initial diagnostic test. Research data in the utility of cardiac computed tomography (CCT) in the diagnostic algorithm of IE are rising, which indicates its importance in detection of IE-related lesion along with the exclusion of coronary artery disease. The latest 2023 European Society of Cardiology Guidelines in the management of IE classified CCT as class of recommendation I and level of evidence B in detection of both valvular and paravalvular lesions in native and prosthetic valve endocarditis. This review article provides a comprehensive and contemporary review of the role of CCT in the diagnosis of IE, the optimization of acquisition protocols, the morphology characteristics of IE-related lesions, the published data of the diagnostic performance of CCT in comparison to echocardiography as the state-of-art method, as well as the limitations and future possibilities.

The infected right ventricular outflow tract in children and adults with congenital heart disease

Abnormalities of the right ventricular outflow tract are common within the spectrum of congenital heart disease. Reconstruction of this outflow with or without the use of prosthetic material forms an integral part of many surgical procedures. Consequently, this part of the heart constitutes an important locus for infective endocarditis. Focused literature on infective endocarditis of the right ventricular outflow is sparse. This narrative review therefore attempts to collate the currently available data on a subject that is gaining importance because of the increasing numbers of surgical and catheter-based interventions on the right ventricular outflow.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-024-01748-z.

The Clinical Challenge of Prosthetic Valve Endocarditis: JACC Focus Seminar 3/4

During the past 6 decades, there have been numerous changes in prosthetic valve endocarditis (PVE), currently affecting an older population and increasing in incidence in patients with transcatheter-implanted valves. Significant microbiologic (molecular biology) and imaging diagnostic (fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography) advances have been incorporated into the 2023 Duke-International Society for Cardiovascular Infectious Diseases infective endocarditis diagnostic criteria, thus increasing the diagnostic sensitivity for PVE without sacrificing specificity in validation studies. PVE is a life-threatening disease requiring management by multidisciplinary endocarditis teams in cardiac centers to improve outcomes. Novel surgical options are now available, and an increasing set of patients may avoid surgical intervention despite indication. Selected patients may complete parenteral or oral antimicrobial treatment at home. Finally, patients with prosthetic valves implanted surgically or by the transcatheter approach are candidates for antibiotic prophylaxis before invasive dental procedures.

Outcomes after Biventricular Repair Using a Conduit between the Right Ventricle and Pulmonary Artery in Infancy

Background

This study investigated the outcomes of biventricular repair using right ventricle to pulmonary artery (RV-PA) conduit placement in patients aged <1 year.

Methods

Patients aged <1 year who underwent biventricular repair using an RV-PA conduit between 2011 and 2020 were included in this study. The outcomes of interest were death from any cause, conduit reintervention, and conduit dysfunction (peak velocity of ≥3.5 m/sec or moderate or severe regurgitation).

Results

In total, 141 patients were enrolled. The median age at initial conduit implantation was 6 months. The median conduit diameter z-score was 1.3. The overall 5-year survival rate was 89.6%. In the multivariable analysis, younger age (p=0.006) and longer cardiopulmonary bypass time (p=0.001) were risk factors for overall mortality. During follow-up, 61 patients required conduit reintervention, and conduit dysfunction occurred in 68 patients. The 5-year freedom from conduit reintervention and dysfunction rates were 52.9% and 45.9%, respectively. In the multivariable analysis, a smaller conduit z-score (p<0.001) was a shared risk factor for both conduit reintervention and dysfunction. Analysis of variance demonstrated a nonlinear relationship between the conduit z-score and conduit reintervention or dysfunction. The hazard ratio was lowest in patients with a conduit z-score of 1.3 for reintervention and a conduit z-score of 1.4 for dysfunction.

Conclusion

RV-PA conduit placement can be safely performed in infants. A significant number of patients required conduit reintervention and had conduit dysfunction. A slightly oversized conduit with a z-score of 1.3 may reduce the risk of conduit reintervention or dysfunction.

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.

Unmet Clinical Needs for Transcatheter Pulmonary Valves

A common feature of congenital heart disease is the presence of right ventricular outflow tract (RVOT) obstruction that can range from mild to severe and can lead to atresia of the pulmonary valve, in extreme conditions. RVOT abnormalities can frequently be corrected surgically or via interventional means. However, most of these patients will ultimately develop pulmonary valve insufficiency and eventual right ventricular dilation, which will require a pulmonary valve replacement at some point in their life to mitigate the detrimental effects of pulmonary valve regurgitation (PVR) on the right ventricle (RV). The evolution from the studies done by Philip Bonhoeffer to implant a pulmonary valve via transcatheter means, have provided a bedrock for transcatheter pulmonary valve replacement (TPVR). Yet, several areas of unmet need for a demographic of patients still exist. Here, we discuss the clinical unmet needs in children under 20 Kg and expand the use of hybrid and other TPVR approaches along with the current indications and contraindications for pulmonary valve replacement. The constraints and limitations from commercially available pulmonary valves will be discussed from a clinical standpoint. Finally, we explore the use of hybrid and periventricular delivery of transcatheter pulmonary valves in younger patients.

Cardiac Computed Tomographic Angiography Evaluation of Right Ventricle-Pulmonary Artery Conduits with Surgical Correlation

Right ventricle-pulmonary artery (RV-PA) conduits are used in the treatment of certain congenital heart disease (CHD). RV-PA conduit complications might develop over time and require intervention. To evaluate how well cardiac computed tomographic angiography (CCTA) performs compared to transthoracic echocardiography (TTE) in evaluating RV-PA conduit complications by using surgical findings as the reference standard. A retrospective chart review of all patients over a 5-year period who underwent CCTA for RV-PA conduit evaluation was performed. Patient demographics and clinical data were recorded. Preoperative CCTA and TTE findings were compared to the operative findings for concordance or discordance. Forty-one patients were included, 51% females. The complications were conduit stenosis (28.68%), infection (7.17%) and aneurysm/pseudoaneurysm (6.15%). TTE and CCTA were consistently able to visualize focal conduit stenosis (96%). The greatest discrepancy between TTE and CCTA was in evaluating for aneurysm/pseudoaneurysm, where TTE detected only 2/6 (33%) compared to CCTA which detected 6/6 (100%) of the cases. However, TTE was slightly better at detecting conduit infection (3/7, 43%) compared to CCTA (2/7, 29%). Note that 5 out of 7 patients with endocarditis had bovine jugular graft. CCTA and TTE provide similar diagnostic accuracy evaluating certain types of RV-PA conduit complications. However, certain complications were only visualized on CCTA or TTE making both modalities complementary to each other during diagnostic evaluation.

Infective Endocarditis Risk with Melody versus Sapien Valves Following Transcatheter Pulmonary Valve Implantation: A Systematic Review and Meta-Analysis of Prospective Cohort Studies

BACKGROUND

Transcatheter pulmonary valve implantation (TPVI) is an effective non-surgical treatment method for patients with right ventricle outflow tract dysfunction. The Medtronic Melody and the Edwards Sapien are the two valves approved for use in TPVI. Since TPVI patients are typically younger, even a modest annual incidence of infective endocarditis (IE) is significant. Several previous studies have shown a growing risk of IE after TPVI. There is uncertainty regarding the overall incidence of IE and differences in the risk of IE between the valves.

METHODS

A systematic search was conducted in the MEDLINE, EMBASE, PubMed, and Cochrane databases from inception to 1 January 2023 using the search terms 'pulmonary valve implantation', 'TPVI', or 'PPVI'. The primary outcome was the pooled incidence of IE following TPVI in Melody and Sapien valves and the difference in incidence between Sapien and Melody valves. Fixed effect and random effect models were used depending on the valve. Meta-regression with random effects was conducted to test the difference in the incidence of IE between the two valves.

RESULTS

A total of 22 studies (including 10 Melody valve studies, 8 Sapien valve studies, and 4 studies that included both valves (572 patients that used the Sapien valve and 1395 patients that used the Melody valve)) were used for the final analysis. Zero IE incidence following TPVI was reported by eight studies (66.7%) that utilized Sapien valves compared to two studies (14.3%) that utilized Melody valves. The pooled incidence of IE following TPVI with Sapien valves was 2.1% (95% CI: 0.9% to 5.13%) compared to 8.5% (95% CI: 4.8% to 15.2%) following TPVI with Melody valves. Results of meta-regression indicated that the Sapien valve had a 79.6% (95% CI: 24.2% to 94.4%, p = 0.019; R2 = 34.4) lower risk of IE incidence compared to the Melody valve.

CONCLUSIONS

The risk of IE following TPVI differs significantly. A prudent valve choice in favor of Sapien valves to lower the risk of post-TPVI endocarditis may be beneficial.

Outcomes of Transannular Repair of Tetralogy of Fallot With a Contegra® Monocuspid Patch

BACKGROUND

Surgical repair of tetralogy of Fallot (ToF) depends on the anatomical variations of the heart defect. A group of patients with a hypoplastic pulmonary valve annulus required a transannular patch. This study aimed to evaluate the early and late outcomes of ToF repair with a transannular Contegra® monocuspid patch in a single center.

METHODS

A retrospective review of medical records was conducted. This study included 224 children with a median age of 13 months who underwent ToF repair with a Contegra® transannular patch in over 20 years of observation. The primary outcomes were hospital mortality and need for early reoperations. The secondary outcomes were late death and event-free survival.

RESULTS

The hospital mortality in our group was 3.1%, whereas two patients required early reoperation. Three patients were excluded from the study because follow-up data were not available. In the remaining group of patients (212 patients), the median follow-up was 116 (range, 1-206) months. One patient died because of sudden cardiac arrest at home six months after surgery. Event-free survival was observed in 181 patients (85.4%), whereas the remaining 30 patients (14.1%) required graft replacement. The median time to reoperation was 99 (range, 4-183) months.

CONCLUSIONS

Although surgical treatment of ToF has been performed for more than 60 years worldwide, the optimal approach in children with a hypoplastic pulmonary valve annulus remains debatable. Among options, the Contegra® monocuspid patch can be effectively used in transannular repair of ToF with good long-term results.

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

BACKGROUND

Conduit 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.

METHODS

A 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.

RESULTS

A 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).

CONCLUSIONS

RVOT 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.

Long-Term Follow-Up of Right Ventricle to Pulmonary Artery Biologic Valved Conduits Used in Pediatric Congenital Heart Surgery

Valved conduit reconstruction between the right ventricle (RV) and the pulmonary circulation is often necessary in the surgical treatment of complex congenital heart defects. The aim of this study is to evaluate the long-term performance of the three types of conduits we have used and assess risk factors for conduit failure. Retrospective, single-center review of 455 consecutive pediatric patients with 625 conduits from 1990 to 2019 undergoing RV-to-pulmonary artery (PA) reconstruction with a valved conduit. The three conduit types investigated were pulmonary homograft, aorta homograft, and bovine jugular vein (BJV) graft. Overall patient survival was 91.4%, freedom from conduit replacement (FCR) was 47.4%, and freedom from reintervention (FFR) was 37.8% with a median follow-up of 8.7 years (interquartile range 4.3-13.3 years). For pulmonary homografts, 10-, 20-, and 28-year FCR was 79.6%, 68.6%, and 66.0%, respectively. For aortic homografts, 10-, 20-, and 30-year FCR was 49.8%, 31.5%, and 23.0%, respectively. For BJV grafts, 10- and 19-year FCR was 68.1% and 46.0%, respectively. When controlling for baseline variables, FCR was similar for pulmonary homografts and BJV grafts. Overall patient survival was excellent. Risk factors for conduit failure in patients operated with reconstruction of the RV-PA outflow tract included low age, low weight, small conduit size, and certain cardiac diagnoses. There was no evidence for a shorter life span of the second graft. Pulmonary homografts and BJV grafts performed similarly but the risk of endocarditis was greater in the BJV group.

A rare case of mycotic pseudoaneurysm in a patient post Rastelli procedure with infective endocarditis

Mycotic pseudoaneurysm secondary to infective endocarditis is an uncommon complication in CHD with conduit placement. We report a case of late presentation of bacterial infective endocarditis with pseudoaneurysm in an 8-year-old girl with underlying pulmonary atresia with ventricular septal defect, post Rastelli procedure done at the age of 3 years old.

Outcomes after right ventricular outflow tract reconstruction with valve substitutes: A systematic review and meta-analysis

Introduction

This study aims to provide an overview of outcomes after right ventricular outflow tract (RVOT) reconstruction using different valve substitutes in different age groups for different indications.

Methods

The literature was systematically searched for articles published between January 2000 and June 2021 reporting on clinical and/or echocardiographic outcomes after RVOT reconstruction with valve substitutes. A random-effects meta-analysis was conducted for outcomes, and time-related outcomes were visualized by pooled Kaplan–Meier curves. Subgroup analyses were performed according to etiology, implanted valve substitute and patient age.

Results

Two hundred and seventeen articles were included, comprising 37,078 patients (age: 22.86 ± 11.29 years; 31.6% female) and 240,581 patient-years of follow-up. Aortic valve disease (Ross procedure, 46.6%) and Tetralogy of Fallot (TOF, 27.0%) were the two main underlying etiologies. Homograft and xenograft accounted for 83.7 and 32.6% of the overall valve substitutes, respectively. The early mortality, late mortality, reintervention and endocarditis rates were 3.36% (2.91–3.88), 0.72%/y (95% CI: 0.62–0.82), 2.62%/y (95% CI: 2.28–3.00), and 0.38%/y (95%CI: 0.31–0.47) for all patients. The early mortality for TOF and truncus arteriosus (TA) were 1.95% (1.31–2.90) and 10.67% (7.79–14.61). Pooled late mortality and reintervention rate were 0.59%/y (0.39–0.89), 1.41%/y (0.87–2.27), and 1.20%/y (0.74–1.94), 10.15%/y (7.42–13.90) for TOF and TA, respectively. Endocarditis rate was 0.21%/y (95% CI: 0.16–0.27) for a homograft substitute and 0.80%/y (95%CI: 0.60–1.09) for a xenograft substitute. Reintervention rate for infants, children and adults was 8.80%/y (95% CI: 6.49–11.95), 4.75%/y (95% CI: 3.67–6.14), and 0.72%/y (95% CI: 0.36–1.42), respectively.

Conclusion

This study shows RVOT reconstruction with valve substitutes can be performed with acceptable mortality and morbidity rates for most patients. Reinterventions after RVOT reconstruction with valve substitutes are inevitable for most patients in their life-time, emphasizing the necessity of life-long follow-up and multidisciplinary care. Follow-up protocols should be tailored to individual patients because patients with different etiologies, ages, and implanted valve substitutes have different rates of mortality and morbidity.

Systematic review registration

[www.crd.york.ac.uk/prospero], identifier [CRD42021271622].

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.

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.

Nationwide Registry-Based Analysis of Infective Endocarditis Risk After Pulmonary Valve Replacement

Background Infective endocarditis (IE) after pulmonary valve replacements in congenital heart disease is a significant concern. This study aimed to identify specific long-term risk factors for IE after percutaneous pulmonary valve implantation or surgical pulmonary valve replacement. Methods and Results All patients with congenital heart disease from the National Register for Congenital Heart Defects with at least 1 pulmonary valve replacement before January 2018 were included. A total of 1170 patients (56.3% men, median age at study inclusion 12 [interquartile range {Q1-Q3} 5-20 years]) received 1598 pulmonary valve replacements. IE occurred in 4.8% of patients during a follow-up of total 9397 patient-years (median 10 [Q1-Q3, 6-10] years per patient). After homograft implantation 7 of 558 (1.3%) patients developed IE, after heterograft implantation 31 of 723 (4.3%) patients, and after Melody valve implantation 18 of 241 (7.5%) patients. Edwards Sapien and mechanical valves were used less frequently and remained without IE. The incidence of IE in heterografts excluding Contegra valves was 7 of 278 (2.5%), whereas the incidence of IE in Contegra valves was 24 of 445 (5.4%). The risk of IE was not increased compared with homografts if Contegra valves were excluded from the heterografts (hazard ratio [HR], 2.60; P=0.075). The risk of IE was increased for bovine jugular vein valves, Contegra valves (HR, 6.72; P<0.001), and Melody valves (HR, 5.49; P<0.001), but did not differ between Melody valves and Contegra valves (HR, 1.01; P=0.978). Conclusions Bovine jugular vein valves have the highest risk of IE, irrespective of the mode of deployment, either surgical or percutaneous.

Selective Valve Removal for Melody Valve Endocarditis: Practice Variations in a Multicenter Experience

Guidelines for management of Melody transcatheter pulmonary valve (TPV) infective endocarditis (IE) are lacking. We aimed to identify factors associated with surgical valve removal versus antimicrobial therapy in Melody TPV IE. Multicenter retrospective analysis of all patients receiving Melody TPV from 10/2010 to 3/2019 was performed to identify cases of IE. Surgical explants versus non-surgical cases were compared. Of the 663 Melody TPV implants, there were 66 cases of IE in 59 patients (59/663, 8.8%). 39/66 (59%) were treated with IV antimicrobials and 27/66(41%) underwent valve explantation. 26/59 patients (44%) were treated medically without explantation or recurrence with average follow-up time of 3.5 years (range:1-9). 32% of Streptococcus cases, 53% of MSSA, and all MRSA cases were explanted. 2 of the 4 deaths had MSSA. CART analysis demonstrated two important parameters associated with explantation: a peak echo gradient ≥ 47 mmHg at IE diagnosis(OR 10.6, p < 0.001) and a peak echo gradient increase of > 24 mmHg compared to baseline (OR 6.7, p = 0.01). Rates of explantation varied by institution (27 to 64%). In our multicenter experience, 44% of patients with Melody IE were successfully medically treated without valve explantation or recurrence. The degree of valve stenosis at time of IE diagnosis was strongly associated with explantation. Rates of explantation varied significantly among the institutions.

Comparison of homografts and bovine jugular vein conduits in the pulmonary position in patients <20 years of age

OBJECTIVE

To compare the performance of homografts and bovine jugular vein (BJV) conduits in the pulmonary position.

METHODS

All 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.

RESULTS

The 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.

CONCLUSIONS

In 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.

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.

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.

Diagnostic Value of 18F-Fluorodeoxyglucose Positron Emission Tomography Computed Tomography in Prosthetic Pulmonary Valve Infective Endocarditis

OBJECTIVES

The aim of this study was to assess the diagnostic performances of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) in congenital heart disease (CHD) patients with pulmonary prosthetic valve or conduit endocarditis (PPVE) suspicion.

BACKGROUND

PPVE is a major issue in the growing CHD population. Diagnosis is challenging, and usual imaging tools are not always efficient or validated in this specific population. Particularly, the diagnostic yield of ¹⁸F-FDG PET/CT remains poorly studied in PPVE.

METHODS

A retrospective multicenter study was conducted in 8 French tertiary centers. Children and adult CHD patients who underwent ¹⁸F-FDG PET/CT in the setting of PPVE suspicion between January 2010 and May 2020 were included. The cases were initially classified as definite, possible, or rejected PPVE regarding the modified Duke criteria and finally by the Endocarditis Team consensus. The result of ¹⁸F-FDG PET/CT had been compared with final diagnosis consensus used as gold-standard in our study.

RESULTS

A total of 66 cases of PPVE suspicion involving 59 patients (median age 23 years, 73% men) were included. Sensitivity, specificity, positive predictive value, and negative predictive value of ¹⁸F-FDG PET/CT in PPVE suspicion were respectively: 79.1% (95% CI: 68.4%-91.4%), 72.7% (95% CI: 60.4%-85.0%), 91.9% (95% CI: 79.6%-100.0%), and 47.1% (95% CI: 34.8%-59.4%). ¹⁸F-FDG PET/CT findings would help to correctly reclassify 57% (4 of 7) of possible PPVE to definite PPVE.

CONCLUSIONS

Using ¹⁸F-FDG PET/CT improves the diagnostic accuracy of the Duke criteria in CHD patients with suspected PPVE. Its high positive predictive value could be helpful in routine to shorten diagnosis and treatment delays and improve clinical outcomes.

Surgical therapy of infective endocarditis following interventional or surgical pulmonary valve replacement

OBJECTIVES

Percutaneous pulmonary valve prostheses and right ventricle-to-pulmonary artery conduits are at risk for infective endocarditis (IE). In children and adults with a congenital heart disease, a pulmonary valve implant is frequently necessary. Prosthetic valve endocarditis is a conservatively barely manageable, serious life-threatening condition. We investigated the results of surgical pulmonary valve replacements in patients with IE.

METHODS

A total of 20 patients with congenital heart disease with the definite diagnosis of IE between March 2013 and July 2020 were included in this single institutional, retrospective review. Infected conduits were 11 Melody, 5 Contegra, 3 homografts and 1 Matrix P Plus. All of the infected prosthetic material was removed from the right ventricular outflow tract up to the pulmonary bifurcation. Pulmonary homografts were implanted after pulmonary root resection as right ventricle-to-pulmonary artery conduits.

RESULTS

All patients survived and were discharged infection-free. The mean time from the conduit implant to the operation for IE was 4.9 years [95% confidence interval (CI), 3.0-6.9]. The median intensive care unit stay was 3.0 days (95% CI, 2.0-4.7), and the median hospital time was 25.0 days (95% CI, 19.2-42.0). Median follow-up time was 204.5 days (range 30 days to 5 years) without death or recurrent endocarditis.

CONCLUSIONS

The surgical treatment of IE of percutaneous pulmonary valve prostheses and right ventricle-to-pulmonary artery conduits is a safe and effective therapeutic concept. Early surgical referral of patients with suspicion of IE should be pursued to avoid sequelae such as right ventricular failure, septic emboli, intracardiac expansion and antibiotic resistance.

Time-related risk of pulmonary conduit re-replacement: a Congenital Heart Surgeons' Society Study

BACKGROUND

Patients receiving a right ventricle-to-pulmonary artery conduit in infancy will require successive procedures or replacements, each with variable longevity. We sought to identify factors associated with time-related risk of a subsequent surgical replacement (PC3) or transcatheter pulmonary valve insertion (TPVI) after a second surgically-placed PC (PC2).

METHODS

From 2002 to 2016, 630 patients from 29 Congenital Heart Surgeons' Society member institutions survived to discharge after initial valved PC insertion (PC1) at age < 2 years. Of those, 355 had undergone surgical replacement (PC2) of that initial conduit. Competing risk methodology and multiphase parametric hazard analyses were used to identify factors associated with time-related risk of PC3 or TPVI.

RESULTS

Of 355 PC2 patients (median follow-up of 5.3 years), 65 underwent PC3 and 41 TPVI. Factors at PC2 associated with increased time-related risk of PC3 were smaller PC2 Z score (Hazard Ratio [HR] 1.6, p<0.001), concomitant aortic valve intervention (HR 7.6, p=0.009), aortic allograft (HR 2.2, p=0.008), younger age (HR 1.4, p<0.001), and larger Z score of PC1 (HR 1.2, p=0.04). Factors at PC2 associated with increased time-related risk of TPVI were aortic allograft (HR: 3.3, p=0.006), porcine unstented conduit (HR 4.7, p<0.001), and older age (HR 2.3, p=0.01).

CONCLUSIONS

Aortic allograft as PC2 was associated with increased time-related risk of both PC3 and TPVI. Surgeons may reduce risk of these subsequent procedures by not selecting an aortic homograft at PC2, and by oversizing the conduit when anatomically feasible.

High incidence of fever in patients after biointegral pulmonic valved conduit implantation

OBJECTIVE

To describe our short- and medium-term outcomes using the BioIntegral pulmonic conduit.

METHODS

Between August 2018 and September 2019, the BioIntegral pulmonic valved conduit was used for right ventricular outflow tract reconstruction in 48 patients. The data were retrospectively retrieved from the patient charts.

RESULTS

The median age at surgery was 36 months (interquartile range [IQR] = 18-62 months). The diagnoses were pulmonary atresia-ventricular septal defect in 28 patients, absent pulmonary valve in four patients, truncus arteriosus in six patients, TGA-VSD-PS in five patients, conduit stenosis in three patients, and left venticular outflow tract obstruction requiring a Ross operation in two patients. In the postoperative short-term follow-up, 15 patients out of 48 had a high fever. Of these, 12 patients had concomitantly elevated C-reactive protein levels. There were no patients with blood culture positivity. The median postoperative length of hospital stay was 14 days (IQR = 8-21 days). The overall mortality was 4% in two patients, one died of right ventricular failure and multiple organ failure and one died of pulmonary embolism. The two patients who died were not among the 15 patients with fever. However, four patients with fever underwent balloon angioplasty for conduit restenosis in their medium-term follow-up.

CONCLUSION

There was a high incidence of fever and adverse outcomes in the short-term postoperative follow-up of patients in whom the BioIntegral pulmonic valved conduit was implanted. Caution is advisable in using these conduits until there is convincing evidence about the sterilization and storage standards of these grafts.

Outcomes Following Heterotopic Placement of Right Ventricle to Pulmonary Artery Conduits

BACKGROUND

We sought to evaluate the outcomes following right ventricle to pulmonary artery (RV-PA) conduit placement in pediatric patients, excluding those with a RV-PA conduit for the Ross procedure which is associated with improved conduit durability, partly related to its orthotopic position.

METHODS

Outcomes for 119 patients who underwent RV-PA conduit placement at a single institution from January 2004 to December 2016 were reviewed. Primary outcome measures were reintervention-free survival (RFS) and overall survival. Survival analyses were performed using the Kaplan-Meier method, and risk factors associated with reintervention were evaluated.

RESULTS

The median age at the time of conduit placement was 6 months (interquartile range, IQR: 1-14), and the median length of follow-up was 63 months (range: 0-156). During follow-up, 39 patients required conduit-related reintervention, while 6 patients died perioperatively with an overall survival of 90% at 10 years. Among the remaining 113 patients, the RFS at one, five, and ten years was 91% (84%-95%), 72% (60%-80%), and 33% (16%-50%), respectively. The median time to conduit replacement in the series was 43.5 months (IQR: 19.3-76.2). The use of a pulmonary homograft was associated with improved RFS (P = .03), and this was particularly pronounced in comparison with aortic homografts in neonates. Infection was the indication for replacement in only one patient.

CONCLUSIONS

The majority of the conduits placed during the neonatal period required conduit replacement before the age of five years. Endocarditis was not a common indication for replacement. In neonates and infants, we prefer pulmonary homografts for most indications.

Placement of Labcor Pulmonary Conduit Results in a High Incidence of Postoperative Fever

BACKGROUND

Fever in the postoperative period in cardiac patients is common. The purpose of this study is to recognize the risk factors for prolonged postoperative fever in cardiac patients with pulmonary conduit insertion.

METHODS

Patients were identified retrospectively by looking at the International Classification of Diseases, Ninth Revision, Clinical Modification procedure code for pulmonary conduit insertion between June 2009 and December 2015 at the American University of Beirut Medical Center. Data about preoperative, perioperative, and postoperative variables were collected. Data entry and analysis were performed using SPSS version 22.

RESULTS

The study identified 59 patients. The most common type of pulmonary conduit used was the Contegra type (57.6%) (n = 34), followed by the Labcor type (20.3%; n = 12). Postoperative fever occurred in 61% of patients (n = 36). Fourteen patients (38.8%) had a prolonged fever that lasted for more than seven days. Prolonged postoperative fever was significantly associated with the Labcor pulmonary conduit (P value < .001) and a longer duration of pacing wires (P value: .039). Significantly prolonged fever that lasted for more than 21 days occurred in five patients who all had inserted the Labcor pulmonary conduit.

CONCLUSIONS

The Labcor pulmonary conduit type is a risk factor for prolonged postoperative fever. The protracted use of pacing wires could be a consequence of the prolonged fever rather than a cause. In the absence of a demonstrable infectious etiology for prolonged postoperative fever in cardiac patients with pulmonary conduit insertion, the Labcor pulmonary conduit could be the underlying cause. Alternative management of such cases may lead to decreased antibiotic use and morbidity.

Expanded Polytetrafluoroethylene Conduits With Bulging Sinuses and a Fan-Shaped Valve in Right Ventricular Outflow Tract Reconstruction

We developed a handmade expanded polytetrafluoroethylene (ePTFE) pulmonary valvular conduit (PVC) with bulging sinuses and a fan-shaped ePTFE valve for right ventricular outflow tract (RVOT) reconstruction. We aimed to investigate the results of this device in this multicenter study. From 2001 to 2020, 1776 patients underwent RVOT reconstruction using ePTFE PVCs at 65 institutions in Japan. The median age and body weight were 4.1 years (range, 3 days to 67.1 years) and 13.3 (range, 1.8-91.3) kg, respectively. The median PVC size was 18 (range, 8-24) mm. The median Z-value of the ePTFE PVC was 1.1 (range, -3.8 to 5.0). The ePTFE PVC conditions were investigated by cardiac echocardiography and catheterization. The median follow-up period was 3.3 years (range, 0 day to 16.2 years). There were only 9 cases (0.5%) with PVC-related unknown deaths. Reintervention was performed in 283 patients (15.9%), and 190 patients (10.7%) required explantation. Freedom from reintervention and explantation at 5/10 years were 86.7/61.5% and 93.0/69.1%, respectively. At the latest echocardiography, PVC regurgitation grade was better than mild in 88.4% patients. The average peak RVOT gradient was 15.7 ± 15.9 mm Hg at the latest cardiac catheterization. ePTFE PVC infection was detected in only 8 patients (0.5%). Relative stenosis due to somatic growth was the most common cause of PVC explantation. The performance of ePTFE in terms of durability, valvular performance, and the resistance against infection is considerable and may replace conventional prosthetic materials. Further improvement of the ePTFE membrane is essential to prevent valvular dysfunction.

Outcomes of Right Ventricular Outflow Tract Reconstruction in Children: Retrospective Comparison Between Bovine Jugular Vein and Expanded Polytetrafluoroethylene Conduits

Bovine jugular vein (BJV) and expanded polytetrafluoroethylene (ePTFE) conduits have been described as alternatives to the homograft for right ventricular outflow tract (RVOT) reconstruction. This study compared RVOT reconstructions using BJV and ePTFE conduits performed in a single institution. The valve functions and outcomes of patients aged < 18 years who underwent primary RVOT reconstruction with a BJV or ePTFE conduit between 2013 and 2017 were retrospectively investigated. 44 patients (20 and 24 with BJV and ePTFE conduits, respectively) met the inclusion criteria. The mean follow-up time was 4.5 ± 1.5 years. No significant differences in peak RVOT velocity (1.8 ± 0.9 m/s vs 2.1 ± 0.9 m/s, P = 0.27), branch pulmonary stenosis (P = 0.50), or pulmonary regurgitation (P = 0.44) were found between the BJV and ePTFE conduit groups, respectively. Aneurysmal dilatation of the conduit was observed in 25.0% of the patients in the BJV conduit group but not in the ePTFE conduit group (P = 0.011). All the cases with aneurysmal dilatation of the BJV conduit were complicated with branch pulmonary stenosis up to 3.0 m/s (P = 0.004). No conduit infections occurred during the follow-up period, and no significant difference in conduit replacement (20.0% vs 8.3%, P = 0.43) was found between the BJV and ePTFE conduit groups, respectively. The outcomes of the RVOT reconstructions with BJV and ePTFE conduits were clinically satisfactory. Aneurysmal dilatation was found in the BJV conduit cases, with branch pulmonary stenosis as the risk factor.

Staphylococcus aureus adheres avidly to decellularised cardiac homograft tissue in vitro in the fibrinogen-dependent manner

OBJECTIVE

Infective endocarditis remains a severe complication associated with a high morbidity and mortality in patients after heart valve replacement. Exploration of the pathogenesis is of high demand and we, therefore, present a competent model that allows studying bacterial adherence and the role of plasma fibrinogen in this process using a new in-house designed low-volume flow chamber. Three cardiac graft tissues used for pulmonary valve replacement have been tested under shear conditions to investigate the impact of surface composition on the adhesion events.

METHODS

Tissue pieces of cryopreserved homograft (non-decellularised), decellularised homograft and bovine pericardium patch were investigated for fibrinogen binding. Adherence of Staphylococcus aureus to these graft tissues was studied quantitatively under flow conditions in our newly fabricated chamber based on a parallel plates' modality. The method of counting colony-forming units was reliable and reproducible to assess the propensity of different graft materials for bacterial attachment under shear.

RESULTS

Bacterial perfusions over all plasma-precoated tissues identified cryopreserved homograft with the lowest affinity for S. aureus compared to decellularised homograft presenting a significantly higher bacterial adhesion (p < 0.05), which was linked to a more avid fibrinogen binding (p < 0.01). Bovine pericardial patch, as a reference tissue in this study, was confirmed to be the most susceptible tissue graft for the bacterial adhesion, which was in line with our previous work.

CONCLUSION

The two studied homograft tissues showed different levels of bacterial attachment, which might be postulated by the involvement of fibrinogen in the adhesion mechanism(s) shown previously for bovine tissues.

Long-term clinical outcome and echocardiographic function of homografts in the right ventricular outflow tract†

OBJECTIVES

Although homografts are often the preferred valve conduits for right ventricular outflow tract (RVOT) reconstruction, data on long-term homograft-related outcomes, durability and impact on quality of life (QoL) are scarce. The aim of this study was therefore to describe the long-term homograft function, clinical outcomes and QoL after RVOT reconstruction.

METHODS

We performed a single-centre retrospective analysis of all consecutive patients who underwent RVOT reconstruction with a homograft. Multiple subsequent allografts in the same patients were regarded as separate subjects. Valve-related events were analysed by Kaplan-Meier and Life Table methods. Serial echocardiographic measurements were analysed with mixed effects models. In addition, QoL was repeatedly assessed and compared with a matched general population.

RESULTS

In total, 701 consecutive homografts were implanted in 604 patients [59.6% males, mean age at operation 19.5 ± 15.2 (standard deviation)]. Hospital mortality was 3.3%. After 25 years follow-up, survival and freedom from valve replacement were 84 ± 4% and 56 ± 6%, respectively. Freedom from valve replacement after 15 years for patients under 1 year of age was 28 ± 14% years, for those between 1 and 18 years, 59 ± 8%, and for those older than 18 years, 82 ± 5%. The peak gradient increased predominantly in the first postoperative decade in infants and paediatric patients from 19 to 54 mmHg. In adults, the average gradient increased from 9 to 31 mmHg after 14 years. Compared to a gender- and age-matched Dutch population, patients reported lower vitality and general health but less bodily pain. Patients, in whom QoL was repeatedly assessed, reported lower scores on physical functioning and vitality after a 5-year follow-up period. However, we found no differences in any of the subscales in patients who underwent valve replacement during the 5-year interval.

CONCLUSIONS

Homografts are a durable valve alternative for RVOT reconstruction; in particular, adults show extensive freedom from valve replacement and report QoL comparable with healthy subjects. An online interactive application form created by our institution can be used to assess patient outcome after RVOT reconstruction with a homograft for different patient profiles.

Surgery for Truncus Arteriosus: Contemporary Practice

Surgery for truncus arteriosus has an early mortality of 3% to 20%, with a long-term survival of approximately 75% at 20 years. Nowadays, truncus arteriosus repair is mostly done in the neonatal period together with a single-staged repair of concomitant cardiovascular anomalies. There are many challenging subgroups of patients with truncus arteriosus, including those with clinically significant truncal valve insufficiency, an interrupted aortic arch, or a coronary artery anomaly. In fact, truncal valve competency appears to be the most important factor influencing the outcomes after truncus arteriosus repair. The use of a conduit during truncus arteriosus repair invariably requires reoperation on the right ventricular outflow tract. Through improvements in perioperative techniques over time, many children are now living well into adulthood after repair of truncus arteriosus, albeit with a high rate of reoperation. Despite this, the long-term outcomes of truncus arteriosus repair are good, with many patients being asymptomatic and with a quality of life comparable to the general population.

Experience and Outcomes of Surgically Implanted Melody Valve in the Pulmonary Position

BACKGROUND

Multiple congenital cardiac malformations require pulmonary valve replacement and/or right ventricular outflow (RVOT) reconstruction. Pulmonary valve replacement remains challenging in children owing to the limited growth potential of prosthetic valves. We evaluated outcomes in patients undergoing surgical implantation of a Melody valve in the RVOT.

METHODS

Data were retrospectively collected for 23 patients undergoing surgical Melody valve implantation at Boston Children's Hospital between 2009 and 2019. We assessed postoperative valve function, reintervention rates, and mortality.

RESULTS

Median age was 1.7 years (range, 2 months to 6 years); 12 patients were aged greater than 2 years (52%). Diagnosis was tetralogy of Fallot in 15 patients (65%); 15 had a prior RVOT operation (65%). The Melody valve was dilated before surgery to a median diameter of 14 mm (range, 10-20 mm). No patients had acute pulmonary regurgitation. One required transcatheter RVOT reintervention before discharge. Median follow-up was 3.7 years (range, 0.02-8.7 years) with moderate or greater pulmonary regurgitation in 2 patients. Catheter-based interventions (mean, 0.83 ± 1.07/patient) occurred at a median of 1 year (range, 16 days to 5.4 years) and included valve expansion for somatic growth (n = 10) and subsequent valve-in-valve replacement (n = 3). Three patients (13%) required surgical valve explant or replacement at a median of 1.0 year (range, 0.6-3.7 years) for Melody-specific indications. One-, 3-, and 5-year freedom from Melody-driven reoperation was 90%, 90%, and 83%, respectively.

CONCLUSIONS

The Melody valve can be surgically implanted in the RVOT of young patients with acceptable early results. These valves can be successfully dilated through transcatheter reintervention to accommodate growth.

Durability of the St. Jude Epic Supra Bioprosthetic Valve in the Pulmonary Position

Epic Supra valves have been used off-label in the pulmonary position. We aim to evaluate the durability of Epic valves in the pulmonary position. We performed a retrospective review of all Epic valves placed in the pulmonary position from October 2008 to May 2019. Time-to-event analysis was performed using Kaplan-Meier estimates to evaluate freedom from valve intervention, moderate pulmonary regurgitation, and peak velocity greater than 3.5 m/s. Valve dysfunction was a composite of all 3 end points. A total of 79 patients had Epic valves implanted in the pulmonary position. Median age was 18.5 years (15th-85th percentile 11.2-41.0). In total, 1 (1%) 19 mm valve, 4 (5%) 21 mm valves, 8 (10%) 23 mm valves, 23 (29%) 25 mm valves, and 43 (54%) 27 mm valves were implanted. There were no deaths or transplants. Median follow-up was 3.1 years (interquartile range 1.0-5.5). At 5 years, freedom from valve intervention was 95%, freedom from valve dysfunction was 68%, freedom from moderate pulmonary regurgitation was 73%, and freedom from peak velocity greater than 3.5 m/s was 82%. Epic Supra valves provide an acceptable valve replacement in the pulmonary position for children and adults. Longer follow-up is needed to determine valve durability through the entirety of the valve life expectancy.

Transcatheter Versus Surgical Pulmonary Valve Replacement: A Systemic Review and Meta-Analysis

BACKGROUND

Transcatheter pulmonary valve replacement (TPVR) has emerged as an alternative to surgery in patients with pulmonary valve dysfunction.

METHODS

We searched the Medline and Cochrane databases since their inception to January 2019 as well as references from article, for all publications comparing TPVR with surgical PVR (SPVR). Studies were considered for inclusion if they reported comparative data regarding any of the study endpoints. The primary endpoint was early mortality after PVR. Secondary endpoints included procedure-related complications, length of hospital stay, mortality during follow-up, infective endocarditis, need for reintervention, post-PVR transpulmonary peak systolic gradient, and significant pulmonary regurgitation.

RESULTS

There were no differences in perioperative mortality between groups (0.2% vs 1.2%; pooled odds ratio, 0.56; 95% confidence interval, 0.19-1.59; P = .27, I² = 0%). However TPVR conferred a significant reduction in procedure-related complications and length of hospital stay compared with SPVR. Midterm mortality and the need for repeat intervention were similar with both techniques, but pooled infective endocarditis was significantly more frequent in the TPVR group (5.8 vs 2.7%; pooled odds ratio, 3.09; 95% confidence interval, 1.89-5.06; P < .001, I² = 0%). TPVR was associated with less significant PR and a trend towards a lower transpulmonary systolic gradient during follow-up.

CONCLUSIONS

TPVR is a safe alternative to SPVR in selected patients and is associated with a shorter length of hospital stay and fewer procedure-related complications. At midterm follow-up TPVR was comparable with SPVR in terms of mortality and repeat intervention but was associated with an increased risk of infective endocarditis.

Bovine jugular vein conduit versus pulmonary homograft in the Ross operation

OBJECTIVES

The Ross procedure involves using the native pulmonary valve for aortic valve replacement then replacing the pulmonary valve with an allograft or xenograft. We aimed to compare our age-matched experience with the bovine jugular vein conduit and the pulmonary homograft for pulmonary valve replacement during the Ross procedure in children.

METHODS

Between 1998 and 2016, 15 patients <18 years of age underwent a Ross procedure using the bovine jugular vein conduit (Ross-Bovine Jugular Vein Conduit) at our institution. These patients were age-matched with 15 patients who had the Ross operation with a standard pulmonary homograft for right ventricular outflow tract reconstruction (Ross-Pulmonary Homograft). Paper and electronic medical records were retrospectively reviewed.

RESULTS

The median age of the Ross-Bovine Jugular Vein Conduit and Ross-Pulmonary Homograft patients were 4.8 years (interquartile range 1.1-6.6) and 3.3 years (interquartile 1.2-7.6), respectively (p = 0.6). The median follow-up time for the Ross-Bovine Jugular Vein Conduit and Ross-Pulmonary Homograft groups were 1.7 years (interquartile range 0.5-4.9) and 6.8 years (interquartile range 1.9-13.4), respectively (p = 0.03). Overall, 5-year survival, freedom from redo aortic valve replacement, and freedom from pulmonary valve replacement were similar between groups.

CONCLUSION

The bovine jugular vein conduit and pulmonary homograft have favourable mid-term durability when used for right ventricular outflow tract reconstruction for the Ross operation. The bovine jugular vein conduit may be a suitable replacement for appropriately sized patients undergoing a Ross aortic valve replacement, though longer follow-up is needed.