Aortic Valve Replacement and the Ross Operation in Children and Young Adults

Long-term outcome after the Ross procedure in 173 adults with up to 25 years of follow-up

OBJECTIVES

The potential risk of autograft dilatation and homograft stenosis after the Ross procedure mandates lifelong follow-up. This retrospective cohort study aimed to determine long-term outcome of the Ross procedure, investigating autograft and homograft failure patterns leading to reintervention.

METHODS

All adults who underwent the Ross procedure between 1991 and 2018 at the University Hospitals Leuven were included, with follow-up data collected retrospectively. Autograft implantation was performed using the full root replacement technique. The primary end-point was long-term survival. Secondary end-points were survival free from any reintervention, autograft or homograft reintervention-free survival, and evolution of autograft diameter, homograft gradient and aortic regurgitation grade over time.

RESULTS

A total of 173 adult patients (66% male) with a median age of 32 years (range 18-58 years) were included. External support at both the annulus and sinotubular junction was used in 38.7% (67/173). Median follow-up duration was 11.1 years (IQR, 6.4-15.9; 2065 patient-years) with 95% follow-up completeness. There was one (0.6%) perioperative death. Kaplan-Meier estimate for 15-year survival was 91.1% and Ross-related reintervention-free survival was 75.7% (autograft: 83.5%, homograft: 85%). Regression analyses demonstrated progressive neoaortic root dilatation (0.56 mm/year) and increase in homograft gradient (0.72 mmHg/year).

CONCLUSIONS

The Ross procedure has the potential to offer excellent long-term survival and reintervention-free survival. These long-term data further confirm that the Ross procedure is a suitable option in young adults with aortic valve disease which should be considered on an individual basis.

Lifetime Management of Adolescents and Young Adults with Congenital Aortic Valve Disease

In this invited expert review, we focus on evolving lifetime management strategies for adolescents and young adults with congenital aortic valve disease, acknowledging that these patients often require multiple interventions during their lifetime. Our goal is to preserve the native aortic valve when feasible. Leveraging advanced multimodality imaging, a detailed assessment of the aortic valve and root complex can be obtained, and a surgically approach tailored to an individual patient's anatomy and pathology can be used. In turn, aortic valve repair and reconstruction can be offered to a greater number of patients, either as a definitive strategy or as a component of a staged strategy to delay the need for aortic valve replacement until later in life when more options are available.

The Ross Procedure in Children and Infants: A Systematic Review With Pooled Analyses

Background

The Ross procedure is a surgical option for congenital aortic stenosis that involves replacing the diseased aortic valve with a pulmonary autograft. Little is known about outcomes in children, particularly those younger than 1 year.

Methods

A systematic review with pooled analyses was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Inferred individual patient data were extracted from life tables. The primary end points were early (≤30 days) and late (>30 days) mortality rates following the Ross procedure in children. Secondary end points were freedom from reintervention for the right ventricular outflow tract and pulmonary autograft. These end points were assessed in the overall population of children. Sensitivity analyses were performed in subgroups younger than 1 year of age (infants) and in noninfant children.

Results

A total of 25 studies on 2737 patients met inclusion criteria. The pooled early survival rate was 96.0% (95% confidence interval [CI]: 95.1%-96.8%) overall and 86.8% (95% CI: 82.1%-90.3%) among infants. Pooled overall 10-year survival, freedom from pulmonary autograft reintervention, and freedom from right ventricular outflow tract reintervention rates were 91.1%, 90.2%, and 79.7%, respectively. Corresponding pooled rates in infants were 79.3%, 87.1%, and 51.2%. Mortality was significantly higher among infants compared with noninfant children (hazard ratio: 3.38, 95% CI: 2.44-4.68; P < 0.001). In metaregression analyses, younger age was strongly associated with poorer survival and higher reintervention rates.

Conclusions

Modest survival and autograft reoperation rates were observed following the Ross procedure in children. Surgery in infancy was strongly associated with poorer survival and higher reintervention rates.

Ross procedure: valve function, clinical outcomes and predictors after 25 years' follow-up

OBJECTIVE

To describe long-term outcomes of the Ross procedure in a single center and retrospective series after 25 years follow-up.

METHODS

From 1997-2019 we included all consecutive patients who underwent Ross procedure at our center. Clinical and echocardiographic evaluations were performed at least yearly. Echocardiographic valvular impairment was defined as at least moderate autograft or homograft dysfunction. Reintervention outcomes included surgical and percutaneous approach.

RESULTS

151 Ross procedures were performed (mean age 28±12years, 21 %<16years, 70 %male). After 25 years follow-up (median 18 years, interquartile range 9-21, only 3 patients lost) 12 patients died (8 %); Autograft, homograft or any valve dysfunction were present in 38(26 %), 48(32 %) and 75(51 %), respectively; and reintervention in 22(15%), 17(11%) and 38(26 %) respectively. At 20 years of follow-up, probabilities of survival free from autograft, homograft or any valve dysfunction were 63 %, 60 % and 35 %; and from reintervention, 80 %, 85 % and 67 %, respectively. The learning curve period (first 12 cases) was independently associated to autograft dysfunction (HR 2.78, 95 %CI:1.18-6.53, p = 0.02) and reintervention (HR 3.76, 95 %CI: 1.46-9.70, p = 0.006). Larger native pulmonary diameter was also an independent predictor of autograft reintervention (HR 1.22, 95 %CI:1.03-1.45, p = 0.03). Homograft dysfunction was associated with younger age (HR 5.35, 95 %CI: 2.13-13.47, p<0.001) and homograft reintervention, with higher left ventricle ejection fraction (HR 1,10, 95 %CI:1.02-1.19, p<0.02).

CONCLUSIONS

In this 25 years' experience after the Ross procedure, global survival was high, although autograft and homograft dysfunction and reintervention rates were not negligible. Clinical and echocardiographic variables can identify patients with higher risk of events in follow up.

Influence of preoperative aortic regurgitation on long-term autograft durability and dilatation in children and adolescents undergoing the Ross procedure

OBJECTIVE

Primary aortic insufficiency (AI) is a risk factor for autograft reintervention in adults undergoing the Ross procedure. We sought to examine the influence of preoperative AI on autograft durability in children and adolescents.

METHODS

From 1993 to 2020, 125 consecutive patients between ages 1 and 18 underwent a Ross procedure. The autograft was implanted using a full-root technique in 123 (98.4%) and included in a polyethelene terephthalate graft in 2 (1.6%). Patients with aortic stenosis (aortic stenosis group) (n = 85) were retrospectively compared with those with AI or mixed disease (AI group) (n = 40). Median length of follow-up was 8.2 years (interquartile range, 3.3-15.4 years). The primary end point was the incidence of severe AI or autograft reintervention. Secondary end points included changes in autograft dimensions analyzed using mixed-effect models.

RESULTS

The incidence of severe AI or autograft reintervention was 39.0% ± 13.0% in the AI group and 8.8% ± 4.4% in the aortic stenosis group at 15 years (P = .02). Annulus z scores increased in both aortic stenosis and AI groups over time (P < .001). However, the annulus dilated at a faster rate in the AI group (absolute difference, 3.8 ± 2.0 vs 2.5 ± 1.7; P = .03). Sinus of Valsalva z scores increased in both groups as well (P < .001), but at similar rates over time (P = .11).

CONCLUSIONS

Children and adolescents with AI undergoing the Ross procedure have higher rates of autograft failure. Patients with preoperative AI have more pronounced dilatation at the annulus. Akin to adults, a surgical aortic annulus stabilization technique that modulates growth is needed in children.

The Ross Procedure: Imaging, Outcomes and Future Directions in Aortic Valve Replacement

The Ross procedure is gaining recognition as a significant option for aortic valve replacement (AVR), and is particularly beneficial in specific patient groups. Although categorized as a class IIb recommendation in the 2020 American College of Cardiology (ACC)/American Heart Association (AHA), and the European Society of Cardiology (ESC) management guidelines on valvular heart disease, recent studies bolster its credibility. Research, including a propensity-matched study, underlines the Ross procedure's association with enhanced long-term survival and reduced adverse valve-related events compared to other AVR types. This positions the Ross procedure as a primary option for AVR in young and middle-aged adults within specialized centers, and potentially the only choice for children and infants requiring AVR. This review meticulously examines the Ross procedure, covering historical perspectives, surgical techniques, imaging, and outcomes, including hemodynamic performance and quality of life, especially focusing on pediatric and young adult patients. It explores contemporary techniques and innovations like minimally invasive approaches and tissue engineering, underscoring ongoing research and future directions. A summarization of comparative studies and meta-analyses reiterates the Ross procedure's superior long-term outcomes, valve durability, and preservation of the left ventricular function, accentuating the crucial role of patient selection and risk stratification, and pinpointing areas for future research.

Long-Term Outcomes of Ross Procedure versus Mechanical Aortic Valve Replacement: Meta-Analysis of Reconstructed Time-To-Event Data

In the era of lifetime management of aortic valve disease, the Ross procedure emerged as an alternative to prosthetic heart valves for young adults; however, more long-term data are warranted. We performed a meta-analysis of reconstructed time-to-event data to compare long-term outcomes between the Ross procedure and mechanical aortic valve replacement (mAVR) in young adults. PubMed/MEDLINE, EMBASE and GoogleScholar were searched for studies comparing Ross procedure with mAVR that reported mortality/survival rates and/or reoperation rates accompanied by at least one Kaplan-Meier curve for any of the outcomes. Six observational studies (5 with propensity score matching) including 5024 patients (Ross: 1737; mAVR: 3287) met our inclusion criteria. Patients who underwent Ross had a significantly lower risk of mortality in the overall population (HR 0.38, 95%CI 0.30-0.49, P<0.001; median follow-up of 7.2 years) and in the propensity score matched cohorts (HR 0.55, 95%CI 0.42-0.73, P<0.001; median follow-up of 10.2 years); however, the incidence function for the cumulative risk of reoperation was higher for the Ross procedure (HR 1.91, 95%CI 1.36-2.70, P<0.001; median follow-up of 9.3 years). Data from observational studies suggest that the Ross procedure is associated with lower all-cause mortality compared with mAVR; however, there is a higher risk of reoperation. Besides serving as basis to inform patients about benefits and risks involved in this choice, these results call for further randomized clinical trials to determine whether the Ross procedure can achieve its potential benefits in young patients in need of AVR.

Considering alternatives to transcatheter heart valves for managing patients with severe aortic valve stenosis

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) is becoming the standard of care for severe symptomatic aortic stenosis (AS). Yet, some patients with AS are not indicated/eligible for TAVI. Several noninvasive, catheter-based or surgical alternatives exist, and other therapeutic options are emerging.

AREAS COVERED

This review provides an overview of non-TAVI options for severe AS. Non-invasive, transcatheter, and alternative surgical strategies are discussed, emphasizing their backgrounds, techniques, and outcomes.

EXPERT OPINION

Alternative therapies to TAVI, whether device-based or non-device-based, continue to evolve or emerge and provide either alternative treatments or a bridge to TAVI, for patients not meeting indications for, or having contraindications to TAVI.Although TAVI and SAVR are the current dominant therapies, there are still some patients that could benefit in the future from other alternatives.Data on alternative options for such patients are scarce. Many advantages and disadvantages arise when selecting a specific treatment strategy for individual patients.Head-to-head comparison studies could guide physicians toward better patient selection and procedural planning. Awareness of therapeutic options, indications, techniques, and outcomes should enable heart teams to achieve optimized patient selection. Furthermore, it can increase the use of these alternatives to optimize the management of AS among different patient populations.

Long-Term Outcomes of Mechanical Aortic Valve Replacement in Children

When the options of aortic valve repair or the Ross procedure are not feasible or have been exhausted, mechanical aortic valve replacement (AVR) may provide a reliable and structurally durable alternative, but with the limitations of long-term anticoagulation, thrombosis risk and lack of valve growth potential. In this article, we review the longitudinal outcomes of mechanical AVR in children in our institution and compare them to those recently reported by others. From 1978 to 2020, 62 patients underwent mechanical AVR at a median age of 12.4 years (interquartile range (IQR): 8.6-16.8 years). The most common underlying diagnoses were: conotruncal anomalies (40%, 25/62), congenital aortic stenosis (16%, 10/62), rheumatic valve disease (16%, 10/62), connective tissue disease (8.1%, 5/62) and infective endocarditis (6.5%, 4/62). Thirty-two patients (52%, 32/62) had at least 1 prior aortic valve surgery prior to mechanical AVR. Early death was 3.2% (2/62). Median follow-up was 14.4 years (IQR: 8.4-28.2 years). Kaplan-Meier survival was 96.8%, 91.9%, 86.3%, and 81.9% at 1, 5, 10, and 20 years. On competing risk analysis, the proportion of patients alive without aortic valve reoperation at 1, 5, 10, and 20 years was 95.2%, 87.0%, 75.5% and 55.4%, respectively, while the proportion of patients that had aortic valve reoperation (with death as a competing event) at 1, 5, 10, and 20 years was 1.6%, 4.9%, 12.8%, and 28.5%, respectively. In conclusion, when the options of aortic valve repair or the Ross procedure are not feasible in children, mechanical AVR is an alternative, yet the long-term rates of mortality and need for aortic valve reoperation are of concern.

Outcomes after Mechanical Aortic Valve Replacement in Children with Congenital Heart Disease

Background

The optimal choice of valve substitute for aortic valve replacement (AVR) in pediatric patients remains a matter of debate. This study investigated the outcomes following AVR using mechanical prostheses in children.

Methods

Forty-four patients younger than 15 years who underwent mechanical AVR from March 1990 through March 2023 were included. The outcomes of interest were death or transplantation, hemorrhagic or thromboembolic events, and reoperation after mechanical AVR. Adverse events included any death, transplant, aortic valve reoperation, and major thromboembolic or hemorrhagic event.

Results

The median age and weight at AVR were 139 months and 32 kg, respectively. The median follow-up duration was 56 months. The most commonly used valve size was 21 mm (14 [31.8%]). There were 2 in-hospital deaths, 1 in-hospital transplant, and 1 late death. The overall survival rates at 1 and 10 years post-AVR were 92.9% and 90.0%, respectively. Aortic valve reoperation was required in 4 patients at a median of 70 months post-AVR. No major hemorrhagic or thromboembolic events occurred. The 5- and 10-year adverse event-free survival rates were 81.8% and 72.2%, respectively. In univariable analysis, younger age, longer cardiopulmonary bypass time, and smaller valve size were associated with adverse events. The cut-off values for age and prosthetic valve size to minimize the risk of adverse events were 71 months and 20 mm, respectively.

Conclusion

Mechanical AVR could be performed safely in children. Younger age, longer cardiopulmonary bypass time and smaller valve size were associated with adverse events. Thromboembolic or hemorrhagic complications might rarely occur.

Aortic valve repair versus the Ross procedure in children

BACKGROUND

Aortic valve repair and the Ross procedure are widely used in children; however, it is unclear which provides the best outcomes.

METHODS

Patients who underwent primary aortic valve surgery from 1980 to 2018 were included. Propensity score matching was performed to adjust for baseline differences.

RESULTS

Of 415 children, 82.7% (343/415) underwent repair and 17.3% (72/415) underwent the Ross procedure. At 15 years, survival was higher for aortic valve repair (93.9% ± 1.8% vs 80.9% ± 6.4%, P = .04); freedom from reoperation (45.7% ± 4.9% vs 48.5% ± 9.0%, P = .29) did not differ, and freedom from aortic valve reoperation was higher in the Ross procedure group (45.7% ± 4.9% vs 70.7% ± 8.0%, P < .001). When analyzed by quality of repair, acceptable repair provided the highest survival (P = .01). Acceptable repair and the Ross procedure had similar freedom from reoperation at 15 years, whereas suboptimal repair performed worse (acceptable: 54.9% ± 6.7%; Ross procedure: 48.5% ± 9.0%; suboptimal: 27.0% ± 7.7%, P < .001). Acceptable repair and the Ross procedure had similar freedom from aortic valve reoperation at 15 years, whereas suboptimal repair showed worse results (acceptable: 54.9 ± 6.7; Ross procedure: 70.7% ± 8.0%; suboptimal: 27.0% ± 7.7%, P < .001). Propensity score matching paired 66 patients who underwent the Ross procedure with 198 patients who underwent repair. At 15 years, repair was associated with better survival (98.0% ± 1.2% vs 78.5% ± 7.2%, P = .03), whereas freedom from reoperation was similar (42.6% ± 7.6% vs 50.7% ± 9.8%, P = .50). However, the Ross procedure was associated with higher freedom from aortic valve reoperation (42.6% ± 7.6% vs 72.3% ± 8.5%, P = .002).

CONCLUSIONS

Primary aortic valve repair was associated with better survival than the Ross procedure, whereas overall freedom from reoperation was similar. When an acceptable intraoperative result was achieved, outcomes of repair were favorable. However, when the intraoperative result of repair was suboptimal, the Ross procedure showed better results.

Repair of Aortic Regurgitation in Young Adults: Sooner Rather Than Later

Background Establishing surgical criteria for aortic valve replacement (AVR) in severe aortic regurgitation in young adults is challenging due to the lack of evidence-based recommendations. We studied indications for AVR in young adults with severe aortic regurgitation and their outcomes, as well as the relationship between presurgical echocardiographic parameters and postoperative left ventricular (LV) size, function, clinical events, and valve-related complications. Methods and Results Data were collected retrospectively on 172 consecutive adult patients who underwent AVR or repair for severe aortic regurgitation between 2005 and 2019 in a tertiary cardiac center (age at surgery 29 [22-41] years, 81% male). One-third underwent surgery before meeting guideline indications. Postsurgery, 65% achieved LV size and function normalization. LV ejection fraction showed no significant change from baseline. A higher presurgical LV end-systolic diameter correlated with a lack of LV normalization (odds ratio per 1-cm increase 2.81, P<0.01). The baseline LV end-systolic diameter cut-off for predicting lack of LV normalization was 43 mm. Pre- and postoperative LV dimensions and postoperative LV ejection fraction predicted clinical events during follow-up. Prosthetic valve-related complications occurred in 20.3% during an average 5.6-year follow-up. Freedom from aortic reintervention was 98%, 96.5%, and 85.4% at 1, 5, and 10 years, respectively. Conclusions Young adult patients with increased baseline LV end-systolic diameter or prior cardiac surgery are less likely to achieve LV normalization after AVR. Clinicians should carefully balance the long-term benefits of AVR against procedural risks and future interventions, especially in younger patients. Evidence-based criteria for AVR in severe aortic regurgitation in young adults are crucial to improve outcomes.

Unlocking insights in bicuspid aortic valve management in adult patients: the vital role of cardiac imaging

The bicuspid aortic valve (BAV) presents a multifaceted clinical challenge due to its diverse morphologies and associated complications. This review aims to elucidate the critical role of cardiac imaging in guiding optimal management strategies for BAV patients. BAV, with a prevalence of 1-2%, has genetic underpinnings linked to the NOTCH1 gene mutation. Variability in BAV morphology necessitates tailored surgical approaches. The three primary types of BAV morphology - right-left cusp fusion, right-noncoronary cusp fusion, and left-noncoronary cusp fusion - demand nuanced considerations due to their distinct implications. Valvular dysfunction results in aortic stenosis or regurgitation, attributed to altered valve structure and turbulent hemodynamics. Cardiac imaging modalities, including echocardiography, magnetic resonance imaging, and computerized tomography, are instrumental in assessing valve function, aortic dimensions, and associated complications. Imaging helps predict potential complications, enabling informed treatment decisions. Regular follow-up is crucial to detecting alterations early and intervening promptly. Surgical management options encompass aortic valve repair or replacement, with patient-specific factors guiding the choice. Post-surgical surveillance plays a vital role in preventing complications and optimizing patient outcomes. The review underscores the significance of advanced cardiac imaging techniques in understanding BAV's complexities, facilitating personalized management strategies, and improving patient care. By harnessing the power of multimodal imaging, clinicians can tailor interventions, monitor disease progression, and ultimately enhance the prognosis and quality of life for individuals with BAV.

Paediatric aortic valve replacement: a meta-analysis and microsimulation study

AIMS

To support decision-making in children undergoing aortic valve replacement (AVR), by providing a comprehensive overview of published outcomes after paediatric AVR, and microsimulation-based age-specific estimates of outcome with different valve substitutes.

METHODS AND RESULTS

A systematic review of published literature reporting clinical outcome after paediatric AVR (mean age <18 years) published between 1/1/1990 and 11/08/2021 was conducted. Publications reporting outcome after paediatric Ross procedure, mechanical AVR (mAVR), homograft AVR (hAVR), and/or bioprosthetic AVR were considered for inclusion. Early risks (<30d), late event rates (>30d) and time-to-event data were pooled and entered into a microsimulation model. Sixty-eight studies, of which one prospective and 67 retrospective cohort studies, were included, encompassing a total of 5259 patients (37 435 patient-years; median follow-up: 5.9 years; range 1-21 years). Pooled mean age for the Ross procedure, mAVR, and hAVR was 9.2 ± 5.6, 13.0 ± 3.4, and 8.4 ± 5.4 years, respectively. Pooled early mortality for the Ross procedure, mAVR, and hAVR was 3.7% (95% CI, 3.0%-4.7%), 7.0% (5.1%-9.6%), and 10.6% (6.6%-17.0%), respectively, and late mortality rate was 0.5%/year (0.4%-0.7%/year), 1.0%/year (0.6%-1.5%/year), and 1.4%/year (0.8%-2.5%/year), respectively. Microsimulation-based mean life-expectancy in the first 20 years was 18.9 years (18.6-19.1 years) after Ross (relative life-expectancy: 94.8%) and 17.0 years (16.5-17.6 years) after mAVR (relative life-expectancy: 86.3%). Microsimulation-based 20-year risk of aortic valve reintervention was 42.0% (95% CI: 39.6%-44.6%) after Ross and 17.8% (95% CI: 17.0%-19.4%) after mAVR.

CONCLUSION

Results of paediatric AVR are currently suboptimal with substantial mortality especially in the very young with considerable reintervention hazards for all valve substitutes, but the Ross procedure provides a survival benefit over mAVR. Pros and cons of substitutes should be carefully weighed during paediatric valve selection.

Quality of life after Ross procedure in children

INTRODUCTION

Health-related quality of life in children who have undergone the Ross procedure has not been well characterised. The aim of this study was to characterise health-related quality of life in this cohort and compare to children with other CHD.

METHOD

In this cross sectional, single-centre study, health-related quality of life was assessed in patients who underwent a non-neonatal Ross procedure using the Pediatric Quality of Life Inventory. Ross cohort scores were compared with healthy norms, patients with CHD requiring no surgical intervention or had curative surgery (Severity 2, S2) and patients who were surgically repaired with ≥1 surgical procedure and with significant residual lesion or need for additional surgery (Severity 3, S3). Associations between Pediatric Quality of Life Inventory score and patient factors were also examined.

RESULTS

68 patients completed surveys. Nearly one-sixth of patients had overall scores below the cut-off for at-risk status for impaired health-related quality of life. There was no difference in overall health-related quality of life score between the Ross cohort and healthy children (p = 0.56) and S2 cohort (p = 0.97). Health-related quality of life was significantly higher in the Ross cohort compared to S3 cohort (p = 0.02). This difference was driven by a higher psychosocial health-related quality of life in the Ross cohort as compared to S3 cohort (p = 0.007). Anxiety scores were significantly worse in the Ross cohort compared to both S2 (p = 0.001) and S3 (p = 0.0017), respectively.

CONCLUSION

Children who have undergone a Ross procedure report health-related quality of life equivalent to CHD not requiring therapy and superior to CHD with residual lesions. Despite these reassuring results, providers should be aware of potential anxiety among Ross patients.

The Ross Procedure in Children: Defining the Optimal Age

BACKGROUND

It has been proposed that delaying the Ross procedure to later in childhood, allowing autograft stabilisation and placement of a larger pulmonary conduit, may improve outcomes. However, the effect of age at the time of Ross procedure on outcomes remains unclear.

METHODS

All patients who underwent the Ross procedure between 1995 and 2018 were included in the study. Patients were divided into four groups: infants, age 1 to 5 years, age 5 to 10 years and age 10 to 18 years.

RESULTS

A total of 140 patients underwent the Ross procedure in the study period. Early mortality was 23.3% (7/30) for infants compared to 0% for older children (p<0.001). Survival at 15 years was significantly lower in infants (76.3%±9.9%), compared to children aged 1 to 5 years (90.9%±20.1%), 5 to 10 years (94%±13.3%), and 10 to 18 years (86.7%±10.0%), p=0.01. Freedom from autograft reoperation at 15 years was significantly lower in infants (58.4%±16.2%), compared to children aged 1 to 5 years (77.1%±14.9%), 5 to 10 years (84.2%±6.0%) and 10 to 18 years (87.8%±9.0%), p=0.01. Overall freedom from reoperation at 15 years was 13.0%±6.0% for infants, 24.2%±9.0% for children aged 1 to 5 years, 46.7%±15.8% for children aged 5 to 10 years, and 78.4%±10.4%, p<0.001.

CONCLUSIONS

The Ross procedure performed after 10 years of age appears to be associated with improved freedom from reoperation, primarily due to a reduction in reoperation on the pulmonary conduit.

Aortic valve repair in the pediatric population: emerging role of aortic valve neocuspidization (AVNeo procedure)

Management of aortic valve diseases in children is challenging owing to the quality and quantity of the native tissue for repair, limitations in the currently available biological materials to supplement the repair and to achieve a long-lasting durable repair in an annulus where there is still growth potential. The aortic valve neocuspidization (AVNeo) procedure has emerged as a versatile alternative strategy in the armamentarium of pediatric aortic valve reconstructions that are currently available. In this review article, the focus of the discussion will be on the various aortic valve repair procedures in the pediatric population, with a special emphasis on the emerging role of AVNeo procedure in pediatrics and its outcomes.

The Ross Operation in Young Patients: A 15-Year Experience Focused on Right Ventricle to Pulmonary Artery Conduit Outcomes

Background

Data on long-term outcomes of the Ross operation in children and young adult patients are limited. The best pulmonary valve substitute for the right ventricular outflow tract reconstruction remains uncertain. This study aimed to assess the outcomes of right ventricular outflow tract reconstruction in the Ross operation in young patients using various pulmonary valve substitutes at a single institution. In addition, a comparison of reintervention rates between patients younger than 18 years and those older than 18 years was performed.

Methods

The study assessed all patients (N = 110) who underwent the Ross operation at the University Hospital of Bordeaux, France, between 2004 and 2020.

Results

The median follow-up time was 4.2 years, and the median age at operation was 15.9 years. There was no operative mortality and 1 late noncardiac death (0.8%). The overall survival rate at 10 years was 99.2%. The need for right ventricular outflow tract reoperation was lower with the pulmonary homograft compared with the Contegra conduit and Freestyle bioprosthesis: 94.3%, 93.8%, and 80% at 5 years, respectively, and 94.3%, 72.3%, and 34.3% at 10 years, respectively (P = 0.011). The probability of reintervention was not significantly different at 10 years among children vs adults (P = 0.22).

Conclusions

The Ross procedure in children and young adults was associated with a lower requirement for right ventricular outflow tract reoperation when pulmonary homografts were used instead of xenografts.

The Ross Procedure in Adolescence and Beyond: Are There Still Contraindications?

The Ross procedure is an excellent operation to treat children and adults with aortic valve disease. Compared to prosthetic aortic valve replacement, it provides important clinical benefits in terms of survival, hemodynamics, freedom from valve-related complications, and durability, especially in women of childbearing age. However, the Ross procedure is a longer and technically more challenging operation. As a result, the choice of procedure should be driven by patient anatomy and clinical characteristics. This highlights the importance of concentrating care in Ross reference centers where surgical expertise and experience are present to ensure patient safety and long-term effectiveness of the operation. This manuscript reviews the major and relative contraindications to the Ross procedure.

Pregnancy outcomes in women following the Ross procedure

INTRODUCTION

The Ross procedure, where a pulmonary autograft (neoaorta) replaces the aortic valve, has excellent long-term outcomes in patients with congenital aortic valve disease. However, there are reports of neoaortic dilatation and dissection. An increasing number of women are wishing to become pregnant following the Ross procedure, but little is known about the occurrence and risks of neoaortic dilatation and complications in pregnancy. We investigated neoaorta function and outcomes in pregnancy following the Ross procedure.

METHODS

This retrospective study investigated women post-Ross procedure at a tertiary ACHD unit between 1997 and 2021. Imaging evaluated neoaortic root dimensions and regurgitation pre-, and post- pregnancy, compared with matched non-pregnant controls. Primary endpoints were change in neoaortic dimensions, degree of regurgitation and adverse maternal outcomes.

RESULTS

Nineteen pregnancies in 12 women were included. The mean change in neoaortic root diameter post-pregnancy was 1.8 mm (SD 3.4) (p = 0.017). There was no significant change in neoaortic dimensions in matched controls during follow-up. There were no cases of dissection, arrhythmia, acute coronary syndrome, or maternal mortality. Three deliveries were pre-term, including one emergency Caesarean section due to maternal cardiac decompensation, requiring aortic root replacement post-partum but there were no neonatal deaths.

CONCLUSIONS

Pregnancy following the Ross procedure is associated with neoaortic dilatation, and pregnancy is generally well tolerated. Although adverse maternal outcomes are uncommon, there are still rare cases of cardiac complications in and around the time of pregnancy. These findings emphasise the need for accessible pre-pregnancy counselling, risk stratification and careful surveillance through pregnancy by specialist cardio-obstetric multi-disciplinary teams.

Biological Scaffolds for Congenital Heart Disease

Congenital heart disease (CHD) is the most predominant birth defect and can require several invasive surgeries throughout childhood. The absence of materials with growth and remodelling potential is a limitation of currently used prosthetics in cardiovascular surgery, as well as their susceptibility to calcification. The field of tissue engineering has emerged as a regenerative medicine approach aiming to develop durable scaffolds possessing the ability to grow and remodel upon implantation into the defective hearts of babies and children with CHD. Though tissue engineering has produced several synthetic scaffolds, most of them failed to be successfully translated in this life-endangering clinical scenario, and currently, biological scaffolds are the most extensively used. This review aims to thoroughly summarise the existing biological scaffolds for the treatment of paediatric CHD, categorised as homografts and xenografts, and present the preclinical and clinical studies. Fixation as well as techniques of decellularisation will be reported, highlighting the importance of these approaches for the successful implantation of biological scaffolds that avoid prosthetic rejection. Additionally, cardiac scaffolds for paediatric CHD can be implanted as acellular prostheses, or recellularised before implantation, and cellularisation techniques will be extensively discussed.

Ross Procedure in Children: The Society of Thoracic Surgeons Congenital Heart Surgery Database Analysis

BACKGROUND

Single-center studies have demonstrated excellent results for the Ross procedure in children. We aimed to evaluate national variation in clinical outcomes using The Society of Thoracic Surgeons Congenital Heart Surgery Database.

METHODS

The database was used to identify 2805 children undergoing the Ross procedure from 2000 through 2018, comprising 163 neonates (<30 days, 5.8%), 448 infants (30-365 days, 16.0%), 1444 children (1-12 years, 51.5%), and 750 teenagers (13-17 years, 26.7%). Centers were divided into terciles by procedural volume. Multivariable logistic regression was used to identify predictors of a composite outcome of operative mortality, neurologic deficit, or renal failure requiring dialysis.

RESULTS

Neonates and infants were more likely to present with aortic stenosis than children and teenagers (61.7% [n = 377] vs 34.6% [n = 760]; P < .01) and have risk factors including preoperative shock (9.2% [n = 56] vs 0.4% [n = 8]; P < .01). Operative mortality was 24.1% (n = 39) in neonates, 11.2% (n = 50) in infants, 1.5% (n = 21) in children , and 0.8% (n = 6) in teenagers (P < .01). Independent predictors of the composite outcome in children aged <1 year included neonatal age (odds ratio [OR], 3.0; 95% CI, 1.9-4.8), low-volume center (OR, 2.1; 95% CI, 1.1-3.9), and procedure year (OR, 0.7; 95% CI, 0.5-0.9 per 5 years). In children aged ≥1 year, no association was found between center volume, procedure year, and outcome.

CONCLUSIONS

The Ross procedure is being performed with low mortality in children aged ≥1 year throughout North America. High-volume centers have improved outcomes in children aged <1 year, who have different anatomic characteristics and risk profiles.

Long-term Outcomes of the Ross Procedure for Young Patients with Aortic Valve Disease

To define current role of the Ross operation in young patients, the outcome in those followed longer than 20 years were assessed. Between 1994 and 2020, 81 consecutive patients, 70 of 11 male and/or female, mean age 27 years underwent Ross procedure, accruing 20 years of follow-up or longer. Sixty-four had bicuspid valve (79%) and 54 (67%) aortic insufficiency, while 15 (19%) had undergone prior operations. Surgery consisted in root replacement in 53 patients, cylinder inclusion in 20 and sub-coronary graft in 8. There were 7 late deaths in 80 hospital survivors (median follow-up 21 years, IQR 20-23), with 88% ± 5% survival at 25 years. Thirty-four patients required left, 6 left and/or right and 1 right heart valve reoperation, on average 13 years after Ross procedure. Reoperation was valve-sparing in 18 (45%) patients and valve and/or root replacement in 22. Ten (24%) reoperated patients required a second reoperation 18 years after Ross procedure. Freedom from autograft reoperation was 46% ± 6%, while from autograft valve replacement was 60% ± 7%, thanks to autograft valve-sparing. Freedom from isolated right valve reoperation was 98% ± 4%. No mortality was associated with any of the 51 reoperations. Root technique was associated with reoperation (P = 0.024). Age at follow-up was 50 years (IQR 36-60), with 70 (96%) patients in NYHA class I and 6 (55%) women carrying out pregnancies. Young patients undergoing the Ross procedure enjoy unprecedented survival well into the third decade of follow-up, even when faced with reoperation. At 25 years risk of autograft reoperation is consistent, while negligible for homograft. Technical improvements at operation and valve-sparing at reoperation may prolong autograft valve durability.

Ross procedure in neonates and infants: A valuable operation with defined limits

OBJECTIVE

The Ross procedure is an important tool that offers autologous tissue repair for severe left ventricular outflow tract (LVOT) pathology. Previous reports show that risk of mortality is highest among neonates and infants. We analyzed our institutional experience within this patient cohort to identify factors that most affect clinical outcome.

METHODS

A retrospective chart review identified all Ross operations in neonates and infants at our institution over 27 years. The entire study population was analyzed to determine risk factors for mortality and define outcomes for survival and reintervention.

RESULTS

Fifty-eight patients underwent a Ross operation at a median age of 63 (range, 9-156) days. Eighteen (31%) were neonates. Eleven (19%) patients died before hospital discharge. Multiple regression analysis of the entire cohort identified young age (hazard ratio [HR], 1.037; P = .0045), Shone complex (HR, 17.637; P = .009), and interrupted aortic arch with ventricular septal defect (HR, 16.01; P = .031) as independent predictors of in-hospital mortality. Receiver operating characteristic analysis (area under the curve, 0.752) indicated age younger than 84 days to be the inflection point at which mortality risk increases. Of the 47 survivors, there were 2 late deaths with a mean follow-up of 6.7 (range, 2.1-13.1) years. Three patients (6%) required LVOT reintervention at 3, 8, and 17.5 years, respectively, and 26 (55%) underwent right ventricular outflow tract reintervention at a median of 6 (range, 2.5-10.3) years.

CONCLUSIONS

Ross procedure is effective in children less than one year of age with left sided obstructive disease isolated to the aortic valve and/or aortic arch. Patients less than 3 months of age with Shone or IAA/VSD are at higher risk for morbidity and mortality. Survivors experience excellent intermediate-term freedom from LVOT reintervention.

Ross Procedure Versus Mechanical Versus Bioprosthetic Aortic Valve Replacement: A Network Meta-Analysis

Background The Ross operation appears to restore normal survival in young and middle-aged adults with aortic valve disease. However, there are limited data comparing it with conventional aortic valve replacement. Herein, we compared outcomes of the Ross procedure with mechanical and bioprosthetic aortic valve replacement (M-AVR and B-AVR, respectively). Methods and Results MEDLINE and EMBASE were searched through March 2022 to identify randomized controlled trials and propensity score-matched studies that investigated outcomes of patients aged ≥16 years undergoing the Ross procedure, M-AVR, or B-AVR. The systematic literature search identified 2 randomized controlled trials and 8 propensity score-matched studies involving a total of 4812 patients (Ross: n=1991; M-AVR: n=2019; and B-AVR: n=802). All-cause mortality was significantly lower in the Ross procedure group compared with M-AVR (hazard ratio [HR] [95% CI], 0.58 [0.35-0.97]; P=0.035) and B-AVR (HR [95% CI], 0.32 [0.18-0.59]; P<0.001) groups. The reintervention rate was lower after the Ross procedure and M-AVR compared with B-AVR, whereas it was higher after the Ross procedure compared with M-AVR. Major bleeding rate was lower after the Ross procedure compared with M-AVR. Long-term stroke rate was lower following the Ross procedure compared with M-AVR and B-AVR. The rate of endocarditis was also lower after the Ross procedure compared with B-AVR. Conclusions Improved long-term outcomes of the Ross procedure are demonstrated compared with conventional M-AVR and B-AVR options. These results highlight a need to enhance the recognition of the Ross procedure and revisit current guidelines on the optimal valve substitute for young and middle-aged patients.

Outcomes of the Ross procedure in young adults with previous aortic valve interventions

OBJECTIVES

Contemporarily modified Ross procedure continues to deliver excellent outcomes and remains part of the treatment strategy for aortic valve disease in the young adult population. The aim of this study was to assess whether Ross procedure carried out as a second or subsequent intervention for aortic valve disease carries similar risk and long-term benefit, when compared to Ross procedure for the first-time aortic valve replacement.

METHODS

A total of 158 patients aged 16-60 years from a single congenital cardiac centre between 1997 and 2020 were included. The sample was split into 2 subgroups, based on the history of previous aortic valve interventions prior to the Ross procedure. Primary outcomes were defined as survival and pulmonary autograft failure. Coarsened exact matching was used to balance for covariates.

RESULTS

A total of 103 patients underwent primary Ross and 55 underwent secondary Ross with a mean follow-up of 7.8 years. Twenty-two patients underwent 28 reoperations during follow-up. Forty-nine well-matched pairs were obtained through matching. Freedom from pulmonary autograft failure at 10 years was 84.5% in the primary group vs 100% in the secondary group (P = 0.021). Five- and ten-year survival were identical, 97.5% in the primary group vs 95.6% in the secondary group (P = 0.53). Male sex and era were found to be predictors of neoaortic root dilatation.

CONCLUSIONS

The lower incidence of graft failure seen in secondary Ross could justify a stepwise approach to aortic valve intervention. Ross procedure delivers excellent outcomes in the adult population with no difference in survival for primary or secondary Ross.

Perspectives on pediatric congenital aortic valve stenosis: Extracellular matrix proteins, post translational modifications, and proteomic strategies

In heart valve biology, organization of the extracellular matrix structure is directly correlated to valve function. This is especially true in cases of pediatric congenital aortic valve stenosis (pCAVS), in which extracellular matrix (ECM) dysregulation is a hallmark of the disease, eventually leading to left ventricular hypertrophy and heart failure. Therapeutic strategies are limited, especially in pediatric cases in which mechanical and tissue engineered valve replacements may not be a suitable option. By identifying mechanisms of translational and post-translational dysregulation of ECM in CAVS, potential drug targets can be identified, and better bioengineered solutions can be developed. In this review, we summarize current knowledge regarding ECM proteins and their post translational modifications (PTMs) during aortic valve development and disease and contributing factors to ECM dysregulation in CAVS. Additionally, we aim to draw parallels between other fibrotic disease and contributions to ECM post-translational modifications. Finally, we explore the current treatment options in pediatrics and identify how the field of proteomics has advanced in recent years, highlighting novel characterization methods of ECM and PTMs that may be used to identify potential therapeutic strategies relevant to pCAVS.

Ross Procedure in Neonate and Infant Populations: A Meta-Analysis Review

Objective

This study aims to perform a meta-analysis of early and late outcomes of the Ross/Ross-Konno procedures in neonates/infants.

Methods

A meta-analysis was performed in accordance with PRISMA guidelines. We used Ovid versions of MEDLINE/PubMed for relevant studies and included those that reported Ross/Ross-Konno operations in neonates/infants and at least one of the predetermined clinical outcomes. I2 and double arcsine methods assessed the heterogeneity between pooled estimates. We used a random-effect model to account for heterogeneity with MetaXL. We calculated point estimates of a pooled estimates along with its 95% CI.

Results

587 neonate/infant patients were included with median age of 87.5 days old. The follow-up range was five days to 23 years. Early mortality reported in 25 studies with pooled estimates of 18.3% (95% CI: 13.6%-23.5%). Estimates ranged from 0% to 50% with relatively substantial heterogeneity ( P = .01, I2 = 48.6%). Late mortality reported in 22 studies with pooled incidence of 9.7% (95% CI: 5.9%-14.3%). Estimates ranged from 0% to 53% with relatively substantial heterogeneity ( P = .01, I2 = 46.1%). Autograft reintervention reported in 18 studies with pooled estimate of 19.2% (95% CI: 7.3%-34.5%). Estimates ranged from 0% to 81.8% with high heterogeneity ( P < .001, I2 = 90.5%). Right ventricle-to-pulmonary artery conduit reintervention reported in 16 studies with pooled estimates of 32.0% (95% CI: 20.9%-44.12%). Estimates ranged from 0% to 92.3% with high heterogeneity ( P < .001, I2 = 75.9%).

Conclusions

The data suggest that the Ross/Ross-Konno procedure in neonates/infants still carries significant risk of early/late mortality and autograft/conduit reintervention. The high variability of results among centers confirms the need for surgical expertise and good patient selection. Prospective multicenter studies are warranted to investigate the rate of autograft reintervention and the impact on long-term survival in this specific population.

Biomechanics of Pulmonary Autograft as Living Tissue: A Systematic Review

Introduction: The choice of valve substitute for aortic valve surgery is tailored to the patient with specific indications and contraindications to consider. The use of an autologous pulmonary artery (PA) with a simultaneous homograft in the pulmonary position is called a Ross procedure. It permits somatic growth and the avoidance of lifelong anticoagulation. Concerns remain on the functionality of a pulmonary autograft in the aortic position when exposed to systemic pressure. Methods: A literature review was performed incorporating the following databases: Pub Med (1996 to present), Ovid Medline (1958 to present), and Ovid Embase (1982 to present), which was run on 1 January 2022 with the following targeted words: biomechanics of pulmonary autograft, biomechanics of Ross operation, aortic valve replacement and pulmonary autograph, aortic valve replacement and Ross procedure. To address the issues with heterogeneity, studies involving the pediatric cohort were also analyzed separately. The outcomes measured were early- and late-graft failure alongside mortality. Results: a total of 8468 patients were included based on 40 studies (7796 in pediatric cohort and young adult series and 672 in pediatric series). There was considerable experience accumulated by various institutions around the world. Late rates of biomechanical failure and mortality were low and comparable to the general population. The biomechanical properties of the PA were superior to other valve substitutes. Mathematical and finite element analysis studies have shown the potential stress-shielding effects of the PA root. Conclusion: The Ross procedure has excellent durability and longevity in clinical and biomechanical studies. The use of external reinforcements such as semi-resorbable scaffolds may further extend their longevity.

Surgical Management of Complex Aortic Valve Disease in Young Adults: Repair, Replacement, and Future Alternatives

The ideal aortic valve substitute in young adults remains unknown. Prosthetic valves are associated with a suboptimal survival and carry a significant risk of valve-related complications in young patients, mainly reinterventions with tissue valves and, thromboembolic events and major bleeding with mechanical prostheses. The Ross procedure is the only substitute that restores a survival curve similar to that of a matched general population, and permits a normal life without functional limitations. Though the risk of reintervention is the Achilles' heel of this procedure, it is very low in patients with aortic stenosis and can be mitigated in patients with aortic regurgitation by tailored surgical techniques. Finally, the Ozaki procedure and the transcatheter aortic valve implantation are seen by many as future alternatives but lack evidence and long-term follow-up in this specific patient population.

The Year in Review: Anesthesia for Congenital Heart Disease 2021

This review focuses on the literature published during the calendar year 2021 that is of interest to anesthesiologists taking care of children and adults with congenital heart disease. Four major themes are discussed, including cardiovascular disease in children with COVID-19, aortic valve repair and replacement, bleeding and coagulation, and enhanced recovery after surgery (ERAS).

Natural Polymers in Heart Valve Tissue Engineering: Strategies, Advances and Challenges

In the history of biomedicine and biomedical devices, heart valve manufacturing techniques have undergone a spectacular evolution. However, important limitations in the development and use of these devices are known and heart valve tissue engineering has proven to be the solution to the problems faced by mechanical and prosthetic valves. The new generation of heart valves developed by tissue engineering has the ability to repair, reshape and regenerate cardiac tissue. Achieving a sustainable and functional tissue-engineered heart valve (TEHV) requires deep understanding of the complex interactions that occur among valve cells, the extracellular matrix (ECM) and the mechanical environment. Starting from this idea, the review presents a comprehensive overview related not only to the structural components of the heart valve, such as cells sources, potential materials and scaffolds fabrication, but also to the advances in the development of heart valve replacements. The focus of the review is on the recent achievements concerning the utilization of natural polymers (polysaccharides and proteins) in TEHV; thus, their extensive presentation is provided. In addition, the technological progresses in heart valve tissue engineering (HVTE) are shown, with several inherent challenges and limitations. The available strategies to design, validate and remodel heart valves are discussed in depth by a comparative analysis of in vitro, in vivo (pre-clinical models) and in situ (clinical translation) tissue engineering studies.

Truncal valve leaflet reconstruction with autologous pericardium in a neonate

A boy diagnosed with persistent truncus arteriosus and severe truncal valve regurgitation had uncontrollable heart failure. Thus, truncal valve repair, ventricular septal defect closure, and right ventricular outflow tract reconstruction were performed on the second day of life. We report about a neonate with severe truncal valve regurgitation who was successfully treated with autologous pericardial truncal valve leaflet reconstruction.

Improved Outcomes Following the Ross Procedure Compared With Bioprosthetic Aortic Valve Replacement

BACKGROUND

The ideal aortic valve substitute for young and middle-aged adults remains elusive.

OBJECTIVES

This study sought to compare the long-term outcomes of patients undergoing the Ross procedure and those receiving bioprosthetic aortic valve replacements (AVRs).

METHODS

Consecutive patients aged 16-60 years who underwent a Ross procedure or surgical bioprosthetic AVR at the Toronto General Hospital between 1990 and 2014 were identified. Propensity score matching was used to account for differences in baseline characteristics. The primary outcome was all-cause mortality. Secondary outcomes included valve reintervention, valve deterioration, endocarditis, thromboembolic events, and permanent pacemaker implantation.

RESULTS

Propensity score matching yielded 108 pairs of patients. The median age was 41 years (IQR: 34-47 years). Baseline characteristics were similar between the matched groups. There was no operative mortality in either group. Mean follow-up was 14.5 ± 7.2 years. All-cause mortality was lower following the Ross procedure (HR: 0.35; 95% CI: 0.14-0.90; P = 0.028). Using death as a competing risk, the Ross procedure was associated with lower rates of reintervention (HR: 0.21; 95% CI: 0.10-0.41; P < 0.001), valve deterioration (HR: 0.25; 95% CI: 0.14-0.45; P < 0.001), thromboembolic events (HR: 0.15; 95% CI: 0.05-0.50; P = 0.002), and permanent pacemaker implantation (HR: 0.22; 95% CI: 0.07-0.64; P = 0.006).

CONCLUSIONS

In this propensity-matched study, the Ross procedure was associated with better long-term survival and freedom from adverse valve-related events compared with bioprosthetic AVR. In specialized centers with sufficient expertise, the Ross procedure should be considered the primary option for young and middle-aged adults undergoing AVR.

Supporting the Ross procedure: preserving root physiology while mitigating autograft dilatation

PURPOSE OF REVIEW

The purpose of this article is to describe the optimized approach to nonrepairable aortic valve disease in young adults with a Ross procedure, while preserving the dynamic physiology of the aortic root.

RECENT FINDINGS

As the techniques for supporting pulmonary autografts continue to be refined, and the applicability of the Ross procedure continues to expand, an assessment of the various techniques based on aortic root physiology is warranted. Semi-resorbable scaffolds show promise in ovine models for improving the Ross procedure. Recent long-term outcomes for the Dacron inclusion technique in comparison to more physiologic methods of support emphasize the importance of balancing the prevention of early dilatation with the preservation of root haemodynamics. As this review will synthesize, the dynamic physiology of the root may be preserved even in patients at a higher risk of autograft dilatation.

SUMMARY

The favourable long-term outcomes of the Ross procedure can be partly attributed to the ability of the autograft to restore dynamism to the neoaortic root. Patient-specific modifications that respect root physiology can tailor the Ross procedure to address each patient's risk factors for early dilatation and late failure. As such, the Ross procedure should be recognized as an increasingly favourable solution for a wide spectrum of nonpreservable aortic valve disease in young adults.

Understanding Pulmonary Autograft Remodeling After the Ross Procedure: Stick to the Facts

The Ross, or pulmonary autograft, procedure presents a fascinating mechanobiological scenario. Due to the common embryological origin of the aortic and pulmonary root, the conotruncus, several authors have hypothesized that a pulmonary autograft has the innate potential to remodel into an aortic phenotype once exposed to systemic conditions. Most of our understanding of pulmonary autograft mechanobiology stems from the remodeling observed in the arterial wall, rather than the valve, simply because there have been many opportunities to study the walls of dilated autografts explanted at reoperation. While previous histological studies provided important clues on autograft adaptation, a comprehensive understanding of its determinants and underlying mechanisms is needed so that the Ross procedure can become a widely accepted aortic valve substitute in select patients. It is clear that protecting the autograft during the early adaptation phase is crucial to avoid initiating a sequence of pathological remodeling. External support in the freestanding Ross procedure should aim to prevent dilatation while simultaneously promoting remodeling, rather than preventing dilatation at the cost of vascular atrophy. To define the optimal mechanical properties and geometry for external support, the ideal conditions for autograft remodeling and the timeline of mechanical adaptation must be determined. We aimed to rigorously review pulmonary autograft remodeling after the Ross procedure. Starting from the developmental, microstructural and biomechanical differences between the pulmonary artery and aorta, we review autograft mechanobiology in relation to distinct clinical failure mechanisms while aiming to identify unmet clinical needs, gaps in current knowledge and areas for further research. By correlating clinical and experimental observations of autograft remodeling with established principles in cardiovascular mechanobiology, we aim to present an up-to-date overview of all factors involved in extracellular matrix remodeling, their interactions and potential underlying molecular mechanisms.

The effectiveness and safety of pulmonary autograft as living tissue in Ross procedure: a systematic review

BACKGROUND

Reports on effectiveness and safety after the implant of pulmonary autograft (PA) living tissue in Ross procedure, to treat both congenital and acquired disease of the aortic valve and left ventricular outflow tract (LVOT), show variable durability results. We undertake a quantitative systematic review of evidence on outcome after the Ross procedure with the aim to improve insight into outcome and potential determinants.

METHODS

A systematic search of reports published from October 1979 to January 2021 was conducted (PubMed, Ovid Medline, Ovid Embase and Cochrane library) reporting outcomes after the Ross procedure in patients with diseased aortic valve with or without LVOT. Inclusion criteria were observational studies reporting on mortality and/or morbidity after autograft aortic valve or root replacement, completeness of follow-up >90%, and study size n≥30. Forty articles meeting the inclusion criteria were allocated to two categories: pediatric patient series and young adult patient series. Results were tabulated for a clearer presentation.

RESULTS

A total of 342 studies were evaluated of which forty studies were included in the final analysis as per the eligibility criteria. A total of 8,468 patients were included (7,796 in pediatric cohort and young adult series and 672 in pediatric series). Late mortality rates were remarkably low alongside similar age-matched mortality with the general population in young adults. There were differences in implantation techniques as regard the variability in stress and the somatic growth that recorded conflicting outcomes regarding the miniroot vs the subcoronary approach.

DISCUSSION

The adaptability of lung autograft to allow for both stress variability and somatic growth make it an ideal conduit for Ross's operation. The use of the miniroot technique over subcoronary implantation for better adaptability to withstand varying degrees of stress is perhaps more applicable to different patient subgroups.

Aortic stenosis in chronic kidney disease: challenges in diagnosis and treatment

Chronic kidney disease (CKD) is becoming increasingly common and is associated with development and rapid progression of aortic stenosis (AS). Patients with AS and CKD have higher mortality rates than those with AS of similar severity and normal kidney function. The diagnosis of severe AS in patients with CKD is often challenging due to alterations in haemodynamics and heart structure, and integration of data from multiple imaging modalities may be required. When indicated, the definitive treatment for severe AS is aortic valve replacement. Patients with CKD are candidates for bioprosthetic valve replacement (surgical or transcatheter aortic valve implantation) or mechanical valve replacement. However, for patients with CKD, lifetime management is complex, as patients with CKD have a higher competing risk of bioprosthetic structural valve deterioration, bleeding in the setting of systemic anticoagulation and mortality related to CKD itself. The involvement of a heart-kidney multidisciplinary team in the care of patients with CKD and severe AS is ideal to navigate the complexities of diagnosis and management decisions.

Multicentre comparative analysis of long-term outcomes after aortic valve replacement in children

OBJECTIVE

The ideal valve substitute for surgical intervention of congenital aortic valve disease in children remains unclear. Data on outcomes beyond 10-15 years after valve replacement are limited but important for evaluating substitute longevity. We aimed to describe up to 25-year death/cardiac transplant by type of valve substitute and assess the potential impact of treatment centre. Our hypothesis was that patients with pulmonic valve autograft would have better survival than mechanical prosthetic.

METHODS

This is a retrospective cohort study from the Pediatric Cardiac Care Consortium, a multi-institutional US-based registry of paediatric cardiac interventions, linked with the National Death Index and United Network for Organ Sharing through 2019. Children (0-20 years old) receiving aortic valve replacement (AVR) from 1982 to 2003 were identified. Kaplan-Meier transplant-free survival was calculated, and Cox proportional hazard models estimated hazard ratios for mechanical AVR (M-AVR) versus pulmonic valve autograft.

RESULTS

Among 911 children, the median age at AVR was 13.4 years (IQR=8.4-16.5) and 73% were male. There were 10 cardiac transplants and 153 deaths, 5 after transplant. The 25-year transplant-free survival post AVR was 87.1% for autograft vs 76.2% for M-AVR and 72.0% for tissue (bioprosthetic or homograft). After adjustment, M-AVR remained related to increased mortality/transplant versus autograft (HR=1.9, 95% CI=1.1 to 3.4). Surprisingly, survival for patients with M-AVR, but not autograft, was lower for those treated in centres with higher in-hospital mortality.

CONCLUSION

Pulmonic valve autograft provides the best long-term outcomes for children with aortic valve disease, but AVR results may depend on a centre's experience or patient selection.

Open-sleeve technique: A new approach for aortic valve leaflet reconstruction in small children

A boy was diagnosed with a unicuspid aortic valve with severe stenosis at birth. Percutaneous balloon aortic valvuloplasty was performed four times; however, he had severe heart and growth failure. Thus, aortic valve repair was performed at age 2 years and 6 months. He weighed 6.6 kg. The aortic valve annulus diameter was 9.8 mm (z value = 0.43). We report on a small toddler with congenital aortic stenosis who was successfully treated with autologous pericardial aortic valve leaflet reconstruction using the open-sleeve technique.

Ross for Valve replacement In AduLts (REVIVAL) pilot trial: rationale and design of a randomised controlled trial

INTRODUCTION

In non-elderly adults, aortic valve replacement (AVR) with conventional prostheses yield poor long-term outcomes. Recent publications suggest a benefit of the Ross procedure over conventional AVR and highlight the need for high-quality randomised controlled trial (RCTs) on the optimal AVR. We have initiated a pilot trial assess two feasibility criteria and one assumption: (1) evaluate the capacity to enrol six patients per centre per year in at least five international centre, (2) validate greater than 90% compliance with allocation and (3) to validate the proportion of mechanical (≥65%) vs biological (≤35%) valves in the conventional arm.

METHODS AND ANALYSIS

Ross for Valve replacement In AduLts (REVIVAL) is a multinational, expertise-based RCT in adults aged 18-60 years undergoing AVR, comparing the Ross procedure versus one of the alternative approaches (mechanical vs stented or stentless bioprosthesis). The feasibility objectives will be assessed after randomising 60 patients; we will then make a decision regarding whether to expand the trial with the current protocol. We will ultimately examine the impact of the Ross procedure as compared with conventional AVR in non-elderly adults on survival free of valve-related life-threatening complications (major bleeding, systemic thromboembolism, valve thrombosis and valve reoperation) over the duration of follow-up. The objectives of the pilot trial will be analysed using descriptive statistics. In the full trial, the intention-to-treat principle will guide all primary analyses. A time-to-event analysis will be performed and Kaplan-Meier survival curves with comparison between groups using a log rank test will be presented.

ETHICS AND DISSEMINATION

REVIVAL will answer whether non-elderly adults benefit from the Ross procedure over conventional valve replacement. The final results at major meetings, journals, regional seminars, hospital rounds and via the Reducing Global Perioperative Risk Multimedia Resource Centre.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT03798782 PROTOCOL VERSION: January 29, 2019 (Final Version 1.0).

The Ross procedure is an excellent operation in non-repairable aortic regurgitation: insights and techniques

The Ross procedure is the best operation to treat aortic stenosis (AS) in young and middle-aged adults. However, its role in non-repairable aortic regurgitation (AR) remains debated since many historical series have reported an increased risk of pulmonary autograft dilatation and subsequent need for reintervention in these patients. Some have attributed these findings to an unrecognized and poorly characterized inherited genetic defect that prevents adaptive remodelling of the pulmonary autograft. Herein, we review the contemporary evidence surrounding the use of the Ross procedure in young adults with AR and put forth the argument that with proper technical refinements, the Ross procedure may still be the best operation to treat these patients. We believe that by tailoring the operation to the patient's anatomy and ensuring strict postoperative blood pressure control, one can achieve excellent results with the Ross procedure, including in this challenging patient population.

The Ross procedure is the optimal solution for young adults with unrepairable aortic valve disease

While aortic valve repair remains the ideal intervention to restore normal valvular function, the optimal aortic valve substitute for patients with a non-repairable aortic valve remains an ongoing subject for debate. In particular, younger patients with a non-repairable valve represent a unique challenge because of their active lifestyle and long life expectancy, which carries a higher cumulative risk of prosthesis-related complications. The Ross procedure, unlike prosthetic or homograft aortic valve replacement (AVR), provides an expected survival equivalent to that of the age and gender-matched general population. Contemporary data has shown that the Ross procedure can be performed safely in centers with expertise, and is associated with improved valvular durability, hemodynamics and quality of life.

The Ross procedure in children: a systematic review

Background

The Ross procedure involves autograft transplantation of the native pulmonary valve into the aortic position and reconstruction of the right ventricular outflow tract (RVOT) with a homograft. The operation offers the advantages of a native valve with excellent hemodynamic performance, the avoidance of anticoagulation, and growth potential. Conversely, the operation is technically demanding and imposes the risk of turning single-valve disease into double-valve disease. This systematic review reports outcomes of pediatric patients undergoing the Ross procedure.

Methods

An electronic search identified studies reporting outcomes on pediatric patients (mean age <18 years, max age <21 years) undergoing the Ross procedure. Long-term outcomes, including early mortality, late mortality, sudden unexpected unexplained death, reoperation due to failure of the pulmonary autograft or RVOT reconstruction, thromboembolic events, bleeding events, and endocarditis-related complications, were evaluated.

Results

Upon review of 2,035 publications, 30 studies and 3,156 pediatric patients were included. Patients had a median age of 9.5 years and median follow-up period of 5.7 years. Early mortality rates varied from 0.0 to 17.0% and were increased in the neonatal population. Late mortality rates were much lower (0.04-1.83%/year). Reoperation due to pulmonary autograft failure occurred at rates of 0.37-2.81%/year and reoperation due to RVOT reconstruction failure was required at rates of 0.34-4.76%/year. Thromboembolic, bleeding, and endocarditis events were reported to occur at rates of 0.00-0.58, 0.00-0.39, and 0.00-1.68%/year, respectively.

Conclusions

The Ross operation offers a durable aortic valve replacement (AVR) option in the pediatric population that offers favorable survival, excellent hemodynamics, growth potential, decreased risk of complications, and avoidance of anticoagulation. Larger multi-institutional registries focusing on pediatric patients are necessary to provide more robust evidence to further support use of the Ross procedure in this population.

Outcome of Pulmonary Autograft After the Ross Procedure

BACKGROUND

The purpose of this study was to assess autograft function after the Ross procedure and to review surgical outcomes associated with autograft reoperations.

METHODS

This is a retrospective study of patients undergoing the Ross procedure since 1993. Autograft function and autograft reoperation were studied. Autograft failure was defined as more than moderate autograft regurgitation or autograft dilatation to more than 50 mm diameter or z-score of more than +4 in children. One hospital death was excluded from analysis as were patients with unknown late autograft status.

RESULTS

Among 75 patients analyzed, preoperative diagnosis before the Ross procedure included aortic regurgitation in 26, aortic stenosis in 19, combined lesions in 28, and 2 mechanical valve malfunctions. Median age at the Ross procedure was 12.1 (0.4-43.6) years with 44 children less than 15 years old. Six patients had greater than mild autograft regurgitation at post-Ross hospital discharge. During median follow-up of 14.9 years, there were 23 autograft failures. Eighteen autograft reoperations were performed on 17 patients (13 children), including 12 aortic valve replacements, 5 aortic root replacements (including 1 valve-sparing root replacement), and 1 Konno procedure. Freedom from autograft failure and autograft reoperation at 20 years after the Ross procedure was 52.0% and 66.3%, respectively. Multivariate analysis identified greater than mild autograft regurgitation at hospital discharge from Ross procedure as a risk factor for autograft failure (P < .01). All patients who underwent autograft reoperation survived and had good health status at a median of 6.9 years after the reoperation.

CONCLUSIONS

The Ross procedure is effective in delaying prosthetic aortic valve replacement, although the time-related risk of autograft failure is a real consideration.