A multicentre evaluation of the autograft procedure for young patients undergoing aortic valve replacement: update on the German Ross Registry†

Ex vivo evaluation of 3 different right ventricular outflow tract substitutes

OBJECTIVES

The Ross procedure represents an excellent treatment option in younger patients with aortic stenosis but is limited by poor availability of homografts. In this study, we investigated the hydrodynamic performance of 3 different types of right ventricular outflow tract replacement with pericardium or synthetic material.

METHODS

Three different types of valved conduits were constructed using pericardium and/or synthetic material (Group PEPE: pericardial cusps and pericardial conduit, Group PEPR: pericardial cusps and Dacron conduit, Group PRPR: expanded polytetrafluoroethylene cusps and Dacron conduit). The conduits were designed according to the Ozaki method. Their hydrodynamic performance (effective orifice area, mean pressure gradient and leakage volume) were evaluated in a mock circulation loop at different hydrodynamic conditions.

RESULTS

Hydrodynamic assessment showed significantly larger effective orifice area of PEPE and PEPR compared to PRPR under all conditions and there were no significant differences between PEPE and PEPR [for condition 2: PEPE 2.43 (2.35-2.54) cm2, PEPR: 2.42 (2.4-2.5) cm2, PRPR: 2.08 (1.97-2.21) cm2, adjusted pairwise comparisons: PEPE versus PEPR: P = 0.80, PEPE versus PRPR: P  < 0.001, PEPR versus PRPR: P  < 0.001]. Mean pressure gradient was significantly lower for PEPE and PEPR compared with PRPR, whereas no significant differences were seen between PEPE and PEPR. Leakage volume was significantly lower for PEPE and PEPR compared with PRPR under all conditions while leakage was similar between PEPE and PEPR.

CONCLUSIONS

Pulmonary graft reconstruction with pericardium cusps showed superior hydrodynamic performance compared with polytetrafluoroethylene cusps. Our results suggest that it could be considered as an alternative substitute for right ventricular outflow tract replacement during the Ross procedure.

Dissemination and implementation analysis of the Ross procedure in adults: time to update the guidelines?

Background

The science of dissemination and implementation (D&I) aims to improve the quality and effectiveness of care by addressing the challenges of incorporating research and evidence-based practice into routine clinical practice. This lens of D&I has challenged the interpretation and incorporation of data, noting that failure of a given therapy may not reflect lack of efficacy, but instead reflect an imperfect implementation. The aim of this manuscript is to review the influence of the Ross procedure's historical context on its D&I.

Methods

A contextual baseline of the Ross procedure was defined from the procedure's original description in the literature to major publications since the 2017 valvular heart disease guidelines. D&I evaluation was conducted using the Consolidated Framework for Implementation Research (CFIR), using constructs from each of the five respective domains to define the main determinants.

Results

Each of the five CFIR domains appears to be correlated with a factor influencing the Ross procedure's varied history of enthusiasm and acceptance. The complex nature of Ross required adaptation for optimization, with a strong correlation of center volume on outcomes that were not considered in non-contemporary studies. Outcomes later published from those studies influenced social and cultural contexts within the aortic surgery community, and led to further organizational uncertainty, resulting in slow guideline incorporation.

Conclusions

The D&I of the Ross procedure was a result of inadequate appreciation of technical complexity, effect of patient selection, and complex aortic surgery experience, resulting in dismissal of an efficacious procedure due to a misunderstanding of effectiveness.

Redo aortic root surgery post-Ross procedure

Background

Despite numerous advantages of the Ross procedure, it presents a risk of late autograft and right ventricular outflow tract conduit failure. This study aimed to analyze the outcomes of autograft dysfunction reoperations using autograft-sparing and root replacement techniques.

Methods

Between 2015 and 2023, 49 patients underwent redo root surgery in our institution. Autograft valve-sparing procedures (VSP) were performed in 20 cases and the Bentall procedure (BP) in 29 patients. The short and long-term clinical outcomes along with echocardiographic results of VSP and BP were investigated.

Results

Overall early mortality rate was 2.0% with no significant difference between the groups. Severe autograft valve insufficiency at the time of redo (OR 4.07, P = 0.03) and patient age (OR 1.07, P = 0.04) were associated with a valve replacement procedure instead of VSP. The median follow-up duration was 34 months. No late deaths occurred in either group. Freedom from VSP failure and aortic prosthesis dysfunction were 93.8% and 94.1% in the VSP and BP groups, respectively. No reoperations were necessary in either group.

Conclusion

Redo aortic root surgery can be safely performed in patients with autograft failure. Both root replacement and autograft valve-sparing procedures demonstrated acceptable results at mid-term follow-up. Early redo surgery pre-empting severe aortic insufficiency increases the likelihood of preservation of the dilated autograft valve.

New insights into the hemodynamics of pulmonary homograft patients under stress echocardiography: The contribution of pressure recovery

BACKGROUND

The importance of pulmonary artery pressure recovery (PR) in patients with Ross procedures in whom a homograft substitutes the resected pulmonary valve, is unknown. The aim of the study was to evaluate the occurrence and extent of PR in the pulmonary artery in 65 asymptomatic patients with pulmonary homograft after Ross surgery during rest and exercise.

METHODS

Stress echocardiography was performed in 65 pulmonary homograft patients and 31 controls with native pulmonary valves up to 75 W. Right ventricular systolic pressure (RVSP), transvalvular flow, mean pressure gradient (Pmean ), valve resistance, and RV stroke work were determined in the exercise (max. 75 W) and recovery phases in increments of 25 W each.

RESULTS

Pulmonary homografts demonstrated significantly elevated Pmean compared to controls at all stages. When considering pressure recovery (absolute and relative PR at rest 3.8 ± 1.8 mm Hg, 42.6 ± 7.2%, respectively) and transvalvular energy loss (EL; at rest 4.5 ± 4.3 mm Hg) the homograft hemodynamics reached the level of controls. In a subgroup of patients with tricuspid regurgitation, resting RVSP was the same in homograft patients and controls (21.3 ± 6.1 vs. 20.4 ± 6.3, p = .62), despite significant different Pmax values.

CONCLUSIONS

Ross patients with pulmonary homograft showed systematically increased hemodynamic parameters compared to normal pulmonary valves. These differences were abolished when PR was considered for homograft patients. The equality of RVSP values at rest in both groups shows non-invasive evidence for PR in the pulmonary system after homograft implantation. Therefore, PR appears to be an important measure in calculating the actual hemodynamics in pulmonary homografts.

Autograft reoperations after the Ross procedure

OBJECTIVES

After a Ross procedure, autograft failure can occur. At reoperation, repair of the autograft preserves the advantages of the Ross procedure. The aim of this retrospective study was to assess mid-term results after reoperation of a failed autograft.

METHODS

Between 1997 and 2022, 30 consecutive patients (83% male; age 41 ± 11 years) underwent autograft reintervention between 60 days and 24 years (median 10 years) after a Ross procedure. The initial technique varied, full-root replacement (n = 25) being the most frequent. The indication for reoperation was isolated autograft regurgitation (n = 7), root dilatation (>43 mm) with (n = 17) or without (n = 2) autograft regurgitation, mixed dysfunction (n = 2) and endocarditis (n = 2). In 4 instances, the valve was replaced by valve (n = 1) or combined valve and root replacement (n = 3). Valve-sparing procedures consisted of isolated valve repair (n = 7) or root replacement (n = 19), and tubular aortic replacement. Cusp repair was performed in all but 2. Mean follow-up was 5.4 ± 6 years (35 days to 24 years).

RESULTS

Mean cross-clamp and perfusion times were 74 ± 26 and 132 ± 64 min. There were 2 perioperative deaths (7%; both valve replacement) and 2 patients died late (32 days to 1.2 years postoperatively). Freedom from cardiac death at 10 years was 96% after valve repair and 50% after replacement. Two patients required reoperation (1.68 and 16 years) following repair. One underwent valve replacement for cusp perforation, the other, root remodelling for dilatation. Freedom from autograft reintervention at 15 years was 95%.

CONCLUSIONS

Autograft reoperations after the Ross procedure can be performed as valve-sparing operations in the majority of cases. With valve-sparing, long-term survival and freedom from reoperation are excellent.

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.

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.

Unicuspid Aortic Valve in Patients Undergoing the Ross Procedure

BACKGROUND

The prevalence and outcomes of the unicuspid aortic valve (UAV) in patients undergoing the Ross procedure have been strongly underreported in the current literature. We sought to evaluate this in comparison with bicuspid (BAV) and tricuspid valve (TAV) in our Ross cohort.

METHODS

This was a retrospective observational study of patients undergoing the Ross procedure at 2 dedicated centers between 2009 and 2020. Primary end points were the risks of midterm autograft reoperation and the onset of at least moderate aortic regurgitation during follow-up. The secondary end point was to compare the perioperative outcomes between the groups.

RESULTS

Included in the analysis were 286 patients, of those 39% with UAV, 52% with BAV, and 9% with TAV. UAV patients were operated on at the youngest age (P < .001) and more often for a combined hemodynamic aortic valve pathology (P = .02). They had the largest aortic root dimensions: annulus (P = .01), Valsalva sinuses (P = .11), sinotubular junction (P = .001), and ascending aorta (P < .0001). The risks of reoperation (P = .86) and the onset of aortic regurgitation (P = .75) were comparable among the groups over the follow-up of 4.1 years. There was no difference in perioperative outcomes.

CONCLUSIONS

UAV is a separate unit characterized by a distinct hemodynamic pathology and generated aortopathy. It is not associated with a higher risk of reoperation or new onset of aortic regurgitation after the Ross procedure in the midterm postoperatively. At the current state, UAV remains acceptable for the Ross procedure.

Formal consensus study on surgery to replace the aortic valve in adults aged 18-60 years

OBJECTIVE

There is uncertainty about surgical procedures for adult patients aged 18-60 years undergoing aortic valve replacement (AVR). Options include conventional AVR (mechanical, mAVR; tissue, tAVR), the pulmonary autograft (Ross) and aortic valve neocuspidisation (Ozaki). Transcatheter treatment may be an option for selected patients. We used formal consensus methodology to make recommendations about the suitability of each procedure.

METHODS

A working group, supported by a patient advisory group, developed a list of clinical scenarios across seven domains (anatomy, presentation, cardiac/non-cardiac comorbidities, concurrent treatments, lifestyle, preferences). A consensus group of 12 clinicians rated the appropriateness of each surgical procedure for each scenario on a 9-point Likert scale on two separate occasions (before and after a 1-day meeting).

RESULTS

There was a consensus that each procedure was appropriate (A) or inappropriate (I) for all clinical scenarios as follows: mAVR: total 76% (57% A, 19% I); tAVR: total 68% (68% A, 0% I); Ross: total 66% (39% A, 27% I); Ozaki: total 31% (3% A, 28% I). The remainder of percentages to 100% reflects the degree of uncertainty. There was a consensus that transcatheter aortic valve implantation is appropriate for 5 of 68 (7%) of all clinical scenarios (including frailty, prohibitive surgical risk and very limited life span).

CONCLUSIONS

Evidence-based expert opinion emerging from a formal consensus process indicates that besides conventional AVR options, there is a high degree of certainty about the suitability of the Ross procedure in patients aged 18-60 years. Future clinical guidelines should include the option of the Ross procedure in aortic prosthetic valve selection.

Patients with Bicuspid Aortopathy and Aortic Dilatation

(1) Background: Bicuspid aortic valve (BAV) is the most frequent congenital cardiac disease. Alteration of ascending aorta diameter is a consequence of shear stress alterations due to haemodynamic abnormalities developed from inadequate valve cusp coaptation. (2) Objective: This narrative review aims to discuss anatomical, pathophysiological, genetical, ultrasound, and radiological aspects of BAV disease, focusing on BAV classification related to imaging patterns and flux models involved in the onset and developing vessel dilatation. (3) Methods: A comprehensive search strategy was implemented in PubMed from January to May 2022. English language articles were selected independently by two authors and screened according to the following criteria. (4) Key Contents and Findings: Ultrasound scan is the primary step in the diagnostic flowchart identifying structural and doppler patterns of the valve. Computed tomography determines aortic vessel dimensions according to the anatomo-pathology of the valve. Magnetic resonance identifies hemodynamic alterations. New classifications and surgical indications derive from these diagnostic features. Currently, indications correlate morphological results, dissection risk factors, and genetic alterations. Surgical options vary from aortic valve and aortic vessel substitution to aortic valve repair according to the morphology of the valve. In selected patients, transcatheter aortic valve replacement has an even more impact on the treatment choice. (5) Conclusions: Different imaging approaches are an essential part of BAV diagnosis. Morphological classifications influence the surgical outcome.

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.

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

Background

The Ross procedure is recommended as an optimal aortic valve replacement (AVR) in children and young adults due to several advantages. Nevertheless, multiple reconstructions of the right ventricular outflow tract (RVOT) with new valve conduits have caused some concern regarding the durability of the Ross AVR. Decellularized bovine jugular vein conduit (BJVC) (DP-BJVC) and hand-sewn expanded polytetrafluoroethylene valved conduits (ePTFE VC) are widely employed to reconstruct the RVOT with satisfactory long-term outcomes. However, few studies have compared the safety and efficacy between the two valve conduits. We aimed to evaluate the early outcomes and report our single center experience in the application of these conduits.

Methods

Twenty-two pediatric patients (aged &lt; 18 years) who underwent Ross procedures with DP-BJVC and ePTFE VC in our center between 1 June, 2017 and 31 January, 2022 were enrolled. The Kaplan–Meier method was used to evaluate survival, freedom from RVOT reintervention, and freedom from RVOT graft dysfunction. Mixed-effects analysis with the Geisser–Greenhouse correction and Sidak's multiple comparisons test for post-hoc analysis was employed to compare the peak gradient across the conduit at varying follow-ups.

Results

All patients were followed up in full. The total early survival rate was 90.9%; two patients in the DP-BJVC group died. There was no significant difference in early mortality, cross-clamp time (p = 0.212), in-hospital stay (p = 0.469), and RVOT graft thrombosis or endocarditis between the two groups. There was similarly no significant difference between Kaplan–Meier freedom from RVOT graft dysfunction curve (P = 0.131). The transprosthetic gradient gradually increased over time in both groups and was significantly higher in the DP-BJVC group at follow-up (P &lt; 0.05).

Conclusions

Both conduits show excellent early and midterm outcomes for RVOT reconstruction in the Ross procedure. We suggest that DP-BJVC is more suitable for infants, and ePTFE conduit is more suitable for older children who require larger conduits.

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.

Survival and freedom from reoperation after the Ross procedure in a Russian adult population: A single-center experience

Objectives

To evaluate our 12-year experience with the Ross procedure in adults.

Methods

A retrospective analysis of 215 cases of the Ross procedure was performed. The mean age of the patients was 36 ± 11.1 years, and the male to female ratio was 75% to 25%, respectively. The pulmonary autograft was placed into the aortic position using the full-root replacement technique and its modified versions. The right ventricular outflow tract was reconstructed using a pulmonary homograft in all cases.

Results

The 30-day mortality after the operation was 0.9% (2 patients). The median duration of follow-up was 6.1 years (interquartile range, 6.5 years) and was complete in 86% of cases. The survival at 12 years was 94.7% and was comparable with the survival rate of the general population matched for age and sex. At the end of the follow-up, freedom from reoperation due to pulmonary autograft and homograft dysfunction was 89.1% and 99%, respectively.

Conclusions

In our series, the Ross procedure resulted in low early mortality and excellent survival in adults. The long-term survival was not statistically different from the survival of the general population. The pulmonary homograft offered an excellent durability and freedom from reoperation.

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.

Ross procedure provides survival benefit over mechanical valve in adults: a propensity-matched nationwide analysis

OBJECTIVES

The choice of optimal surgical treatment for young and middle-aged adults with aortic valve disease remains a challenge. Mechanical aortic valve replacement (mAVR) is generally preferred despite promising recent outcomes of the Ross procedure. Our goal was to compare the strategies at a nationwide level.

METHODS

This study was a retrospective analysis of prospectively recorded data from the National Registry of Cardiac Surgery of the Czech Republic. Using propensity score matching, we compared the outcomes of patients undergoing the Ross procedure in 2 dedicated centres with all mAVRs performed in country between 2009 and 2020.

RESULTS

Throughout the study period, 296 adults underwent the Ross procedure and 5120 had an mAVR. We found and compared 291 matched pairs. There were no in-hospital deaths, and the risk of perioperative complications was similar in both groups. Over the average follow-up period of 4.1 vs 6.1 years, the Ross group had a lower all-cause mortality (0.7 vs 6.5%; P = 0.015). This result remained significant even when accounting for cardiac- and valve-related deaths only (P = 0.048). Unlike the Ross group, the mAVR group had a significantly lower relative survival compared with the age- and sex-matched general population. There was no difference in the risk of reoperation (4.5 vs 5.5%; P = 0.66).

CONCLUSIONS

The Ross procedure offers a significant midterm survival benefit over mAVR. The procedures have a comparable risk of perioperative complications. Patients after mAVR have reduced survival. Thus, the Ross procedure should be the preferred treatment option for young and middle-aged adults with aortic valve disease in dedicated centres.

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.

State-of-the-art: Insights from the Ross Registry

The treatment of aortic valve disease in young patients is still a major clinical challenge, as the pre-eminent emphasis is on durability and long-term outcomes beyond 10 to 15 years, sometimes >20 to 30 years. The Ross procedure uses the autologous pulmonary valve as an aortic valve substitute and aims to improve valve durability while avoiding anticoagulation and therefore achieve a sustained long-term result with regard to survival, valve functionality, and quality of life. However, this procedure is technically demanding and only performed at a low frequency. Data investigating the Ross procedure are mostly limited to observational studies from single expert centers, while sufficient randomized data are almost completely lacking. Therefore, to create a clinically relevant database of this therapy, the multicenter Ross Registry was founded in 2001. New patients were included, follow-up of past patients continuously updated, and outcomes regularly reported. Throughout recent years, numerous analyses have been performed to characterize this patient population, surgical techniques, risk factors for morbidity and mortality, and most importantly survival outcomes. Currently, more than 2500 patients are included, and the long-term follow-up has reached >25 years in the very first patients who were included. In the most recent study, 2444 adult patients with a mean age of 44.1 ± 11.7 years were analyzed, and it showed that excellent mid-term survival is maintained after 25 years. In addition, the rate of reintervention was lower than reported in patients with xenografts and anticoagulation-related morbidity lower than reported in patients with mechanical valves. In the absence of robust randomized controlled trials, registry data are very important to monitor outcomes and mirror the quality of current practice. Therefore, the Ross Registry provides a unique and important data base regarding treatment of aortic valve disease in young patients.

Long-term results of modified bentall procedures: 18-year experience of the flanged technique

OBJECTIVES

To evaluate the early and late outcomes of the modified Bentall procedure with the flanged technique.

METHODS

We reviewed the medical records of 63 patients who had undergone root replacement by the modified Bentall procedure at our institute between January 2001 and December 2018. In most cases, we adopted a composite graft constructed with a mechanical valve or bioprosthesis and a Dacron graft by the flanged technique. Since 2011, we have used Valsalva grafts.

RESULTS

Mean age 57 ± 16 years, range 16-80, male 43 cases. The mean follow-up was 75 ± 56 months (range 0-216). Through April 1, 2020, we could follow up on 61 cases (97%) within a six-month period. Hospital mortality was 7.9% (4.8% in elective cases). In late follow-up, eight deaths were observed. In the bio-Bentall group (n=26), no deaths or major adverse valve-related events (MARVEs) occurred. In the mechanical Bentall group (n=37), seven cases of MARVEs, including two cerebral hemorrhages and one cerebral embolism, were observed. All patients were free from MARVEs at 5 years post procedure in the bio-Bentall group, and 93.8% and 76.8% were event-free at 5 years and 10 years, respectively, in the mechanical Bentall group.

CONCLUSIONS

The 18-year results of the modified Bentall procedure were acceptable, providing excellent outcomes in the bio-Bentall group. The flanged technique enabled the use of a larger prosthesis, which may have resulted in good durability with the bio-Bentall procedure.

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.

Ross Operation with Autologous External Autograft Stabilization - Long-term Results

BACKGROUND

We have proposed an external stabilization technique to minimize autograft dilatation after the Ross operation. The aim of this study was to analyze autograft function and root dimensions following root replacement with and without external root support.

METHODS

Between 10/1995 and 02/2021, 185 adult patients (73% male; age 38±9 years) underwent a Ross operation as full-root replacement with (n=136) or without support (n=49). Autograft function and root dimensions were determined echocardiographically. Median follow-up was 3.4[1.13-14.74] years; it was 95% complete. Survival and freedom from reoperation were calculated; changes in autograft root dimensions were analyzed using mixed-effect models.

RESULTS

Survival (95%) and freedom from autograft reoperation (94%) at 15 years were higher with than without support (p=0.003 or p=0.004). In the first five years, patients with support showed an indexed root size progression of 0.712mm/(year*m)(p=0.003) compared to 1.554mm/(year*m)(p=0.001) without. Progression rates were higher for patients without stabilization (p=0.045). After five years, progression rates were similar in both groups (0.248mm/(year*m)(p<0.001) with persistent difference between the groups.

CONCLUSIONS

The Ross procedure as full-root replacement is associated with a relevant rate of autograft dilatation and reoperation. The use of external root stabilization may reduce autograft dilatation and is associated with improved survival and durability.

Wall stresses of early remodeled pulmonary autografts

OBJECTIVE

The Ross procedure is an excellent option for children or young adults who need aortic valve replacement because it can restore survival to that of the normal aged-matched population. However, autograft remodeling can lead to aneurysmal formation and reoperation, and the biomechanics of this process is unknown. This study investigated postoperative autograft remodeling after the Ross procedure by examining patient-specific autograft wall stresses.

METHODS

Patients who have undergone the Ross procedure who had intraoperative pulmonary root and aortic specimens collected were recruited. Patient-specific models (n = 16) were developed using patient-specific material property and their corresponding geometry from cine magnetic resonance imaging at 1-year follow-up. Autograft ± Dacron for aneurysm repair and ascending aortic geometries were reconstructed to develop patient-specific finite element models, which incorporated material properties and wall thickness experimentally measured from biaxial stretching. A multiplicative approach was used to account for prestress geometry from in vivo magnetic resonance imaging. Pressure loading to systemic pressure (120/80) was performed using LS-DYNA software (LSTC Inc, Livermore, Calif).

RESULTS

At systole, first principal stresses were 809 kPa (25%-75% interquartile range, 691-1219 kPa), 567 kPa (485-675 kPa), 637 kPa (555-755 kPa), and 382 kPa (334-413 kPa) at the autograft sinotubular junction, sinuses, annulus, and ascending aorta, respectively. Second principal stresses were 360 kPa (310-426 kPa), 355 kPa (320-394 kPa), 272 kPa (252-319 kPa), and 184 kPa (147-222 kPa) at the autograft sinotubular junction, sinuses, annulus, and ascending aorta, respectively. Mean autograft diameters were 29.9 ± 2.7 mm, 38.3 ± 5.3 mm, and 26.6 ± 4.0 mm at the sinotubular junction, sinuses, and annulus, respectively.

CONCLUSIONS

Peak first principal stresses were mainly located at the sinotubular junction, particularly when Dacron reinforcement was used. Patient-specific simulations lay the foundation for predicting autograft dilatation in the future after understanding biomechanical behavior during long-term follow-up.

Back to the root: a large animal model of the Ross procedure

The excellent clinical outcomes of the Ross procedure and previous histological studies suggest that the pulmonary autograft has the potential to offer young patients a permanent solution to aortic valve disease. We aim to study the early mechanobiological adaptation of the autograft. To this end, we have reviewed relevant existing animal models, including the canine models which enabled Donald N Ross to perform the first Ross procedure in a patient in 1967. Two research groups recently evaluated the isolated effect of systemic pressures on pulmonary arterial tissue in an ovine model of a pulmonary artery interposition graft in the descending aorta. While this model is ideal to study the artery's biological response and the effect of external support, it does not recreate the complex environment of the aortic root. The freestanding Ross procedure has been performed in pigs and sheep before. These studies offered valuable insights into leaflet growth and histological remodeling, yet may be less relevant to adults undergoing the Ross procedure, as pronounced autograft dilatation was achieved by using small, rapidly growing animals. Therefore, a large animal model remains needed to determine the ideal conditions and surgical technique to ensure long-term autograft remodeling and valve function. We set out to develop an ovine model of the Ross procedure performed as a freestanding root replacement, acknowledging that the sheep's specific anatomy and the setting of an animal laboratory would mandate several modifications in surgical strategy. This article describes the development, surgical technique and early outcomes of our animal model while highlighting opportunities for further research.

Systematic review and meta-analysis of long-term outcomes in adults undergoing the Ross procedure

Background

The management of aortic valve disease is becoming increasingly complicated with the evolution of treatment options available to cardiac surgeons and cardiologist. Pulmonary autograft replacement of the aortic valve, commonly known as the Ross procedure, involves excision of the pulmonary valve from the right ventricular outflow tract and implantation in the aortic position. This systematic review aims to evaluate the long-term outcomes, following the Ross procedure.

Methods

An electronic search strategy queried five online medical referencing databases from inception to 21 August 2020. All studies detailing the long-term outcomes of adults undergoing the Ross procedure were included. A random effects model was used to determine pooled continuous data. Enhanced secondary survival analysis was performed on reconstructed individual patient data.

Results

Twenty-three studies were included in the qualitative synthesis, including a total of 6,278 patients with a mean follow-up duration of 6.0±2.8 years. Long-term survival was 95.6%, 91.8%, 86.3% and 80.5% at five, ten, fifteen and twenty years, respectively. Freedom from autograft reoperation was 95.7%, 91.2%, 84.9% and 76.1% at five, ten, fifteen and twenty years, respectively.

Conclusions

When performed in experienced centres and for appropriately selected patients, the Ross procedure represents a durable replacement of the aortic valve with excellent long-term survival.

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.

Ross operation after failure of aortic valve repair

Background

Repair failure remains one of the most important complications of aortic valve reconstruction. Young patients might benefit from a Ross procedure in such a scenario, provided it can be performed safely and with adequate durability. The aim of this study was to assess the safety and clinical outcomes of a Ross operation following a failed repair.

Methods

Between 1996 and 2019, 80 patients (male, 76%; mean age, 31±13 years) underwent a Ross procedure after a median of 6.6 (1.7-15.9) years following an initial aortic valve repair. The previous valve repair was performed for unicuspid (53%), bicuspid (39%), tricuspid (7%), and quadricuspid morphology (1%). Median follow-up after the Ross operation was 2.8 (0.964-13.25) years, mean 5±5 years (92% complete).

Results

Median cardiopulmonary bypass and cross-clamp times were 144 [106-154] minutes and 98 [79-113] minutes, respectively. Thirty-two patients (40%) required a concomitant procedure, most commonly, an ascending aortic replacement (n=23). There were no peri-operative deaths, myocardial infarctions, or neurological complications. There was one late death from a non-cardiac cause. At 10 years, overall survival was 99%±1%, similar to that of an age- and gender-matched population. Nine patients required re-intervention after their Ross procedure (five on the autograft and four on the pulmonary conduit). The autograft re-interventions were valve-sparing procedures in all patients. The cumulative incidence of re-intervention on the autograft at 8 years was 5.1%±3.1%.

Conclusions

The stepwise strategy of an initial valve repair followed by Ross operation represents a safe and valid option for failed aortic valve repair. It is associated with low peri-operative morbidity. Mid-term survival is excellent, similar to that of a matched general population. The probability of re-intervention after the Ross procedure appears similar to that of a primary Ross operation, deeming it a warranted consideration in cases of failed aortic valve repair.

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.

The Ross procedure and valve-sparing root replacement procedures in the adult patient: do guidelines follow the evidence?

Prosthetic aortic valve replacements have long been the mainstay of valvular surgery due to their favorable outcomes and low operative complexity. Yet, mechanical valves require lifelong anticoagulation, whereas bioprosthetic valves increase the risk for earlier and more frequent reoperation. Alternative reconstructive techniques have been proposed to address these challenges. These include valve-sparing root replacement procedures if the native aortic valve can be salvaged, and the Ross procedure, which nearly eliminates prosthetic valve-related thromboembolism, anticoagulation-related hemorrhage and endocarditis. Both procedures are technically more complex and thus subject to surgeons' volume and expertise compared to conventional aortic valve replacements. However, they are associated with more favorable outcomes compared to aortic valve replacements if performed by experienced surgeons, especially in younger patients. Nevertheless, despite the growing high-quality literature supporting both procedures, existing multi-society guidelines fail to acknowledge the strength of evidence in support of valve-sparing root replacement procedures and the Ross procedure. In this review, we summarize the existing long-term evidence for the use of each procedure, describe the current guidelines for the treatment of aortic valve pathology, and propose the reevaluation of guidelines based on the available clinical evidence.

Aortic valve neocuspidization with autologous pericardium in adult patients: UK experience and meta-analytic comparison with other aortic valve substitutes

OBJECTIVES

We sought to provide further evidence on the safety and efficacy of aortic valve neocuspidization (AVNeo) using autologous pericardium in adult patients with aortic valve disease by reporting clinical and echocardiographic results from the first UK experience and performing a meta-analytic comparison with other biological valve substitutes.

METHODS

We reported clinical and echocardiographic outcomes of 55 patients (mean age 58 ± 15 years) undergoing AVNeo with autologous pericardium in 2 UK centres from 2018 to 2020. These results were included in a meta-analytic comparison between series on AVNeo (7 studies, 1205 patients, mean weighted follow-up 3.6 years) versus Trifecta (10 studies, 8705 patients, 3.8 years), Magna Ease (3 studies, 3137 patients, 4.1 years), Freedom Solo (4 studies, 1869 patients, 4.4 years), Freestyle (4 studies, 4307 patients, 7 years), Mitroflow (4 studies, 4760 patients, 4.1 years) and autograft aortic valve (7 papers, 3839 patients, 9.1 years).

RESULTS

In the present series no patients required intraoperative conversion. After mean follow-up of 12.5 ± 0.9 months, 3 patients presented with endocarditis and 1 required reintervention. The remaining patients had absent or mild aortic valve insufficiency with very low peak and mean transvalvular gradients (16 ± 3.7 and 9 ± 2.2 mmHg, respectively). Meta-analytic estimates showed non-significant difference between AVNeo and all but Magna Ease valves with regards to structural valve degeneration, reintervention and endocarditis. When compared Magna Ease valve, AVNeo and other valve substitutes showed an excess of valve-related events.

CONCLUSIONS

AVNeo is safe, associated with excellent haemodynamic profile. Its midterm risk of valve-related events is comparable to most biological valve substitutes. Magna Ease is potentially the best biological choice as far as risk of reintervention is concerned.

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.

Long-term outcomes of the Ross procedure in adults

BACKGROUND

The optimal aortic valve replacement for young and middle-aged adults remains elusive. Although several high-volume international centers and surgeons have demonstrated excellent long-term results with the pulmonary autograft (Ross procedure) in adult patients, current guidelines from the United States do not favor this technique. We evaluated long-term clinical and echocardiographic outcomes of adult patients undergoing the Ross procedure at our center.

METHODS

A retrospective review of 225 consecutive adult patients undergoing the Ross procedure was completed. Kaplan-Meier analysis was performed to evaluate overall survival, which was then compared to an age- and sex-matched general population with the log-rank test. Accounting for death as a competing hazard, the cumulative incidence of reintervention and autograft or homograft dysfunction were estimated over the long-term.

RESULTS

Mean age was 42±11 years, and 62 (28%) patients were at least 50 years old. A bicuspid aortic valve was present in 179 (80%) patients. The most common indications for surgery were aortic insufficiency (n=94, 43%), aortic stenosis (n=81, 36%), and mixed etiology (n=46, 21%). In-hospital mortality was 0.9%. Overall survival (with 95% confidence intervals) at 1-, 10- and 20-year was 97.8% (95.9-99.7%), 94.2% (91.0-97.4%), and 81.3% (74.8-88.3%), respectively. Overall survival approximated that of the general population (log-rank P=0.32). The cumulative incidence (with 95% confidence intervals) of any autograft or homograft reintervention at 10-, 15-, and 20-year was 16% (12-20%), 28% (21-35%), and 45% (36-54%), respectively.

CONCLUSIONS

The Ross procedure restores a normal life expectancy to young and middle-aged adults with severe aortic valve disease. The need for reintervention increases steadily during the second decade after the Ross procedure, but less than half of patients require any reintervention for up to 20-year.

The Ross procedure is a safe and durable option in adults with infective endocarditis: a multicentre study

OBJECTIVES

Surgical treatment of infective endocarditis (IE) remains a challenge. The Ross procedure offers the benefit of a living substitute in the aortic position but it is a more complex operation which may lead to increased operative risk. The aim of this study was to assess the safety and late outcomes of the Ross procedure for the treatment of active IE.

METHODS

From 2000 to 2019, a total of 31 consecutive patients underwent a Ross procedure to treat active IE (mean age 43 ± 12 years, 84% male). All patients were followed up prospectively. Four patients (13%) were intravenous (IV) drug users and 6 patients (19%) had prosthetic IE. The most common infective organism was Streptococcus (58%). Median follow-up was 3.5 (0.9-4.5) years and 100% complete.

RESULTS

There were no in-hospital deaths. One patient suffered a postoperative stroke (3%) and 1 patient (3%) required reintervention for bleeding. Three patients had a new occurrence endocarditis: 2 patients were limited to the pulmonary homograft and successfully managed with IV antibiotics, whereas 1 IV drug user patient developed concomitant autograft and homograft endocarditis. Overall, cumulative incidence of IE recurrence was 13 ± 8% at 8 years. The cumulative incidence for autograft endocarditis was 5 ± 4% at 8 years. Two patients (6%) died during follow-up, both from drug overdoses. At 8 years, actuarial survival was 88 ± 8%.

CONCLUSIONS

In selected patients with IE, the Ross procedure is a safe and reasonable alternative with good mid-term outcomes. Freedom from recurrent infection on the pulmonary autograft is excellent, labelporting the notion that a living valve in the aortic position provides good resistance to infection. Nevertheless, in IV drug user patients, pulmonary homograft endocarditis remains a challenge. Continued follow-up is needed to ascertain the long-term benefits of this approach.

Long-term outcomes after the paediatric Ross and Ross-Konno procedures

OBJECTIVES

The Ross procedure is an attractive option for the management of aortic valve disease in paediatric patients. We reviewed our experience with the paediatric Ross procedure to determine survival and freedom from reoperation in the third decade after surgery.

METHODS

We reviewed the data of 124 paediatric patients [71% male, median age at time of surgery 11.1 years (interquartile range 6-14.8 years); 63.7% bicuspid aortic valve], who underwent the Ross procedure at 2 tertiary centres from April 1991 to April 2020. The Ross-Konno procedures were performed on 14 (11.3%) patients. Deaths were cross-checked with the national health insurance database, and survival status was available for 96.8% of the patients. The median follow-up time was 12.1 years (interquartile range 3-18 years).

RESULTS

There were 3 early and 6 late deaths. All early deaths occurred in patients aged <1 year at the time of surgery. The 25-year survival was 90.3%. Actuarial freedom from reoperation (linearized rates in parentheses) was as follows: Autograft reoperation was 90.8% (0.48%/patient-year) and right ventricular outflow tract (RVOT) reoperation was 67% (2.07%/patient year) at 25 years. The univariable Cox-proportional hazard analysis revealed younger age at time of surgery (P < 0.001), smaller implanted valve size (P < 0.001) and the use of a xenograft rather than a homograft (P < 0.001) as predictors of RVOT reoperation. At multivariable Cox-proportional hazard analysis, only age was an independent risk factor for RVOT reoperation (P = 0.041).

CONCLUSIONS

The Ross and the Ross-Konno procedures are associated with good outcomes in paediatric patients. Reoperation of the RVOT is frequent and associated with younger age.

Long-term Clinical and Echocardiographic Outcomes in Young and Middle-aged Adults Undergoing the Ross Procedure

Importance

There is no ideal valve substitute for young adults requiring aortic valve replacement. Multicenter data supporting use of the Ross procedure with respect to long-term postoperative valve-related mortality and reintervention, as well as function of the autograft and pulmonary homograft, are needed.

Objective

To determine the long-term clinical and echocardiographic outcomes in young and middle-aged patients undergoing the Ross procedure.

Design, Setting, and Participants

A retrospective multicenter international cohort study with a median follow-up period of 9.2 years was conducted in 5 experienced centers regularly performing the Ross procedure. Consecutive patients aged 18 to 65 years were included by each center between 1991 and 2018.

Main Outcomes and Measures

Survival and autograft-related and homograft-related reintervention. Serial echocardiographic measurements of valve function were analyzed using mixed-effects modeling.

Results

During the study period, 1431 patients (74.3% men; n = 1063) were operated on at a median age of 48.5 years (mean [SD], 47.7 [9.5]; range, 18.1-65; interquartile range, 42.7-54.0). Implantation techniques were root inclusion in 355 (24.9%), root replacement in 485 (34.0%), and subcoronary implantation in 587 (41.1%). Right ventricular outflow tract reconstruction was performed with homografts in 98.6% (n = 1189) and bioprostheses in 1.4% (n = 17). Ten patients (0.7%) died before discharge. Median follow-up was 9.2 years (13 015 total patient-years). Survival after 10 and 15 years was 95.1% (95% CI, 93.8%-96.5%) and 88.5% (95% CI, 85.9%-91.1%), respectively. Freedom from autograft and homograft reintervention after 15 years was 92.0% and 97.2%, respectively. Late events were autograft endocarditis in 14 patients (0.11% per patient-year), homograft endocarditis in 11 patients (0.08% per patient-year), and stroke in 37 patients (0.3% per patient-year).

Conclusions and Relevance

Given its excellent short-term and long-term outcome in young and middle-aged adults in this study, the Ross procedure should be considered in young and middle-aged adults who require aortic valve replacement. Patients should be referred to an experienced center with a program dedicated to the Ross procedure.

Current Therapeutic Options in Aortic Stenosis

Aortic stenosis is the most common valvular disease requiring valve replacement. Valve replacement therapies have undergone progressive evolution since the 1960s. Over the last 20 years, transcatheter aortic valve replacement has radically transformed the care of aortic stenosis, such that it is now the treatment of choice for many, particularly elderly, patients. This review provides an overview of the pathophysiology, presentation, diagnosis, indications for intervention, and current therapeutic options for aortic stenosis.

The Choice of Pulmonary Autograft in Aortic Valve Surgery: A State-of-the-Art Primer

The Ross procedure has long been seen as an optimal operation for a select few. The detractors of it highlight the issue of an additional harvesting of the pulmonary artery, subjecting the native PA to systemic pressures and the need for reintervention as reasons to avoid it. However, the PA is a living tissue and capable of adapting and remodeling to growth. We therefore review the current evidence available to discuss the indications, contraindications, harvesting techniques, and modifications in a state-of-the-art narrative review of the PA as an aortic conduit. Due to the lack of substantial well-designed randomized controlled trials (RCTs), we also highlight the areas of need to reiterate the importance of the Ross procedure as part of the surgical armamentarium.

Ross procedure or complex aortic valve repair using pericardium in children: A real dilemma

OBJECTIVE

Difficult to repair aortic valve lesions, requiring the use of a valve substitute, remain controversial in the face of the Ross procedure, despite undeniable technical advances. This study was undertaken to compare midterm outcomes of children treated using the Ross procedure or aortic valvuloplasty for complex aortic valve lesions.

METHODS

Between January 2006 and December 2017, 126 patients aged younger than 18 years were treated for complex aortic stenosis and/or aortic insufficiency and were included in this retrospective study. Only aortic valve lesions requiring repair with an autologous or heterologous pericardial patch were considered complex lesions. Propensity score framework analyses were used to compare outcomes of the Ross and aortic valvuloplasty groups while controlling for confounders.

RESULTS

Among the 126 patients with complex aortic valve lesions, propensity score matching selected 34 unique pairs of patients with similar characteristics. Survival (aortic valvuloplasty, 94.1%; Ross, 91%; P = .89), freedom from overall reintervention (aortic valvuloplasty, 50.1%; Ross, 69%; P = .32), and freedom from infective endocarditis at 8 years (aortic valvuloplasty, 100%; Ross, 85.9%; P = .21) were similar. However, freedom from reintervention in the left ventricular outflow tract at 8 years was lower after aortic valvuloplasty than after the Ross procedure (50.1% vs 100%, respectively; P = .001).

CONCLUSIONS

Aortic valvuloplasty and the Ross procedure yielded similar 8-year outcomes regarding death, reoperation, and infective endocarditis although aortic valvuloplasty tended to be associated with fewer cases of infective endocarditis. Aortic valvuloplasty using a pericardial patch can be chosen as a first-line strategy for treating complex aortic valve lesions and might offer the possibility of a later Ross procedure.

A management framework for left sided endocarditis: a narrative review

Left sided endocarditis (LSE) can include the entirety or portion of mitral and/or aortic valve and the structures in their anatomical contiguity and represent a significant portion of emergency surgical activity. Literature and guidelines on the management of LSE relies mainly on observational studies given the difficulty in designing randomized trials in emergency settings. Heart teams (HT) are often called in to difficult decisions on the most appropriate strategy to adopted in case of LSE. Decision-making should take into account the localization and the extension of the infection, patient preoperative status and comorbidities, presence of a previous valve prosthesis and best timing for surgery. Despite evidence suggests that early surgery may improve survival in patients with complicated infective endocarditis (IE), an increased risk of recurrence and postoperative valvular dysfunctions has been reported. The most important factors associated with long-term outcomes are preoperative multiorgan failure, prosthetic mechanical valve IE, vegetation size ≥15 mm, and timing of surgical treatment. Importantly, up to one third of potential candidates do not undergo surgery and these patients experience extremely high mortality rates. Another important point regards the choice of the optimal valve substitute to be used according to the different clinical situation. The lack of RCT in this field and the difficulty to design this type of studies in the case of non-elective conditions further complicates the possibility to achieve a univocal consensus on the best strategy to be adopted in each form of LSE and further validation studies are needed. On the basis of the current evidences a decisional algorithm is proposed summarizing all the crucial aspects in the management of LSE.

Long-term results after the Ross procedure with the decellularized AutoTissue Matrix P® bioprosthesis used for pulmonary valve replacement

OBJECTIVES

Since 1967, the Ross procedure has been performed to treat aortic valve disease using homografts for pulmonary valve replacement. The decellularized Matrix P® prosthesis was developed to overcome (some) limitations of homografts. Until now, the long-term outcome data have been unavailable.

METHODS

Between 2002 and 2010, the Ross procedures using the Matrix P prosthesis were performed in 492 adult patients (mean age 57.2 ± 10.6 years, range 21-73 years) at our institution. Patient data were prospectively collected and analysed (3617.3 patient-years, mean follow-up 7.7  ±  4.3 years). Completeness of follow-up at 1, 5 and 10 years was 98.4%, 94.5% and 91.0%, respectively.

RESULTS

Hospital mortality was 3.9% (n  = 19). During follow-up, 121 patients died resulting in a survival rate at 5, 10 and 12.5 years of 82.8  ±  1.7%, 70.4  ±  2.3% and 62.4  ±  2.9%, respectively. Echocardiography revealed a high incidence of relevant dysfunction of the Matrix P prosthesis and subsequent right ventricular failure. Primary reoperation/reintervention was necessary for 150 Matrix P and 48 autografts. Freedom from pulmonary valve reoperation at 5, 10 and 12.5 years was 76.2  ±  2.1%, 58.6  ±  2.9% and 53.4  ±  3.4%, respectively. The autograft function and the left ventricular function showed similar results as previously reported with a freedom from autograft reoperation at 5, 10 and 12.5 years of 91.8  ±  1.4%, 86.1  ±  2.0% and 86.1  ±  2.0%, respectively.

CONCLUSIONS

The Matrix P prosthesis used for the right ventricular outflow tract reconstruction in the Ross procedure showed unfavourable long-term echocardiographic results with a high rate of reoperation/reintervention for structural pulmonary valve failure. As a consequence, long-term survival of this patient cohort was impaired. Based on these findings, the use of the Matrix P prosthesis for pulmonary valve replacement for Ross procedures in adults should not be recommended.