The Ross operation: a Trojan horse?†

Lifetime Management of Patients With Severe Aortic Stenosis in the Era of Transcatheter Aortic Valve Replacement

Aortic stenosis is the most common valvular disease. Surgical aortic valve replacement (SAVR) using mechanical valves has been the preferred treatment for younger patients, but bioprosthetic valves are gaining favour to avoid anticoagulation with warfarin. Transcatheter aortic valve replacement (TAVR) was approved in recent years for the treatment of severe aortic stenosis in intermediate- and low-risk patients as an alternative to SAVR. The longer life expectancy of these groups of patients might exceed the durability of the TAVR or SAVR bioprosthetic valves. Therefore, many patients need 2 or even 3 interventions during their lifetime. Because it has important implications on the feasibility of subsequent procedures, the decision between opting for SAVR or TAVR as the primary procedure requires thorough consideration by the heart team, incorporating patient preferences, clinical indicators, and anatomic aspects. If TAVR is favoured initially, selecting the valve type and determining the implantation level should be conducted, aiming for positive outcomes in the index intervention and keeping in mind the potential for subsequent TAVR-in-TAVR procedures. When SAVR is selected as the primary procedure, the operator must make choices regarding the valve type and the potential need for aortic root enlargement, with the intention of facilitating future valve-in-valve interventions. This narrative review examines the existing evidence concerning the lifelong management of severe aortic stenosis, delving into available treatment strategies, particularly emphasising the initial procedure's selection and its impact on subsequent interventions.

Aortic Valve Embryology, Mechanobiology, and Second Messenger Pathways: Implications for Clinical Practice

During the Renaissance, Leonardo Da Vinci was the first person to successfully detail the anatomy of the aortic root and its adjacent structures. Ever since, novel insights into morphology, function, and their interplay have accumulated, resulting in advanced knowledge on the complex functional characteristics of the aortic valve (AV) and root. This has shifted our vision from the AV as being a static structure towards that of a dynamic interconnected apparatus within the aortic root as a functional unit, exhibiting a complex interplay with adjacent structures via both humoral and mechanical stimuli. This paradigm shift has stimulated surgical treatment strategies of valvular disease that seek to recapitulate healthy AV function, whereby AV disease can no longer be seen as an isolated morphological pathology which needs to be replaced. As prostheses still cannot reproduce the complexity of human nature, treatment of diseased AVs, whether stenotic or insufficient, has tremendously evolved, with a similar shift towards treatments options that are more hemodynamically centered, such as the Ross procedure and valve-conserving surgery. Native AV and root components allow for an efficient Venturi effect over the valve to allow for optimal opening during the cardiac cycle, while also alleviating the left ventricle. Next to that, several receptors are present on native AV leaflets, enabling messenger pathways based on their interaction with blood and other shear-stress-related stimuli. Many of these physiological and hemodynamical processes are under-acknowledged but may hold important clues for innovative treatment strategies, or as potential novel targets for therapeutic agents that halt or reverse the process of valve degeneration. A structured overview of these pathways and their implications for cardiothoracic surgeons and cardiologists is lacking. As such, we provide an overview on embryology, hemodynamics, and messenger pathways of the healthy and diseased AV and its implications for clinical practice, by relating this knowledge to current treatment alternatives and clinical decision making.

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.

Ross procedure versus pulmonary homograft versus mechanical valve versus bioprosthetic valve versus Ozaki procedure for surgical aortic valve replacement: a frequentist network meta-analysis

BACKGROUND

There has been a resurgence in interest regarding the Ross procedure due to recent publications detailing positive long-term outcomes. Conversely, surgical aortic valve replacement (SAVR) with a pulmonary homograft (PH), mechanical (MV), bioprosthetic (BV), or the Ozaki procedure each has its own technical advantages and disadvantages. Therefore, we performed a network meta-analysis (NMA) comparing other alternatives to Ross procedure.

METHODS

Medical databases were comprehensively searched for studies comparing the Ross procedure with AVR using a PH, MV, BV, or the Ozaki procedure. Outcomes were pooled as risk ratios (RR) with their 95% confidence intervals (95% CI).

RESULTS

A total of 7816 patients were pooled for our NMA from 24 studies. Compared to Ross procedure, both BV and MV were associated with significantly higher rates of 30-day mortality of RR (2.37, 95% CI 1.20-4.67) and (1.88 95% CI 1.04-3.40), respectively, with no significant difference regarding PH or Ozaki. However, only MV was associated with a higher risk of 30-day stroke (RR 8.42, 95% CI 1.57-45.23) with no significant difference in the other alternatives, as well as 30-day MI which showed no significant differences between any of the aortic conduits compared to the Ross procedure. Regarding 30-day major bleeding, MV was associated with a higher when compared to the Ross procedure RR (4.58, 95% CI 1.94-10.85), PH was associated with a lower risk of major bleeding with RR (0.35, 95% CI 0.17-0.71), and BV showed no significant difference. With a mean follow-up duration of 8.5 years compared to the Ross procedure, BV, PH, and MV were associated with a higher risk of long-term mortality with RR (1.89, 95% CI 1.38-2.58), (1.38, 95% CI 1.0-1.87), and (1.94, 95% CI 1.52-2.47), respectively, with the Ozaki procedure showed no significant difference. Regarding long-term stroke-with a mean of 6.3-year follow-up duration-there were no significant differences between any of the aortic conduits compared to the Ross procedure. Nevertheless, long-term need for reintervention-with a mean follow-up duration of 17.5 years-was significant of higher risk with both BV and PH with RR (3.28, 95% CI 1.21-8.84) and (2.42, 95% CI 1.05-5.58), respectively, compared to Ross procedure with MV and Ozaki having no significant difference.

CONCLUSIONS

The Ross procedure is a viable treatment option for patients undergoing SAVR, showing promising outcomes at short- and long-term follow-ups.

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.

Outcomes of Redo Operations after Ross procedure

BACKGROUND

The Ross procedure is not commonly performed, owing to the procedural complexity and the risk of autograft and/or homograft reoperation. This study examined outcomes of patients undergoing Ross reinterventions at a dedicated Ross center.

METHODS

We retrospectively reviewed 225 consecutive patients who underwent a Ross procedure between 1994 and 2019. Index and redo operation characteristics and outcomes were compared between patients with and those without redo operations. Multivariate analysis was used to identify independent predictors of Ross-related reinterventions. Survival was estimated with Kaplan-Meier analysis.

RESULTS

Sixty-six patients (29.3%) required redo Ross surgery, 41 patients (18.2%) underwent autograft reoperation only, 8 patients (3.6%) had a homograft reintervention, and 17 patients (7.6%) had both autograft and homograft reoperations (12 as a combined procedure and 5 as sequential procedures). The mean time to reintervention was 11 ± 6 years for autograft reoperations and 12 ± 7 years for homograft reoperations. Patients who underwent Ross-related reinterventions were younger (mean, 38 ± 11 years vs 43 ± 11 years; P < .01) and had a higher rate of New York Heart Association class III/IV (56% vs 38%; P = .02) at the index Ross procedure. Most patients undergoing autograft reintervention had aortic insufficiency and/or aneurysm (98.2%; 57 of 58). The primary reason for homograft reintervention was pulmonary stenosis (92%; 23 of 25). The operative mortality of Ross reintervention was 1.5% (1 of 66). Survival at 15 years was similar in patients who required a redo operation and those who did not (91.2% vs 93.9%; P = .23).

CONCLUSIONS

Ross reinterventions can be performed safely and maintain patients at the normal life expectancy restored by the index Ross procedure up to 15 years at experienced centers.

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.

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.

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.

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 reinforced full-root technique for the Ross operation: surgical considerations and operative insights

Background

Surgical treatment of young and middle-aged patients suffering from aortic valve disease remains an unresolved issue due to the limited durability of bioprosthetic heart valve replacements and the valve-related morbidity of patients with mechanical valve substitutes. Theoretically, the "living valve" principle of the Ross operation may represent a potentially viable solution to this dilemma. In this paper, we report on the surgical techniques of the Ross procedure and present long-term post-operative outcomes using the reinforced full-root technique.

Methods

From 1995 to 2020, a total of 832 consecutive patients (mean age, 43.4±13.7 years; 617 males) underwent a Ross operation using the full-root technique. Patients were prospectively monitored with clinical and echocardiographic follow-up. Total follow-up was 9,046 patients-years and was 92% complete. Mean-follow-up was 10.9±6.9 years (range, 0-24.9 years).

Results

Survival at twenty years was 92% (95% CI: 90-94%). Freedom from autograft or right ventricle to pulmonary artery connection reoperation at twenty years was 79% (95% CI: 74-85%). Eighty-nine pulmonary autograft reoperations had to be performed in eighty patients; salvage of the pulmonary autograft could be performed in forty-six of them. Fifty-seven patients required sixty-three reoperations on the right ventricle to pulmonary artery connection. Major cerebral bleeding occurred in one patient and neurological events in seventeen patients, respectively.

Conclusions

Over a follow-up interval of up to twenty-five years, the Ross operation with the reinforced full-root technique demonstrated excellent survival in young and middle-aged patients. The rate of pulmonary autograft and right ventricular outflow graft reoperations were low in this patient subset. Therefore, the Ross operation with the reinforced full-root technique represents an enduring and valid treatment option in young and middle-aged patients suffering from aortic valve disease.

Severe degeneration of a sub-coronary pulmonary autograft in a young adult

Background. The pulmonary autograft is currently the best valve substitute in terms of longevity and performance. However, there is no agreement about the optimal method of insertion (sub-coronary position or freestanding root). Objectives. We sought to examine the clinical status, detailed imaging and morphometric changes in an explanted pulmonary autograft 22 years after sub-coronary implantation. Methods. A 30-year-old female underwent pulmonary autograft replacement of a severely stenotic valve at the age of 7 years, after presenting to us with signs of moderate to severe heart failure. She underwent clinical examination, detailed imaging including echocardiographic and CT examination with computerised image analysis. The explanted valve was examined by morphometry. Results. Clinical examination showed signs of heart failure (NYHA III). Trans-thoracic and trans-oesophageal 2D echo showed severe malfunction of both the aortic and pulmonary valves associated with dilatation and hypertrophy of both the right and left ventricles. Surgical correction was performed by replacing both the pulmonary and aortic valves with Medtronic 27mm Freestyle valves. The pulmonary autograft showed degeneration of the trilamellar layering of the leaflets, loss and disorganisation of GAGs, increased collagen with fibrotic overgrowth, and markers of fibrosis, inflammation, and calcification. Post-operative imaging showed good correction of the haemodynamic lesions. Conclusion. The pulmonary autograft implanted into the sub-coronary position presented with adverse remodelling, which was detrimental to the functionality and longevity of the valve. Authorship. NL, AM, MN all contributed equally to this paper.

Considerations in the Surgical Management of Unicuspid Aortic Stenosis

Unicuspid aortic valve (UAV) stenosis is a rare condition accounting for 5% of non-rheumatic aortic stenosis. The diagnosis can be difficult to make prior to surgical intervention and transesophageal echocardiography has been demonstrated to be more accurate in making the diagnosis compared to transthoracic echocardiography. The presence of a posteriorly located aortic orifice on the short-axis views, with one or two visible raphe anteriorly; the absence of commissures (acommissural); or the presence of a lone commissure (unicommissural) between the left and noncoronary, or the left and right cusps suggests the diagnosis. Patients with UAV are predominantly males and present with stenosis about a decade earlier than those with the more prevalent bicuspid aortic valves (BAV). They more commonly present with aortic annular dilatation and have fewer comorbidities at presentation compared to patients with BAV. Surgical management of UAV stenosis includes aortic valve replacement through standard open heart surgery or percutaneous transcatheter aortic valve replacement (TAVR), aortic valve repair either by bicuspidization, tricuspidization or trileaflet reconstruction, or the Ross procedure. Patients with UAV stenosis require less concomitant coronary or other cardiac procedures when they need surgical intervention, but are about a decade younger at the time of their death. UAV stenosis is a distinct congenital anomaly with a different natural course than BAV. Surgical management should be individualized based on the patient's age at presentation, aortoannular anatomy, and associated cardiac conditions.

Contemporary Ross procedure outcomes: medium- to long-term results in 214 patients

OBJECTIVE

Our goal was to present 2 decades of our experience with the Ross procedure and its sequential modifications, adopted since 2010, to improve the reoperation rate.

METHODS

We performed a single-centre, retrospective review of database information and medical notes about the implantation technique: the freestanding root. We compared era 1 (1997-2009) and era 2 (2010-2019).

RESULTS

Between 1997 and 2019, a total of 214 Ross procedures were performed (71% men, median age 24 years) [interquartile range (IQR) 15-38]. Of these, 87% had various forms of congenital-dysplastic aortic valves. The median cross-clamping and bypass times were 173 (IQR 148-202) and 202 (IQR 182-244) min. The median postoperative stay was 6 days (2-77). Thirty-day mortality was 0.5%. The median follow-up time was 8.2 years (IQR 3.9-13.2). Survival at 10 and 20 years was 97% and 95%; freedom from greater than moderate aortic regurgitation or aortic valve intervention was 91% and 80%; and 93% of the patients were in New York Heart Association functional class I. Twenty (21%) patients operated on during era 1 and 6 (9%) during era 2 underwent autograft reoperations. The median follow-up time was 14.3 (IQR 11.5-17.4) and 4.8 (IQR 2.5-7) years. Freedom from autograft reoperation was 87% and 69% at 10 and 20 years, with no significant difference between eras. Freedom from homograft reoperation was 96% and 76% at 10 and 20 years. The presence of aortic regurgitation, infective endocarditis and era 1 were predictors of autograft reoperation. Male gender and era 1 were predictors of neoaortic root dilatation.

CONCLUSIONS

The contemporary modified Ross procedure continues to deliver excellent results and should remain part of the strategy to treat children and young adults requiring aortic valve replacement.

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.

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.

Revisiting the guidelines and choice the ideal substitute for aortic valve endocarditis

Aortic valve replacement is the most commonly performed cardiac surgical operation worldwide for infective endocarditis (IE). Long-term durability and avoidance of infection relapse are the treatment goals. However, no detailed guidelines on prosthesis selection and surgical strategy are available. Management should be guided by a comprehensive evaluation of infection extension and its microbiological characteristics, the clinical profile of the patient and the risk of infection recurrence. We conducted a literature search of the PubMed database, EMBASE and Cochrane Library (through November 2019) for studies reporting to the use of biological substitutes in aortic valve endocarditis (AVE). Studies comparing long-term outcomes in the use of allogenic and autologous with conventional prostheses were investigated. Conventional mechanical or stented xenografts are the preferred choice for localized aortic infection. In cases of complex IE with the involvement of the root or the aorto-mitral continuity, the use of homografts are recommended, according to surgeon's and center experience. Homograft use needs to be balanced against the risk of structural degeneration. Prosthetic bioroot or prosthetic valved conduit with a mechanical or bioprosthetic valve are acceptable alternatives. The choice of aortic valves substitute and surgical strategy in IE is multifaceted. Principles guiding the selection of prosthesis and surgical approach rely on the long-term durability and the avoidance of infection relapse. A decisional algorithm considering the extension of the infection and its microbiological characteristics, the clinical profile of the patient and the risk of infection recurrence is provided. A multidisciplinary effort is required to achieve consistent outcomes.

Ross Procedure vs Mechanical Aortic Valve Replacement in Adults: A Systematic Review and Meta-analysis

Importance

The ideal aortic valve substitute in young and middle-aged adults remains unknown.

Objective

To compare long-term outcomes between the Ross procedure and mechanical aortic valve replacement in adults.

Data Sources

The Ovid versions of MEDLINE and EMBASE classic (January 1, 1967, to April 26, 2018; search performed on April 27, 2018) were screened for relevant studies using the following text word search in the title or abstract: ("Ross" OR "autograft") AND ("aortic" OR "mechanical").

Study Selection

All randomized clinical trials and observational studies comparing the Ross procedure to the use of mechanical prostheses in adults undergoing aortic valve replacement were included. Studies were included if they reported any of the prespecified primary or secondary outcomes. Studies were excluded if no clinical outcomes were reported or if data were published only as an abstract. Citations were screened in duplicate by 2 of the authors, and disagreements regarding inclusion were reconciled via consensus.

Data Extraction and Synthesis

This meta-analysis was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology guidelines. Data were independently abstracted by 3 reviewers and pooled using a random-effects model.

Main Outcomes and Measures

The prespecified primary outcome was all-cause mortality.

Results

The search identified 2919 reports, of which 18 studies (3516 patients) met inclusion criteria, including 1 randomized clinical trial and 17 observational studies, with a median average follow-up of 5.8 (interquartile range, 3.4-9.2) years. Analysis of the primary outcome showed a 46% lower all-cause mortality in patients undergoing the Ross procedure compared with mechanical aortic valve replacement (incidence rate ratio [IRR], 0.54; 95% CI, 0.35-0.82; P = .004; I2 = 28%). The Ross procedure was also associated with lower rates of stroke (IRR, 0.26; 95% CI, 0.09-0.80; P = .02; I2 = 8%) and major bleeding (IRR, 0.17; 95% CI, 0.07-0.40; P < .001; I2 = 0%) but higher rates of reintervention (IRR, 1.76; 95% CI, 1.16-2.65; P = .007; I2 = 0%).

Conclusions and Relevance

Data from primarily observational studies suggest that the Ross procedure is associated with lower all-cause mortality compared with mechanical aortic valve replacement. These findings highlight the need for a large, prospective randomized clinical trial comparing long-term outcomes between these 2 interventions.

The use of allogenic and autologous tissue to treat aortic valve endocarditis

The surgical treatment of aortic valve endocarditis (AVE) is generally performed using conventional mechanical or biological xenograft prosthesis, with limited use of aortic homograft (Ao-Homo) or pulmonary autograft (PA). Clinical evidence has demonstrated a clear contradiction between the proven benefits of Ao-Homo and PA in the context of infection and the very limited use of allogenic or autologous tissue in everyday clinical practice. This review aims to summarize the most recent and relevant literature in order to foster the scientific debate on the use of the use of allogenic and autologous tissue to treat AVE. The decisional process of the Heart Team should also include the preferences of the patient, his/her family, the general cardiologist or primary care physician. The use of allogenic or autologous valve substitute is beneficial if there is a high risk of recurrence of infection, avoiding extensive adhesiolysis and debridement of synthetic material. In any case, those procedures should be performed by highly trained centers to optimize outcomes.

Aortic Valve Surgery in Nonelderly Patients: Insights Gained From AVIATOR

Aortic valve surgery in non-elderly patients represents a very challenging patient population. The younger the patient is at the point of aortic valve intervention, the longer their anticipated life expectancy will be, with longer exposure to valve-related complications and risk for re-operation. Although the latest international guidelines recommend aortic valve repair in patients with aortic valve insufficiency, what we see in the real world is that the vast majority of these aortic valves are replaced. However, current prosthetic valves has now been shown to lead to significant loss of life expectancy for non-elderly patients up to 50% for patients in their 40s undergoing mechanical aortic valve replacement. Bioprostheses carry an even worse long-term survival, with higher rates of re-intervention. The promise of trans-catheter valve-in-valve technology is accentuating the trend of bioprosthetic implantation in younger patients, without yet the appropriate evidence. In contrast, aortic valve repair has shown excellent outcomes in terms of quality of life, freedom from re-operation and freedom from major adverse valve-related events with similar life expectancy to general population as it is also found for the Ross procedure, the only available living valve substitute. We are at a time when the paradigm of aortic valve surgery needs to change for the better. To better serve our patients, we must acquire high quality real-world evidence from multiple centers globally - this is the vision of the AVIATOR registry and our common responsibility.

Expanding Eligibility for the Ross Procedure: A Reasonable Proposition?

BACKGROUND

Although the Ross procedure offers potential benefits in young adults, technical complexity represents a significant limitation. Therefore, the safety of expanding its use in more complex settings is uncertain. The aim of this study was to compare early outcomes of standard isolated Ross procedures vs expanding elgibility to higher-risk clinical settings.

METHODS

From 2011 to 2016, 261 patients (46 ± 12 years) underwent Ross procedures in 2 centres. Patients were divided into 2 groups: standard Ross (n = 166) and expanded eligibility Ross (n = 95). Inclusion criteria for the expanded eligibility group were previous cardiac surgery, acute aortic valve endocarditis, severely impaired left ventricular (LV) function and patients undergoing concomitant procedures. All data were prospectively collected and are 100% complete.

RESULTS

Hospital mortality was 0% in the standard group (0/166) vs 2% in the expanded eligibility group (2/95) (P = 0.13). Sixteen patients (10%) developed acute renal injury in the standard group vs 13 (14%) patients in the expanded eligibility group (P = 0.31). There were no postoperative myocardial infarctions, no neurological events, and no infectious complications. Median intensive care unit (ICU) stay in the standard group was 2 vs 3 days in the expanded eligibility group (P = 0.004), whereas median hospital stay was 6 vs 7 days, respectively (range: 3-19 days) (P < 0.001).

CONCLUSION

Aside from longer ICU and hospital lengths of stay after the Ross procedure in higher-risk clinical scenarios, perioperative mortality and morbidity is similar to standard Ross procedures. Expanding the use of the Ross operation in young adults is a safe alternative in centres of expertise.

Repair of a Quadricuspid Autograft

Aortic valve replacement using a pulmonary autograft is an accepted option in children and young patients. The use of a pulmonary valve with congenital anomaly as autograft is controversial. We describe a case in which a quadricuspid pulmonary valve was used as an autograft in childhood. The patient presented with severe regurgitation 13 years later. Repair was performed with stabilization of the root and cusp prolapse correction, leading to normalized valve function. Despite concerns over the long-term durability of an anomalous pulmonary valve as autograft, good mid to long-term results can be achieved.

Long-Term Clinical and Imaging Follow-Up After Reinforced Pulmonary Autograft Ross Procedure

The Ross operation remains a controversially discussed procedure when performed in the full root technique because concern exists regarding late dilatation of the pulmonary autograft and regurgitation of the neo-aortic valve. In 2008, we published our short-term experience when using external reinforcement of the autograft, which was inserted into a prosthetic Dacron graft. This detail was thought to prevent neoaortic root dilatation. Since 2006, 22 adult patients have undergone a Ross procedure using this technique. Indications were aortic regurgitation (n = 2), aortic stenosis (n = 15), and combined aortic stenosis and insufficiency (n = 5). A bicuspid aortic valve was present in 10 patients. Prior balloon valvuloplasty had been performed in seven patients. No early or late deaths occurred in this small series. One patient required aortic valve replacement early postoperatively, but freedom from late reoperation is 100% in the 21 remaining patients. Echocardiography confirmed the absence of more than trivial aortic insufficiency in 15 patients after a mean of 70 months (range, 14 to 108 months). No autograft dilatation was observed during follow-up and all patients are in New York Heart Association Class I. Autograft reinforcement is a simple and reproducible technical adjunct that may be especially useful in situations known for late autograft dilatation, namely, bicuspid aortic valve, predominant aortic insufficiency, and ascending aortic enlargement. The mid- to long-term results are encouraging because no late aortic root enlargement has been observed and the autograft valve is well functioning in all cases.

Long-Term Outcomes of the Ross Procedure Versus Mechanical Aortic Valve Replacement: Propensity-Matched Cohort Study

BACKGROUND

The ideal aortic valve substitute in young and middle-aged adults remains unknown. We sought to compare the long-term outcomes of patients undergoing the Ross procedure and those receiving a mechanical aortic valve replacement (AVR).

METHODS

From 1990 to 2014, 258 patients underwent a Ross procedure and 1444 had a mechanical AVR at a single institution. Patients were matched into 208 pairs through the use of a propensity score. Mean age was 37.2±10.2 years, and 63% were male. Mean follow-up was 14.2±6.5 years.

RESULTS

Overall survival was equivalent (Ross versus AVR: hazard ratio, 0.91, 95% confidence interval, 0.38-2.16; P=0.83), although freedom from cardiac- and valve-related mortality was improved in the Ross group (Ross versus AVR: hazard ratio, 0.22; 95% confidence interval, 0.034-0.86; P=0.03). Freedom from reintervention was equivalent after both procedures (Ross versus AVR: hazard ratio, 1.86; 95% confidence interval, 0.76-4.94; P=0.18). Long-term freedom from stroke or major bleeding was superior after the Ross procedure (Ross versus AVR: hazard ratio, 0.09; 95% confidence interval, 0.02-0.31; P<0.001).

CONCLUSIONS

Long-term survival and freedom from reintervention were comparable between the Ross procedure and mechanical AVR. However, the Ross procedure was associated with improved freedom from cardiac- and valve-related mortality and a significant reduction in the incidence of stroke and major bleeding. In specialized centers, the Ross procedure represents an excellent option and should be considered for young and middle-aged adults undergoing AVR.

Special report: 26-year durability of a bioprosthesis implanted in a 21-year-old patient

The choice of prosthetic heart valve type is largely dependent upon patient's age at implantation and on what, in his eyes, seems more pertinent: avoidance of complications associated with anticoagulation of mechanical valves or structural valve deterioration of bioprosthetic valves. Long lasting and new promising concepts such as transcatheter aortic valve implantation are promoting the use of bioprosthesis even in younger patients. However, it is up to the individual patient to decide.

The Ross procedure using autologous support of the pulmonary autograft: techniques and late results

OBJECTIVES

It is hypothesized that by performing radical aortic root manipulation and then autologous support for the pulmonary autograft in the Ross procedure, this will maintain aortic root size and should, in turn, lead to the demonstrated low incidence of late aortic regurgitation and need for reoperation on the aortic root and valve.

METHODS

Aortic root size was measured echocardiographically both preoperatively and then at second yearly intervals in 322 consecutive patients who underwent a Ross operation between October 1992 and June 2013 with autologous support of the pulmonary autograft root using the patient's own aorta. This technique, a variant of the inclusion cylinder method, has been developed with the aim of minimizing prosthetic materials in the aortic root.

RESULTS

Measures to reduce aortic root size included annulus reduction in 201 patients (62.4%) and reduction in aortic sinus or sinotubular junction in 159 patients (49.4%). Maximal aortic root diameter postoperatively at 5, 10, and 15 years was 34.0, 34.6, and 34.7 mm, respectively. Eleven reoperations were required during the study period for progressive aortic regurgitation (none for aortic root enlargement), with freedom from reoperation being 96% at both 15 years and 18 years. Preoperative pure aortic regurgitation, aortic annulus, and sinotubular junction enlargement were risk factors for reoperation.

CONCLUSIONS

This inclusion method of pulmonary autograft implantation leads to minimal increases in aortic root size over time, with no reoperations for aortic root dilatation and a low requirement for aortic valve reoperation. The Ross procedure deserves to remain on the surgical menu for aortic valve replacement.

Long-term results of the Ross operation: an 18-year single institutional experience

OBJECTIVES

The purpose of the study was to assess the 18-year outcome of the Ross operation (RO), with emphasis on survival, reoperations, and late function of the pulmonary autografts (PAs) and the right-sided pulmonary allografts.

METHODS

Between May 1995 to July 2013, 414 patients with a mean age (mean ± standard deviation) of 30.8 ± 13.1 years were submitted to an RO with the root replacement (n = 356) or the inclusion (n = 58) technique. The most prevalent aetiology was bicuspid valve (n = 206, 49.8%). Patients were divided in four groups depending on the type of allograft used on the right side. The mean follow-up was 8.2 ± 5.2 years and was 97.7% complete. In addition to longitudinal outcomes determined by means of the Kaplan-Meier analysis, log-rank test and Cox regression analysis were used to identify predictors of valve failure.

RESULTS

The early mortality rate was 2.7% and the late survival rate was 89.3% at 15 years, similar to an age- and sex-matched population. There were 22 reoperations on the PA (90.7% freedom at 15 years) and 15 on the pulmonary allografts (92.5% freedom at 15 years). The freedom rate from more than mild aortic insufficiency (AI) was 73.1% at 15 years. Thirty-three patients presented with a late root diameter >45 mm, corresponding to a freedom rate of 72.4% at 15 years. Patients with AI and a dilated annulus, especially males, are at greater risk for these complications. Among the right-sided allografts, fresh decellularized allografts showed significantly superior freedom from structural valve dysfunction.

CONCLUSIONS

The RO was associated with excellent long-term survival and low incidence of reoperations up to 15 years. Male patients with AI and dilated annulus are at increased risk for late insufficiency and root dilatation. Fresh decellularized allografts presented the best results for reconstruction of the right ventricular outflow tract.