Neoaortic Valve and Root Complex Evolution After Ross Operation in Infants, Children, and Adolescents

Long-term autograft dilation and durability after the Ross procedure are similar in infants, children, and adolescents with primary aortic stenosis

BACKGROUND

Autograft durability and remodeling are thought to be superior in younger pediatric patients after the Ross operation. We sought to delineate the fate of autografts across the pediatric age spectrum in patients with primary aortic stenosis (AS).

METHODS

We retrospectively reviewed patients age ≤18 years with primary AS who underwent the Ross operation between 1993 and 2020. Patients were categorized by age. The primary endpoint was autograft dimensional change, and secondary endpoints were severe neo-aortic insufficiency (AI) and autograft reintervention.

RESULTS

A total of 119 patients underwent the Ross operation, including 37 (31.1%) in group I (age <18 months), 24 (20.2%) in group II (age 18 months-8 years), and 58 (48.7%) in group III (age 8-18 years). All groups exhibited similar annular growth rates within the first 5 postoperative years, followed by a collective decrease in annulus growth rates from year 5 to year 10. Group III experienced rapid sinus dilation in the first 5 years, followed by stabilization of the sinus z-score from year 5 to year 10, whereas groups I and II demonstrated stable sinus z-scores over 10 years. There were 4 early deaths (3.4%) and 2 late deaths (1.7%) at a median follow-up of 8.1 years (range, 0.01-26.3 years). At 15 years, the incidences of severe neo-AI (0.0 ± 0.0% vs 0.0 ± 0.0% vs 3.9 ± 3.9%; P = .52) and autograft reintervention (8.4 ± 6.0% vs 0.0 ± 0.0% vs 2.4 ± 2.4%; P = .47) were similar in the 3 groups.

CONCLUSIONS

Age at the time of Ross operation for primary AS does not influence long-term autograft remodeling or durability. Other physiologic or technical factors are likely greater determinants of autograft fate.

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

AIMS

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

METHODS AND RESULTS

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

CONCLUSION

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

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.

Ross Operation in Pediatric Population: Impact of the Surgical Timing and the Native Pulmonary Diameter on the Outcome

Aortic valve replacement early in life may be inevitable. Ross operation, until present day, remains the favorite surgical option in pediatrics with irreparable aortic valve disease. Nonetheless, the necessity for re-operation was always its principal limitation due to aortic valve failure or homograft degeneration. We present our 25 years of experience in the pediatric population. From August 1994 until June 2018, 157 children below 18 years underwent the Ross operation. This retrospective review aims at assessing the long-term outcomes, as well as the risk factors for re-operation after Ross procedure. Median age was 10.9 years, of which seven patients were infants, 79 children, and 71 adolescents. The median follow-up time was 14 years. Hospital mortality was 0.6%. Freedom from autograft re-operation for children was 96.7% and 94.1% at 10 and 20 years, respectively; whereas for adolescents, it was 92.6% and 74.9% at 10 and 20 years. For children, freedom from homograft re-operation was 92.5%, 83.5%, and 56.2% at 10, 15, and 20 years; while for adolescents, it was 96.8%, 91.8%, and 86.7% at 10, 15, and 20 years. Homograft size (p = 0.008) and childhood (p = 0.05) were risk factors for homograft re-operation. Pulmonary valve diameter > 24 mm (p = 0.044) and adolescence (p = 0.032) were risk factors for autograft re-operation. Our experience demonstrated excellent early and late survival. While children have preferential outcomes concerning autograft re-operation, those who received a smaller homograft had a higher right-sided re-intervention incidence than adolescents. Pulmonary diameter > 24 mm at surgery was an indicator of future autograft failure.

Eversion for Stabilization: A Standardized Technique for Pulmonary Autograft Inclusion

We have developed a new technique avoiding autograft distortion and narrowing at inclusion during Ross procedure, in order to preserve the functional anatomy and the process of adaptation.

Outcomes and Quality of Life After Ross Reintervention: Would You Make the Same Choice Again?

BACKGROUND

The Ross procedure was introduced as a long-term if not definitive solution for aortic pathology. However, the rate of reoperation is not negligible.

METHODS

This single-center prospective study assessed the general outcome of Ross reoperation and patients' perceived quality of life compared with 2 control groups (Ross non-reoperation and mechanical aortic valve replacement). Patient's preference regarding the choice between mechanical aortic valve and Ross procedure was investigated in a subgroup that could theoretically have been directed to either of the 2 procedures.

RESULTS

Between 2005 and 2017, 64 consecutive patients underwent reoperation after Ross. Median age was 31 years. Median freedom from reoperation after the Ross procedure was 136 months. An autograft reoperation was required in 49, and 25 had homograft failure. No in-hospital death was recorded. Mean follow-up was 77 months (range, 6-164 months). Quality of life was assessed with the 36-Item Short Form Health Survey questionnaire. The Ross reoperation group showed a lower score involving psychological concerns compared with the other groups. In the reoperated-on patients group, 52 had adequate aortic annulus dimensions to receive a prosthetic valve instead of a Ross procedure. When asked whether they would make the same choice, only 31% confirmed the preference.

CONCLUSIONS

Reoperations after Ross procedure have low mortality and morbidity. Long-term follow-up showed a high quality of life, even after reoperations. However, owing to psychological concerns after the redo operation, when choosing a Ross procedure, it is our duty to thoroughly explain to patients that a high level of disillusion is predictable in case of reoperations.

Neo-aortic insufficiency late after staged reconstruction for hypoplastic left heart syndrome: impact of differences in initial palliative procedures

The neo-aortic insufficiency in patients with hypoplastic left heart syndrome is an important sequela. We assessed the risks of the neo-aortic valve deterioration by the difference of initial palliations: Group I underwent primary Norwood (Nw) with systemic-to-pulmonary artery shunt (SPS), Group II underwent bilateral pulmonary artery banding (bPAB) and subsequent Nw with SPS (bPAB-Nw/SPS), Group III underwent bPAB and subsequent Nw with bidirectional Glenn (BDG) procedure (bPAB-Nw/BDG). The neo-aortic valve z score changes over time did not reach statistical significance in all groups (p = 0.43 for Group I, 0.20 for Group II, and 0.30 for Group III). The degree of neo-aortic valve insufficiency did not change significantly over time during this period except for Group III (p = 0.34 for Group I, 0.20 for Group II, and 0.02 for Group III). On the other hand, dimensions of the neo-aortic annulus and degrees of neo-aortic insufficiency did not differ significantly among the 3 groups at any pre-determined time. The presence or absence of incision into the sino-tubular junction at Nw did not affect the late neo-aortic valve z score or insufficiency. These data indicate that the difference of initial palliative procedures does not affect late neo-aortic valve insufficiency in Nw survivors. Because valve failure may develop in longer follow-up, further observation should be conducted.

Long-term results of the Ross procedure in a population-based follow-up

OBJECTIVES

The purpose of this study was to evaluate the long-term outcomes of the Ross procedure in a nationwide follow-up.

METHODS

This retrospective study involved all children treated with the Ross procedure in Finland between 1994 and 2009. The clinical records were reviewed for demographic and anatomical characteristics, Ross operation data, surgical history and status at the latest follow-up. The median follow-up time was 11.5 (range 2.4-19.2) years.

RESULTS

Fifty-one patients underwent either the Ross (n = 37) or the Ross-Konno (n = 14) procedure at a median age of 4.8 (range 0.02-16.3) years, including 13 infants (<1 year of age). The indication for the Ross procedure was aortic valve stenosis, regurgitation or both, which was observed in 29, 24 and 47% of patients, respectively. The early mortality (before hospital discharge) rate was 10% (31% in infants) and the late mortality rate 6% (15% in infants). Higher mortality was discovered in patients treated with the Ross-Konno procedure (P = 0.001). The most common cause for reintervention was pulmonary homograft stenosis. The rate of freedom from right ventricular outflow tract reintervention was 98% at 5 years, 83% at 10 years and 59% at 15 years. The rate of freedom from autograft reintervention was 98% at 5 and 10 years, and 81% at 15 years. At the latest follow-up visit, mild-to-moderate aortic root dilatation was reported in 52% of patients, and 4 patients had undergone autograft-related reinterventions. Trivial autograft valve regurgitation was commonly seen, but only 1 patient developed severe autograft regurgitation requiring mechanical valve replacement 15.9 years after the Ross operation.

CONCLUSIONS

The most common reason for reintervention after the Ross procedure in children is homograft stenosis. Aortic root dilatation and autograft valve regurgitation are relatively common but rarely lead to reinterventions before adulthood. Intraoperative complications and complex cardiac anatomy are associated with high mortality in infants undergoing the Ross-Konno procedure. In our centre, the Ross procedure has provided good long-term results in this challenging group of paediatric patients.

[Role of the Ross-procedure in the management of congenital heart defects]

INTRODUCTION

The surgical strategy to manage multilevel left ventricular outflow tract diseases is changing constantly, however, the Ross-procedure has remained a standard method for 45 years.

AIM

The aim of the study was to analyze early and mid-term results of Ross-procedure in congenital heart defects (single surgeon's results).

METHODS

From 2001 until 2011 a total of 63 patients (age, 28 days-21 years; mean: 10 years, weight 3.4-96 kg; mean, 8.8 kg) underwent Ross (n = 40), Ross-Konno (n = 17) or Ross-Konno-mitral (n = 6) procedures. Indication for Ross procedure was aortic regurgitation in 15 patients (associated with ventricular septum defect in 8 patients) and a predominant aortic stenosis in 25 patients. 17 patients with severe left ventricular outflow tract obstruction underwent Ross-Konno procedure. 6 patients with concomitant mitral valve disease (Shone syndrome, 3 patients; complete atrioventricular septal defect, 3 patients) were reconstructed by Ross-Konno-mitral valve procedure.

RESULTS

Among Ross patients there were one early (cerebral complication) and one late death (homograft endocarditis) with a mean follow-up time of 7.4±1.8 years. Because of an early autograft endocarditis a 3-year-old boy underwent homograft implantation and was treated successfully with Bentall-procedure 9 years later. One patient with autograft regurgitation is waiting for reoperation. Among Ross-Konno patients there was no early or late death, and none of the patients underwent reoperation. In Ross-Konno-mitral patients there was one early death (28-day-old boy) and during a mean follow-up time of 2.5±1 years, and no reintervention or reoperation was needed in 5 patients.

CONCLUSIONS

The results indicate a good outcome of Ross-, Ross-Konno-, Ross-Konno-mitral procedures in patients with congenital heart defects when surgery is performed by a highly experienced heart surgeon. In newborns, infants and small children Ross- and Ross-Konno procedures are the only methods for managing left ventricular outflow tract diseases. Concomitant severe mitral disease adds a high level of technical complexity to the Ross-Konno/mitral procedure, but it should be balanced against alternative strategies (eg. single ventricle palliation or transplantation).

Similarities and differences of the aortic root after arterial switch and ross operation in children

Pulmonary root dilation and valve regurgitation if translocated into the aortic position is frequently seen in children with transposition of the great arteries (TGA) after an arterial switch operation, as well as in patients after the Ross procedure. Many mechanisms are thought to be responsible for the progressive dilation. Despite the differences between the 2 groups, the similarity of having the pulmonary valve and its adjacent tissue working in the systemic circulation might have a comparable effect on the neoaortic root dimensions and elasticity. We prospectively recruited 52 patients with TGA, 23 Ross patients, and 48 healthy subjects for echocardiographic assessment of their aortic valve, root, sinutubular junction, and ascending aortic dimensions and elasticity. The data were compared, stratified by patient age at investigation and the duration of follow-up postoperatively. In relation to the healthy subjects, the neoaortic root dimensions were significantly larger and the tissue stiffer and less distensible in those with TGA and those who had undergone the Ross procedure. Although the pulmonary valve of the Ross patients had been under systemic pressure load for a significantly shorter period (4.4 ± 3.6 vs 10.1 ± 5.5 years), the dimensions and elasticity values had deteriorated more. These differences could neither be clearly attributed to the age differences at surgery or to an auxiliary congenital ventricular septal defect in those with TGA or the aortic valve phenotype before the Ross operation. In conclusion, the worse outcome of the neoaortic root dimensions and elasticity in the Ross patients should at least be partly related to the different predefined pulmonary artery structures and the different development of the normal and transposed pulmonary arteries.

Outcomes of the infant Ross procedure for congenital aortic stenosis followed into adolescence

OBJECTIVES

The Ross procedure is used to treat aortic valve disease in children. The advantages include autograft growth, long-term durability, and avoidance of anticoagulation. Long-term follow-up of the Ross procedure in infancy is limited. We sought to characterize the long-term outcomes of infants undergoing the Ross procedure.

METHODS

We performed a retrospective review of all patients who underwent a Ross operation at 18 months of age or younger at New-York Presbyterian and Cardiothoracic Center of Monaco from 1991 to 2010. The clinical, catheterization, and surgical records were reviewed. The most recent follow-up information, including echocardiogram and electrocardiogram, was obtained and analyzed.

RESULTS

A total of 34 patients underwent a Ross procedure at a median age of 6 months (range, 4 days to 18.4 months). All had congenital aortic stenosis. All but 1 patient had undergone previous surgical or catheter-based interventions. The median follow-up was 10.6 years (range, 1.4-20.4 years). There were 4 early deaths and 1 late transplant. The freedom from right ventricular outflow tract reintervention was 85% at 5 years and 64% at 10 years. The freedom from autograft reintervention was 95.5% at 10 years. In 20 subjects, late follow-up echocardiograms showed a significant difference between the mean early and late Z scores of the autograft annulus (0.8 vs 2.4, P = .03), sinus (0.8 vs 2.8, P = .002), and sinotubular junction (1.2 vs 2.7, P = .04). Mild or less aortic insufficiency occurred in 17 subjects. None had significant aortic stenosis.

CONCLUSIONS

The long-term outcomes of the Ross procedure in infants and toddlers are favorable despite moderate dilatation of the autograft. Reintervention at the right ventricular outflow tract is common.

Aortic valve reconstruction in the young infants and children

Considering the structure and function of the aortic root, changes in the aortic valve leaflets and changes in the geometry of the aortic root are the two primary causes of aortic valve dysfunction. In adults, aortic valve sparing reconstruction has a long history beginning in the 1970s, where tensor fascia was used for leaflet repair in patients with isolated aortic regurgitation and ascending aortic replacement was used in patients with ascending aortic aneurysms or aortic ectasia. Subsequent progress in the 1980s and 1990s led to pericardial leaflet replacement and aortic root re-implantation and remodeling. However, it has not been until the last decade that these concepts and techniques have been applied in younger patients focusing on the conotruncus, valvar apparatus, sino-tubular junction, and ascending aorta.

Aortic valve disease and treatment: the need for naturally engineered solutions

The aortic valve regulates unidirectional flow of oxygenated blood to the myocardium and arterial system. The natural anatomical geometry and microstructural complexity ensures biomechanically and hemodynamically efficient function. The compliant cusps are populated with unique cell phenotypes that continually remodel tissue for long-term durability within an extremely demanding mechanical environment. Alteration from normal valve homeostasis arises from genetic and microenvironmental (mechanical) sources, which lead to congenital and/or premature structural degeneration. Aortic valve stenosis pathobiology shares some features of atherosclerosis, but its final calcification endpoint is distinct. Despite its broad and significant clinical significance, very little is known about the mechanisms of normal valve mechanobiology and mechanisms of disease. This is reflected in the paucity of predictive diagnostic tools, early stage interventional strategies, and stagnation in regenerative medicine innovation. Tissue engineering has unique potential for aortic valve disease therapy, but overcoming current design pitfalls will require even more multidisciplinary effort. This review summarizes the latest advancements in aortic valve research and highlights important future directions.