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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Aortic Valve Repair in Neonates With Aortic Stenosis and Reduced Left Ventricular Function

This study assessed outcomes of neonatal aortic valve (AoV) repair in presumed high-risk patients with depressed left ventricular (LV) function. A retrospective analysis of all neonates who underwent isolated AoV repair for severe aortic stenosis (AS) was performed. Patients with moderate or severe LV dysfunction were compared to those with normal or mild LV dysfunction. From 1980-2021, 43 neonates underwent isolated AoV repair for AS. Of these, 16 patients (37.2%) had ≥moderate LV dysfunction. Mean LV ejection fraction (EF) was 32.8 ± 9.1%. Valve morphology was mostly unicuspid (68.75%, 11/16). Median age at surgery was 6.5 days (IQR 1-17.5). An optimal repair result with ≤mild AS or aortic regurgitation was achieved in 75% (12/16). There was no early death. One patient (6.25%) required postoperative extracorporeal membrane oxygenation (ECMO) support for 3 days. LVEF improved after surgery to 56.4 ± 12.6% before discharge (P < 0.0001) and normalized in 87.5% (14/16) with a median time of 6.4 days (IQR 3.4-39). Freedom from AoV reoperation was 45.1% (95%CI 17.9-69.3%) and 27.1% (95%CI 6.8-53%) at 5 and 10 years, respectively. Freedom from AoV replacement was 59% (95%CI 27-80.8%) and 31.4% (95%CI 6-62.2%) at 5 and 10 years, respectively. While survival was similar, freedom from AoV reoperation and replacement tended to be lower compared to neonates with preserved LVEF. AoV repair was associated with a low incidence of postoperative ECMO and mortality. LV function normalized after relief of obstruction in most patients before discharge. Late reoperation remained common for those with severely dysplastic valves.

Neonatal heart transplant outcomes: A single institutional experience

OBJECTIVE

Neonatal orthotopic heart transplantation was introduced in the 1980s as a treatment for complex congenital heart disease. Progress in single-ventricle palliation and biventricular correction has resulted in a decline in neonatal heart transplant volume. However, limited reports on neonatal heart transplants have demonstrated favorable outcomes. We report the long-term outcomes of patients with neonatal heart transplants at our institution spanning nearly 30 years.

METHODS

A retrospective analysis of neonatal heart transplants and neonates listed for transplant was performed at Children's Hospital Colorado. Primary outcomes were early and late survival. Secondary outcomes were rejection episodes, retransplantation, and development of cardiac allograft vasculopathy or post-transplant lymphoproliferative disease.

RESULTS

A total of 21 neonates underwent orthotopic heart transplantation at our institution. Among these, 10 neonates were transplanted from 1991 to 2000, 8 neonates were transplanted from 2001 to 2010, and 3 neonates were transplanted from 2011 to 2020. The average age of these patients was 17 days, and the average weight was 3.43 kg. Early survival was 95.2%. Survival at 1 and 5 years was 85.7% (confidence interval [CI], 61.9%-95.2%) and 75% (CI, 45.6%-85.5%), respectively. Of eligible patients, the 10-year and 20-year survival was 72.2% (CI, 45.1%-85.3%) and 50% (CI, 25.9%-70.1%), respectively.

CONCLUSIONS

Our institution reports favorable outcomes of neonatal heart transplantation. These results should be considered within the context of outcomes for patients awaiting transplant and the limited donor availability. However, the successful nature of these procedures suggest it may be necessary to reevaluate the indications for neonatal heart transplantation, particularly where risk of mortality and morbidity with palliative or corrective surgery is high.

Ross Operation in Neonates: A Meta-analysis

BACKGROUND

The Ross operation is the preferred treatment for aortic valve replacement in children. However previous studies indicate that outcomes in neonates are poor. This meta-analysis examines the pooled outcomes of the Ross operation in neonates.

METHODS

Four major databases (PubMed/MEDLINE, EMBASE, Scopus, and ScienceDirect) were searched from inception until May 1, 2020 for studies describing outcomes of the Ross operation in neonates. The primary outcome was early mortality, and secondary outcomes were late mortality and mechanical support. Random-effects models were used to account for possible heterogeneity between studies, and continuity corrections were used to include zero total event trials.

RESULTS

Eighteen studies comprising outcomes data on 181 neonates were included in the analysis. Meta-analysis showed a pooled early mortality rate of 24% (95% confidence interval, 12%-38%; I² = 52%, P for heterogeneity = .01). Meta-regression analysis showed that more recently published studies reported significantly worse early mortality (P = .03). The pooled incidence of postoperative mechanical support was 15% (95% confidence interval, 5%-28%; I² = 28%, P for heterogeneity = .22). No evidence of publication bias was found according to Egger's test (bias coefficient = 0.21, P = .57).

CONCLUSIONS

The neonatal Ross operation carries a high early mortality rate. The treatment of unrepairable aortic valves in neonates remains an unsolved problem in congenital cardiac surgery.

Evidence-based surgical hypothesis: Partial heart transplantation can deliver growing valve implants for congenital cardiac surgery

Children undergoing congenital cardiac surgery often outgrow the valve implants. These children are thus committed to morbid reoperations for successive exchanges of the vavular implants that they have outgrown. Therefore the holy grail of congenital cardiac surgery is a valve implant that grows with the recipient child. Preserved homografts routinely are used as valve implants, but they do not grow as the child grows because they lose viability during preservation. In contrast, pulmonary autografts and pediatric heart transplants grow with the recipient children. Similarly, partial heart transplantation can deliver growing valve implants for congenital cardiac surgery. Temporary immune suppression would only be needed until the partial heart transplant can be exchanged for an adult-sized prosthetic valve in the grown child.

A composite semiresorbable armoured scaffold stabilizes pulmonary autograft after the Ross operation: Mr Ross's dream fulfilled

OBJECTIVES

Use of resorbable external reinforcement of the pulmonary autograft during the Ross operation has been suggested, but the differential regional potential for dilation of the aorta, mainly regarding the neo-root and the neo-Valsalva sinuses, represents an unresolved issue. Auxetic materials could be useful in preventing dilation given their favorable mechanical properties. We designed a composite semiresorbable armoured bioprosthesis constituted by polydioxanone and expanded polytetrafluoroethylene and evaluated its effectiveness as a pulmonary autograft reinforcement device in an animal model of the Ross procedure.

METHODS

An experimental model of the Ross procedure was performed in 20 three-month-old growing lambs. The pulmonary autograft was alternatively nonreinforced (control group n = 10) or reinforced with composite bioprosthesis (reinforced group n = 10). Animals were followed up during growth for 6 months by angiography and echocardiography. Specific stainings for extracellular matrix and immunohistochemistry for metalloproteinase-9 were performed.

RESULTS

Reference aortic diameter increased from 14 ± 1 mm to 19 ± 2 mm over 6 months of growth. In the control group, pulmonary autograft distension (28 ± 2 mm) was immediately noted, followed by aneurysm development at 6 months (40 ± 2 mm, P < .001 vs reference). In the reinforced group, an initial dilation to 18 ± 1 mm was detected and the final diameter was 27 ± 2 mm (42% increase). Two deaths due to pulmonary autograft rupture occurred in the control group. On histology, the control group showed medial disruption with connective fibrous replacement, whereas in the reinforced group compensatory intimal hyperplasia was present in the absence of intimal tears. The bioprosthesis promoted a positive matrix rearrangement process favoring neoarterialization and elastic remodeling as demonstrated on specific staining for elastin collagen and metalloproteinase-9.

CONCLUSIONS

The device adapted and functionally compensated for the characteristics of autograft growth, guaranteeing a reasonable size of the autograft at 6 months, but more important, because the device is biocompatible, it did not disrupt the biological process of growth or cause inflammatory damage to the wall.