Geometric mismatch of pulmonary and aortic anuli in children undergoing the Ross procedure: implications for surgical management and autograft valve function

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.

Louis J, Raghuveer G, Kochilas L. Are Mechanical Prostheses Valid Alternatives to the Ross Procedure in Young Children Under 6 Years Old?

BACKGROUND

Aortic valve replacement in young children is associated with technical difficulties and potential morbidity. In contrast to the versatile Ross operation, mechanical prostheses (MP) are uncommonly used.

METHODS

We examined transplant-free survival and cardiac reoperation among 124 young children (aged 1-6 years) who underwent the Ross operation (n = 84) or MP (n = 40) for congenital disease (1982-2003) using the Pediatric Cardiac Care Consortium database. We explored variables influencing outcomes.

RESULTS

Children who received MP were operated in an earlier era and were more likely to have aortic regurgitation, conotruncal abnormalities, prior aortic valve surgery, and to need Konno annular enlargement. Although no significant differences were found in hospital mortality (1.2% vs 5.0%, P = .24) or 15-year transplant-free survival (94.1% vs 87.5%, P = .16) between Ross and MP recipients, survival diverged with later follow-up (91.3% vs 68.9%, respectively, at 25 years; P = .01). On multivariable regression analysis the association of MP use and transplant-free survival changed over time (hazard ratios, 0.8 [95% confidence interval, 0.1-4.4; P = .78] vs 6.0 [95% confidence interval, 0.6-63.1; P = .13], respectively) before and after 17 years. Cumulative incidence of cardiac reoperation at 10 years was 37.7% and 53.6% after the Ross procedure and MP, respectively (P = .05). The most common reoperation after the Ross procedure was conduit replacement and pacemaker ± automated internal cardiac defibrillator and after MP was pacemaker ± automated internal cardiac defibrillator and redo aortic valve replacement.

CONCLUSIONS

Over the study period there was a trend for increased Ross utilization. Interestingly MP use was associated with comparable operative mortality and survival up to 17 years, albeit with higher need for redo aortic valve replacement. On longer follow-up survival diverged with increased attrition in the MP group, likely because of late valve- and reoperation-related complications.

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.

Aortic valve replacement in children: Options and outcomes

Several disease pathologies such as congenital heart disease and rheumatic fever can affect the aortic valve (AV) in children frequently necessitating intervention. While percutaneous or surgical AV repair is recommended as initial management strategy in children with AV disease, AV replacement (AVR) might become necessary in children with significant valve destruction and after repair or intervention failure. AVR in children is associated with distinct clinical and technical problems owing to several anatomic, social and prosthesis-related issues. In the current review, we list different AV substitutes, discuss their advantages and shortcomings, outline AVR results in children, and explore the divergence of outcomes in various age, anatomy and pathology subgroups; all in the aim to identify optimal AVR choice for each patient taking into consideration his unique anatomic and demographic characteristics.

Fate of the remaining neo-aortic root after autograft valve replacement with a stented prosthesis for the failing ross procedure

BACKGROUND

Aortic root replacement (ARR) is advocated for irreparable autograft failure after the Ross procedure to avoid late aneurysm formation. However, redo ARR is complex and associated with bleeding and coronary injury risks. We examine results of autograft valve replacement (AuVR) with stented prostheses (SP) without ARR with special focus on the fate of the remaining root and need for reintervention.

METHODS

Between 1994 and 2011, 50 of 510 Ross patients underwent AuVR with SP. Serial postoperative echocardiograms (n = 342) were analyzed and regression models adjusted for repeated measures were used to model longitudinal change of the remaining root and ascending aorta dimensions after AuVR.

RESULTS

Fifty patients, median age 21 years (range 11 to 50 years) underwent AuVR with SP: mechanical (n = 38) or tissue (n = 12). Thirty patients (60%) had concomitant procedures; most commonly mitral valve surgery (n = 20) or conduit change (n = 12). There were no operative deaths and 10-year survival was 95%. Freedom from prosthesis, root, and all-cause reoperations was 97%, 98%, and 90% at 10 years, respectively. Serial echocardiography data showed that there was little but, nevertheless, progressive increase of the remaining root (EST: +0.0190 [0.0041] cm/year, p < 0.001) and ascending aorta diameters (EST: +0.0191 [0.0037] cm/year, p < 0.001). While there was small steady non-statistically significant increase in mean prosthesis gradient (estimate [EST]: +0.16 [0.09] mm Hg/year, p = 0.08); ejection fraction remained stable with time (EST: -0.12 [0.14] %/year, p = 0.41).

CONCLUSIONS

Our results indicate that AuVR with SP without ARR for failing autografts is justified as it is associated with low mortality and reoperation risk. Preemptive complex ARR should be reserved for those with significant root dilatation at time of AuVR. Although root reinterventions are rare, patients should be followed for progressive root dilatation. Faster growth is seen in those who fail with regurgitation and dilated annulus.

The fate of the neoaortic valve and root after the modified Ross-Konno procedure

OBJECTIVES

In children with aortic valve disease associated with annular hypoplasia or complex multilevel left ventricular outflow tract obstruction, the Ross procedure, combined with a modified Konno-type aortoventriculoplasty, is advocated. We aim to examine the fate of the neoaortic apparatus and assess neoaortic valve function after the modified Ross-Konno procedure.

METHODS

Forty-three patients, with a median age of 6 years, underwent the modified Ross-Konno procedure with a myectomy but without the use of a ventricular septal patch. Serial postoperative echocardiograms (n = 187) were analyzed, and regression models adjusted for repeated measures were used to model the longitudinal growth of the neoaortic annulus and root.

RESULTS

There were 2 operative deaths (5%) and 1 late mortality. At 8 years, survival was 93% and freedom from autograft, homograft, and all-cause reoperation was 100%, 81%, and 72%, respectively. The median postprocedure diameter and z score were 14 mm (7-21 mm) and +1.3 (-3.0 to +6.1) for the neoaortic annulus and 21 mm (9-30 mm) and +1.6 (-1.3 to +4.1) for the neoaortic root, respectively. Serial echocardiograms showed a progressive increase in annular (+0.56 mm/year, P < .001) and root (+0.89 mm/year, P < .001) diameters but little change in annular (-0.07/year, P = .08) and root (-0.002/year, P = .96) z scores. Autograft regurgitation developed in 9 patients; however, the degree and progression of regurgitation over time were not significant (P = .22).

CONCLUSIONS

After the modified Ross-Konno procedure, the neoaortic annulus and root increased in size proportionately to somatic growth. Autograft regurgitation, usually mild and stable, developed in few patients, and none required autograft reoperation. Our findings support the use of the modified Ross-Konno as the procedure of choice in children with aortic valve disease and complex left ventricular outflow tract obstruction.

Accuracy of intraoperative transesophageal echocardiography in the prediction of future neo-aortic valve function after the Ross procedure in children and young adults

OBJECTIVE

Neo-aortic insufficiency (neo-AI) has been noted following the Ross procedure. The purpose of this study was to evaluate the ability of intraoperative transesophageal echocardiography (TEE) to predict future neo-AI in pediatric patients undergoing the Ross from January 1995 to December 2003, who had an intraoperative TEE, and discharge and follow-up transthoracic (TTE) echocardiograms.

DESIGN

Retrospective case series.

PATIENTS

All patients who underwent the Ross procedure at Children's Hospital of Philadephia between January 1995 and December 2003, and had an intraoperative TEE, discharge, and follow-up (>6 months) transthoracic echocardiogram (TTE) (by July 1, 2004) were included.

OUTCOME MEASURES

Grade of neo-AI was assessed on intraoperative TEE, discharge, and follow-up TTE echocardiogram reports.

RESULTS

Follow-up was available in 99/115 (86%) survivors. Median age at Ross was 9.3 years (4 days-34 years). No patient had more than mild neo-AI on intraoperative TEE. At discharge, 2 patients (2%) had moderate neo-AI. At most recent follow-up (median 4.2 years, 8 months-9.3 years), 21 patients (21%) had moderate or greater neo-AI; 9 underwent neo-aortic reintervention. The presence of any neo-AI on intraoperative TEE had 100% sensitivity and negative predictive value for diagnosing moderate or greater neo-AI at discharge. Patients who had mild neo-AI on TEE were more likely to have moderate or greater neo-AI at most recent follow-up than those patients with no neo-AI on TEE (9% vs. 30%, P = 0.01).

CONCLUSION

Intraoperative TEE is an excellent screening tool for the presence of significant neo-AI at the time of hospital discharge. Neo-AI progresses over time after Ross procedure and is more likely to progress in those patients with neo-AI on intraoperative TEE. However, predictive validity decreases over time as neo-AI progresses.

The Relationship Between Neo-Aortic Root Dilation, Insufficiency, and Reintervention Following the Ross Procedure in Infants, Children, and Young Adults

OBJECTIVES

The purpose of this study was to describe the relationship between neo-aortic root size, neo-aortic insufficiency (AI), and reintervention at mid-term follow-up.

BACKGROUND

Data on neo-aortic valve function and growth after the Ross procedure in children are limited.

METHODS

A total of 74 of 119 Ross patients from January 1995 to December 2003 had > or =2 follow-up echocardiograms at our institution and were included. Neo-aortic dimensions were converted to z-scores and modeled over time. Kaplan-Meier analysis was used to assess freedom from neo-aortic outcomes, and predictors were identified through multivariate analysis.

RESULTS

Median age at Ross was 9 years (range 3 days to 34 years). Over 4.7 years (range 3 months to 9.3 years) follow-up, there was disproportionate enlargement of the neo-aortic root (z-score increase of 0.75/year [p < 0.0001]). Neo-AI progressed > or =1 grade in 36% of patients and > or =2 grades in 15%. Nine patients (12%) had neo-aortic reintervention at 2.0 years (range 1.1 to 9.5 years) after the Ross procedure owing to severe neo-AI (n = 7), neo-aortic root dilation (n = 1), and neo-aortic pseudoaneurysm (n = 1). At 6 years after the Ross procedure, freedom from neo-aortic reintervention was 88%. Freedom from neo-aortic root z-score >4 was only 3% and from moderate or greater neo-AI was 60%. Longer follow-up time was associated with neo-aortic root dilation (p < 0.0001). Prior ventricular septal defect (VSD) repair predicted neo-AI (p = 0.02) and reintervention (p = 0.03). Prior aortic valve replacement (p = 0.002) also predicted neo-AI. Neo-aortic root dilation was not associated with neo-AI or reintervention.

CONCLUSIONS

At mid-term follow-up after the Ross procedure, neo-aortic root size increases significantly out of proportion to somatic growth, and neo-AI is progressive. Prior VSD repair and aortic valve replacement were associated with neo-AI and reintervention.

Midterm outcomes and predictors of reintervention after the Ross procedure in infants, children, and young adults

OBJECTIVES

This study assessed the type, time course, and risk factors for right and left ventricular outflow tract reinterventions after the Ross procedure in a population of infants, children, and young adults.

METHODS

Patients who underwent the Ross procedure between January 1995 and June 2004 were included (n = 121 consecutive patients). Kaplan-Meier and hazard analyses of right and left ventricular outflow tract reinterventions were performed, and predictors of reintervention were identified through multivariate analysis.

RESULTS

The median age at the Ross procedure was 8.2 years (4 days to 34 years); 20% were aged less than 1 year. Half of the patients had isolated aortic valve disease; the other half had complex left-sided heart disease. Early mortality (<30 days) was 2.5% (n = 3). There were 2 late deaths (1.7%). Follow-up (median 6.5 years [2.5 months to 10.4 years]) was available for 96% of survivors (n = 111). Right ventricular outflow tract reintervention (n = 22 in 15 patients) was performed 2.0 years (2.0 weeks to 9.8 years) after the Ross procedure because of stenosis in 19 of 22 cases. Freedom from right ventricular outflow tract reintervention at 8 years was 81%. Smaller homograft size was the strongest predictor (P < .001) of right ventricular outflow tract reintervention. Left ventricular outflow tract reintervention (n = 15 in 15 patients) was performed 2.8 years (1.0 months to 11.6 years) after the Ross procedure because of severe neoaortic insufficiency in 10 of 15 patients. Freedom from left ventricular outflow tract reintervention at 8 years was 83%. Native pulmonary valve abnormalities (P < .01), original diagnosis of aortic insufficiency (P < .01), prior aortic valve replacement (P = .01), and prior ventricular septal defect repair (P = .04) predicted left ventricular outflow tract reintervention.

CONCLUSIONS

At midterm follow-up after the Ross procedure, interim mortality is rare. Neoaortic insufficiency and right ventricle to pulmonary artery conduit obstruction are common postoperative sequelae, requiring reintervention in one quarter of patients.

What is the proper place of the ross procedure in our modern armamentarium?

Despite nearly four decades of experience, the role of pulmonary valve autotransplantation (Ross procedure) in the treatment of aortic valve disease in adults and children continues to evolve and remains controversial. As the picture of late results has unfolded, alternating waves of enthusiasm and caution have characterized its use and have led to ongoing refinements in indications and operative technique. At present, it is seen as indispensable in the treatment of aortic valve disease in infants and small children (for whom no satisfactory replacement alternative exists and for whom growth is essential), attractive for adolescents and young adults who wish to avoid anticoagulants because of childbirth and lifestyle considerations, a reasonable option for selected adults who desire biologic solutions with potentially better durability than conventional bioprostheses, and contraindicated for the elderly and those with connective tissue disorders. Young patients with bicuspid aortic valve are the most common potential recipients, but also the most controversial, because of the risk of autograft dilatation. Optimal matching of prosthesis to patient is a clinical challenge for all caretakers involved in the treatment of valvular heart disease; this review provides guidelines to identify those patients who will benefit most from the Ross procedure, and those for whom it is inadvisable.

The Ross Procedure

BACKGROUND

The search for the ideal substitute for the aortic valve led Donald Ross to develop the pulmonary autograft concept in 1967. A historical, technical, and scientific review of this surgical option is presented together with our clinical experience.

MATERIALS AND METHODS

The literature is reviewed to identify the advantages and pitfalls of the Ross procedure over the last decades. We also present our clinical experience with 92 patients operated between 1997 and May 2003.

RESULTS

Of the total, 70.65% (n = 65) were males, mean age was 29.32 +/- 11.9 years, with 20 patients under 16 and 6 patients under 10 years. Twenty-five patients (27.17%) had 31 previous interventions. There were 41 associated procedures in 34 patients. Perioperative mortality was 2.17% (two patients). Eight patients required reexploration for bleeding, one required an aortocoronary bypass, and one a permanent pacemaker. Follow-up was 97% with 2.71 patients/year (average 32.55 +/- 19.01 months). Two patients required autograft replacement, one suffered a 44-mm dilatation of the autograft, and one 13-year-old girl developed autograft endocarditis. Six patients suffered severe homograft stenosis (>50 mmHg), two were treated percutaneously, and one required replacement. Combined freedom from reintervention is 93.56 +/- 2.81% at 5 years.

CONCLUSIONS

The Ross procedure is a mature concept with thousands of patients operated worldwide and a cumulative experience of over 30 years. Although we believe that it is the procedure of choice in the pediatric population, women in child-bearing age, and substantial subgroups of adult patients, efforts must continue to minimize the incidence of auto- and homograft failure in the long term.

Aortopulmonary size discrepancy is not a contraindication to the pediatric Ross operation

BACKGROUND

Modification of the aortic annulus or the ascending aorta, or both, may be required in pediatric patients undergoing the Ross operation. The fate of these autografts remains uncertain.

METHODS

Retrospective review of 15 patients undergoing Ross operation without aortic annular modification (group 1), 11 patients requiring annular reduction (group 2, n = 11), and 8 patients requiring annular enlargement (group 3, n = 8). Autograft function and dimensions were evaluated by echocardiography.

RESULTS

Autograft insufficiency was less than or equal to mild in 33 patients and moderate in 1 patient. The annulus body surface area ratio increased in group 1 from 19.7 +/- 5 to 20.3 +/- 5 mm/M2 (p = 0.8). The average annular reduction in group 2 was 5 +/- 1.5 mm, and 10 of 11 patients required reduction of the ascending aorta (mean 11 +/- 5 mm). The annulus body surface area ratio increased from 18.6 +/- 7 to 20.5 +/- 9 mm/M2 (p = 0.2). The mean augmentation in annulus diameter in group 3 was 6 +/- 4 mm; the annulus body surface area ratio decreased from 23.7 +/- 14 to 20.3 +/- 8 mm/M2 (p = 0.5).

CONCLUSIONS

We continue to offer the Ross operation to pediatric patients even when aortic annular or ascending aortic size discrepancies mandate surgical modifications.

Valves in development for autogenous tissue valve replacement

Currently available valve and conduit artery substitutes have one or more significant disadvantages including limited durability, thrombogenicity, susceptibility to infection, and a lack of growth potential. Prior attempts to use autologous tissues in the construction of valve or arterial substitutes to overcome some of these limitations have not been successful. The use of tissue engineering techniques to construct valve and arterial substitutes from individual autologous cell lines and biodegradable polymer scaffolds are now under investigation in the laboratory, and the initial short term results in animals have been encouraging. These tissue engineering techniques offer the possibility of creating structures for replacement of valves and conduit arteries which are viable and have the capacity for self-repair and therefore greater durability. In addition, these structures should be non-thrombogenic and less susceptible to infection, and will have growth potential. Copyright 1999 by W.B. Saunders Company

The Ross procedure in children and young adults: a word of caution

BACKGROUND

Disease of the aortic valve in children and young adults is a complex entity whose management is the subject of controversy. The Ross and the Ross-Konno procedures have become the primary choices for aortic valve replacement in children because of growth potential, optimal hemodynamic performance, and lack of the need for anticoagulation. However, concern persists regarding the longevity of the pulmonary autograft, especially in patients with aortic insufficiency.

METHODS

Between June 1993 and February 2000, 72 Ross and Ross-Konno procedures were performed at our institution: 81% of the patients were less than 15 years old. Preoperative, postoperative, and follow-up clinical, echocardiographic, and hemodynamic data were reviewed. Statistical analysis was performed to identify the risk factors for deteriorating autograft function.

RESULTS

Aortic insufficiency was an indication for the Ross procedure in 17 patients and mixed lesions with predominant aortic insufficiency in 10. Of the 45 other patients, 32 had aortic stenosis and 13 had mixed lesions with predominant aortic stenosis. There were no deaths during a follow-up of 5 to 80 months. Autograft reoperation was necessary in the follow-up period in 7 patients for severe aortic insufficiency. Moderate insufficiency was identified in 5 additional patients. Aortic insufficiency or predominant aortic insufficiency, as a preoperative hemodynamic indication for the Ross procedure, reached statistical significance (P =.031) as a risk factor for autograft failure.

CONCLUSION

The Ross and the Ross-Konno procedures have changed the prognosis of children and young adults with complex aortic valve disease. However, the Ross procedure should be performed with caution in older children in whom aortic insufficiency is a preoperative hemodynamic indication. Further follow-up to delineate the risk factors for autograft dysfunction in children and young adults is necessary to better define the indications for the Ross procedure.

Midterm results of the Ross procedure

BACKGROUND

The optimal hemodynamic performance and potential growth of the pulmonary autograft has led to expanded indications for the Ross procedure. We reviewed our institutional experience to assess midterm results with the Ross operation.

METHODS

In a 7-year period (1992 to 1999), 111 patients with a median age of 15.7 years (range 2 days to 67 years), underwent the Ross procedure. Ninety-five patients had isolated aortic valve disease and 16 pediatric patients had a more complex left ventricular outflow tract obstruction.

RESULTS

There were 3 early (2.7%) and 3 late deaths over a median follow-up of 3.6 years (range 6 months to 7.6 years). Actuarial survival at 5 years was 94%+/-2%. In pediatric patients, the pulmonary autograft annulus enlarged from 14.7+/-6.2 mm to 22+/-6.3 mm. This growth followed the expected increase in pulmonary valve diameter based on body surface area. Eight reoperations were necessary for autograft insufficiency at a median interval of 14 months (range 2 days to 31 months). Freedom from replacement of the pulmonary autograft was 91%+/-3% at 5 years. Three patients developed important obstruction of the pulmonary homograft requiring reoperation at a median of 29 months (range 9 to 31 months).

CONCLUSIONS

The Ross procedure can be performed with good midterm results. In pediatric patients, autograft growth has been appropriate. The potential for development of important autograft insufficiency suggests close follow-up through the intermediate and late term.

Issues and outcomes in the management of supravalvar aortic stenosis

BACKGROUND

Supravalvar stenosis of the aorta is an uncommon congenital cardiac anomaly that involves not only the supravalvar aorta but the entire aortic root. Despite considerable attention to the importance of maintaining the integrity of the aortic root during supravalvar reconstruction, there has been little focus on the management of other components of the aortic root and left ventricular outflow tract, including the aortic valve, subvalvar region, and coronary arteries.

METHODS

We reviewed the records of 36 consecutive patients with supravalvar aortic stenosis who underwent repair from 1992-1998 (median age, 4 years). Discrete stenosis was present in 29 patients, whereas the remaining 7 had the diffuse form of the disease. Associated anomalies of the aortic root and adjacent structures were present in 23 patients. The median pressure gradient across the left ventricular outflow tract was 70 mm Hg. Supravalvar stenosis was relieved by extended aortoplasty with a Y-shaped patch in 18 patients, resection of the stenotic segment of ascending aorta at the sinotubular junction with end-to-end anastomosis of the ascending aorta in 7, the Ross procedure in 4, and other techniques in 7. Additional procedures included aortic valvuloplasty in 10 patients, resection of subvalvar stenosis in 11, and procedures on the coronary arteries in 2.

RESULTS

There was 1 perioperative death, and no reoperations or other significant complications. During follow-up (median 33 months), there were no deaths and 3 reoperations for replacement of the aortic valve with a pulmonary autograft (n = 1) or mechanical prosthesis (n = 2). The median pressure gradient across the left ventricular outflow tract was 10 mm Hg.

CONCLUSIONS

In patients with supravalvar aortic stenosis, abnormalities of the aortic valve, subaortic region, and coronary arteries are frequently present as well. Management of these issues is as critical to the long-term outcome of these patients as reconstruction of the supravalvar aorta. Aggressive valvuloplasty may help decrease the incidence of late aortic valve replacement, whereas the Ross procedure may be a preferable approach in some patients with complex outflow tract obstruction.

Intermediate-term results in pediatric aortic valve replacement

BACKGROUND

Aortic valve replacement (AVR) in children is now more commonly performed with human tissue valves.

METHODS

The results of 100 consecutive pediatric AVRs (50 mechanical, 50 human) were reviewed.

RESULTS

There were five perioperative deaths in the mechanical group and one in the human group (p = 0.2). Late complications in the mechanical group included 4 late deaths, 2 cases of endocarditis, 3 thromboembolic complications, and 10 reoperations on the aortic valve. In the human group, there were no late deaths, 2 reoperations for allograft aortic valve deterioration (both in Marfan's patients), and 1 reoperation for allograft pulmonary valve stenosis. Four-year actuarial survival was 83% in the mechanical group and 98% in the human group (p = 0.02). Four-year actuarial survival free of all valve-related complications was 61% in the mechanical group and 88% in the human group (p = 0.008).

CONCLUSIONS

Human valves in children requiring AVR provide superior intermediate-term survival and freedom from valve-related complications compared to mechanical valves. Marfan's syndrome may represent a rare remaining contraindication for human AVR in children.

Acceptance and versatility of the Ross procedure

During the 31 years since the initial Ross procedure, data have been collected that have been helpful in assessing long-term performance of the autograft. The ongoing study of the pulmonary autograft supports the use of the Ross procedure in young patients, in females of childbearing age, and in patients with congenital aortic stenosis and complex left ventricular outflow tract obstruction. We continue to see little or no thromboembolism despite no anticoagulation therapy. The remarkable ability of the autograft to grow in children is extremely beneficial. Additionally, excellent results have been obtained in some series for the treatment of endocarditis. Recently, the autograft has performed similarly to a normal aortic valve under high stress. Changes in implantation techniques transitioning from subcoronary to root replacement and performing annular narrowing has decreased the incidence of early regurgitation. A potential for an immune response with resulting pulmonary stenosis and possible early explanation of the pulmonary homograft exists; however, overall, results of the Ross procedure are excellent and highly reproducible.