Systemic obstruction in univentricular hearts: surgical options for neonates

Pulmonary Artery Banding and Arch Repair vs Norwood for Unbalanced Atrioventricular Canal Defect

BACKGROUND

The outcomes of single-ventricle palliation in unbalanced atrioventricular canal defect with coarctation of aorta (uAVC+CoA) have not been well studied. Systemic ventricle outflow tract obstruction has a propensity to develop in these patients after aortic arch repair with pulmonary artery banding (arch-PAB), which may adversely affect survival and Fontan candidacy.

METHODS

A retrospective review was performed of patients who underwent single-ventricle palliation for uAVC+CoA from 2000 to 2022. Patients were divided into 2 groups based on initial palliation: (1) arch-PAB and (2) Norwood procedure. Demographic and clinical characteristics were analyzed and compared along with survival data.

RESULTS

Stage 1 palliation for uAVC+CoA was performed in 41 patients. Arch-PAB was performed in 14 infants and Norwood in 27 infants. Arch-PAB patients had more chromosomal abnormalities (28.6 vs 7.4%, P < .009) and less severe systemic ventricle outflow tract obstruction on baseline echocardiogram (0.0 vs 70.4%, P < .001). Survival to stage 3 palliation was lower for the arch-PAB group (28.6% vs 66.6%, P = .02). Arch-PAB remained a significant risk factor for mortality (hazard ratio, 2.93; 95% CI, 1.05-8.53; P = .04) after adjusting for chromosomal abnormalities and atrioventricular valve regurgitation. After arch-PAB, systemic ventricle outflow tract obstruction was diagnosed in 13 of 14 patients. Echocardiography underestimated the degree of outflow tract obstruction in 10 of 13 arch-PAB patients.

CONCLUSIONS

Arch-PAB has worse outcomes than Norwood for uAVC+CoA. Systemic ventricle outflow tract obstruction develops in almost all patients after arch-PAB. Outflow tract obstruction is underestimated by the echocardiogram and requires a high index of suspicion, along with advanced imaging, to ensure timely diagnosis and management.

Comparing palliation strategies for single-ventricle anatomy with transposed great arteries and systemic outflow obstruction

Objective

Patients with complex single-ventricle anatomy with transposed great arteries and systemic outflow obstruction (SV-TGA-SOO) undergo varied initial palliation with ultimate goal of Fontan circulation. We examine a longitudinal experience with multiple techniques, including the largest published cohort following palliative arterial switch operation (pASO), to describe outcomes and decision-making factors.

Methods

Neonates with SV-TGA-SOO who underwent initial surgical palliation from 1995 to 2022 at a single institution were retrospectively reviewed.

Results

In total, 71 neonates with SV-TGA-SOO underwent index surgical palliation at a median age of 7 days (interquartile range, 6-10) by pASO (n = 23), pulmonary artery band (PAB) with or without arch repair (n = 25), or modified Norwood with Damus-Kaye-Stansel aortopulmonary amalgamation (n = 23). Single-ventricle pathology included double-inlet left ventricle (n = 37, 52%), tricuspid atresia (n = 27, 38%), and others (n = 7, 10%). All mortalities (n = 5, 7%) occurred in the first interstage period after PAB (n = 3) and Norwood (n = 2). Subaortic obstruction in the PAB group was addressed by operative resection (n = 10 total, 7 at index operation) and/or delayed aortopulmonary amalgamation (n = 13, 52%). Two patients with pASO (9%) had early postoperative coronary complications, 1 requiring operative revision. Median follow-up for survivors was 10.4 years (interquartile range, 4.5-16.6 years). Comparing patients by their initial palliation type, notable significant differences included size of bulboventricular foramen, weight at initial operation, operation duration, postoperative length of stay, time to second-stage palliation, multiple pulmonary artery reinterventions, and left pulmonary artery interventions. There were no significant differences in overall survival, Fontan completion, reintervention-free survival in the first interstage period, pulmonary artery reintervention-free survival, long-term systemic valve competency, or ventricular dysfunction.

Conclusions

Excellent mid- to long-term outcomes are achievable following neonatal palliation for SV-TGA-SOO via pASO, PAB, and modified Norwood, with comparable survival and Fontan completion. Initial palliation strategy should be individualized to optimize anatomy and physiology for successful Fontan by ensuring an unobstructed subaortic pathway and accessible pulmonary arteries. pASO is a reasonable strategy to consider for these heterogeneous lesions.

The choice of palliative arterial switch operation as an alternative for selected cases in a single center: Experience and mid term results

INTRODUCTION AND OBJECTIVE

There are various management options for newborns with single ventricle physiology, ventriculoarterial discordance and subaortic stenosis, classically involving the early pulmonary banding and aortic arch repair, the restricted bulboventriculer foramen enlargement or the Norwood and the Damus-Kaye-Stansel procedures. The aim of this study is to evaluate our preferred technique and comment on the midterm results of our clinical experience with palliative arterial switch operation (pASO) for a certain subset of patients.

METHOD

We hereby retrospectively evaluate the charts of patients who went through pASO, as initial palliation through Fontan pathway, starting from 2014 till today.

RESULTS

Ten patients underwent an initial palliative arterial switch procedure. Eight of 10 patients survived the operation and discharged. Seven of 10 patients completed Stage II and 1 patient reached the Fontan completion stage and the other six of ten (6/10) patients are doing well and waiting for the next stage of palliation. There are two mortalities in the series (2/10) and one patient lost to follow-up (1/10).

CONCLUSION

In our opinion, the pASO can be considered as an alternative palliation option for patients with single ventricle physiology, transposition of the great arteries and systemic outflow tract obstruction despite longer cross clamp times compared to other methods, but It not only preserves systolic and diastolic ventricular function, but also provides a superior anatomic arrangement for following stages.

Long-Term Outcome of Direct Relief of Subaortic Stenosis in Single Ventricle Patients

Background:

Single ventricle patients with unrestrictive pulmonary blood flow and (potential) subaortic stenosis are challenging to manage and optimal surgical strategy is unknown. Direct relief of subaortic stenosis by enlargement of the ventricular septal defect and/or subaortic chamber has generally been replaced by a Damus-Kaye-Stansel or Norwood procedure due to concerns of iatrogenic heart block, reobstruction, or ventricular dysfunction. Studies reporting long-term outcome after the direct approach are limited. The aim of our study was to describe and analyze our experience with direct relief of subaortic stenosis in single ventricle patients.

Methods:

Demographic data, characteristics, and pre-operative, operative and outcome details were collected for children undergoing direct relief of subaortic stenosis between 1989 and 2016.

Results:

Twenty-three patients (median age: 7.4 months, range: 10 days to 5.5 years) underwent direct relief of subaortic stenosis. Complete follow-up was available for all patients (median: 15.6 years, range: 34 days to 26.3 years). Seven (30%) patients had recurrence of subaortic stenosis. One (4%) patient developed complete heart block and one patient developed moderate ventricular dysfunction. Five (50%) patients developed a (pseudo)aneurysm at site of the patch and ventriculotomy. There were two perioperative deaths. Eighty-six percent of patients underwent a successful Fontan procedure.

Conclusions:

Direct relief of subaortic stenosis is associated with a substantial risk of reobstruction and patch (pseudo)aneurysm formation. However, risk of heart block is low and long-term outcome is good with the majority of patients reaching Fontan completion. In our opinion, the direct approach appears to be a good and relatively simple procedure in selected cases for the treatment of subaortic stenosis.

Palliation Outcomes of Neonates Born With Single-Ventricle Anomalies Associated With Aortic Arch Obstruction

BACKGROUND

The two most common surgical strategies for the treatment of neonates born with single-ventricle anomalies associated with aortic arch obstruction are the Norwood operation and pulmonary artery banding plus coarctation repair (PAB+COA). We reviewed characteristics and outcomes of neonates who underwent those two surgical strategies at our institution.

METHODS

Between 2002 and 2012, 94 neonates with a single ventricle and aortic arch obstruction (excluding hypoplastic left heart syndrome) underwent Norwood (n = 65) or PAB+COA (n = 29). Outcomes were parametrically modeled, and risk factors associated with early and late death were analyzed.

RESULTS

Competing-risks analysis showed that, at 2 years after the operation, 24% of patients had died or received transplantation and 75% had undergone a Glenn shunt. At 5 years after the Glenn shunt, 10% of patients had died or received transplantation, 62% had undergone Fontan, and 28% were alive awaiting Fontan. Overall 8-year survival was 70%. Outcomes after Norwood included extracorporeal membrane oxygenation use in 9 (14%), unplanned reoperation in 13 (20%), hospital death in 10 (15%), and interstage death in 8 (12%), with 8-year survival of 66%. Outcomes after PAB+COA included extracorporeal membrane oxygenation use in 1 (3%), unplanned reoperation in 9 (30%), hospital death in 1 (3%), and interstage death in 3 (10%), with 8-year survival of 76%. There was an association trend between underlying anatomy and survival (hazard ratio [HR], 2.1; 95% confidence interval [CI], 0.9 to 4.7; p = 0.087). On multivariable analysis, factors associated with death were extracorporeal membrane oxygenation use (HR, 5.5; 95% CI, 1.9 to 15.9; p = 0.002), genetic syndromes/extracardiac anomalies (HR, 3.5; 95% CI, 1.5 to 8.2; p = 0.003), and weight of 2.5 kg or less (HR, 3.0; 95% CI, 1.3 to 7.2; p = 0.012).

CONCLUSIONS

Anatomic and patient characteristics influence palliation outcomes in neonates born with single-ventricle anomalies associated with aortic arch obstruction. Although the Norwood operation is applicable in most of these patients, the PAB+COA strategy is a valid alternative in well-selected patients.

Influence of Morphology and Initial Surgical Strategy on Survival of Infants With Tricuspid Atresia

BACKGROUND

Tricuspid atresia (TA) is a heterogeneous single-ventricle anomaly in which initial presentation and, consequently, timing and mode of palliation vary based on morphology and degree of pulmonary or systemic outflow obstruction. We report current era palliation outcomes and examine whether morphologic and, subsequently, surgical factors influence survival.

METHODS

From 2002 to 2012, 105 infants with TA underwent surgical palliation. Competing risks analyses modeled events after first-stage surgery (Glenn versus death) and after Glenn (Fontan versus death) and examined risk factors affecting outcomes.

RESULTS

Seventy-eight patients (74%) required neonatal first-stage palliation, including modified Blalock-Taussig shunt (n = 46, 44%), Norwood (n = 18, 17%), and pulmonary artery band (n = 14, 13%), whereas 27 (26%) received primary Glenn as their initial surgery. Hospital mortality was 5 patients (4.8%). Competing risks models showed that by 1 year after first-stage surgery, 15% of patients had died and 83% had undergone Glenn. By 5 years after Glenn, 2% of patients had died and 80% had undergone Fontan. Overall 8-year survival was 84%. On multivariable analysis, risk factors for mortality were genetic/extracardiac anomalies (hazard ratio 7.0, 95% confidence interval: 2.4 to 20.6, p < 0.001) and pulmonary atresia (hazard ratio 4.4, 95% confidence interval: 1.6 to 12.2, p = 0.004). Survival was not affected by initial palliation type (p = 0.36), ventriculoarterial discordance (p = 0.25), systemic outflow obstruction (p = 0.84), or arch obstruction (p = 0.62).

CONCLUSIONS

Despite morphologic and physiologic variations necessitating different palliative sequences, multistage palliation outcomes of various TA subtypes are comparable and generally good, with the exception of patients with associated genetic/extracardiac anomalies. The bulk of mortality is interstage, indicating continued opportunity for improvement in monitoring and managing patients during this critical period.

Current Outcomes of the Norwood Operation in Patients With Single-Ventricle Malformations Other Than Hypoplastic Left Heart Syndrome

Background:

Subsequent to increased experience with the Norwood operation in children with hypoplastic left heart syndrome (HLHS), its application has expanded to allow palliation of single-ventricle (SV) malformations other than HLHS. We describe current palliation outcomes in this group of SV patients.

Methods:

Between 2002 and 2012, 65 of the 303 Norwood operations were performed in non-HLHS SV patients. Competing risk analysis modeled events after Norwood and after subsequent Glenn and examined risk factors affecting outcomes.

Results:

Competing risk analysis showed that one year following Norwood, 24% of patients had died or received transplantation, 72% had undergone Glenn, and 4% were alive awaiting Glenn/Kawashima. Five years following Glenn, 9% of patients had died, 68% had undergone Fontan, and 23% were alive awaiting Fontan. Overall seven-year survival following Norwood was 68%. On multivariable analysis, mortality risk factors were unplanned cardiac reoperation (hazard ratio [HR]: 4.0 [1.5-10.6], P = .006), right dominant ventricle morphology (HR: 3.3 [1.3-8.3], P = .012), and postoperative extracorporeal membrane oxygenation (HR: 3.1 [1.1-9.0], P = .035).

Conclusions:

Operative death and interstage mortality continue to be problematic following Norwood palliation for non-HLHS SV variants. Outcomes seem comparable to those reported for HLHS, however they are influenced by underlying pathology; children with dominant left ventricle morphology (tricuspid atresia and double inlet left ventricle) have superior survival compared to those with dominant right ventricle morphology (mitral atresia, unbalanced atrioventricular septal defect, and most patients with atrial isomerism). Unplanned reoperations for technical imperfections diminish survival. Large multicenter studies might be warranted to better identify high-risk patients and provide guidance toward improving their survival.

Outcomes of patients born with single-ventricle physiology and aortic arch obstruction: the 26-year Melbourne experience

BACKGROUND

To review the long-term outcomes of patients born with single-ventricle physiology and aortic arch obstruction.

METHODS

Follow-up of 70 consecutive neonates undergoing single-ventricle palliation and arch repair, excluding hypoplastic left heart syndrome, between 1983 and 2008, was reviewed. Dominant arch anomalies were coarctation (n = 48), interrupted arch (n = 10), and hypoplastic arch alone (n = 12). Neonatal Damus procedure with arch repair and shunt became the dominant approach, being performed in 1 (10%) of 10 in 1983 to 1989, 9 (32%) of 28 in 1990 to 1999, and 23 (72%) of 32 in 2000 to 2008.

RESULTS

All patients underwent an initial procedure at a median of 6 days (range, 4-12 days): pulmonary artery banding and arch repair (n = 35); Damus, arch repair, and shunt (n = 33); and other (n = 2). Twenty-six patients died before Fontan completion. Of the 34 survivors of initial banding, 17 (50%) later required a Damus and 4 (12%) required subaortic stenosis relief. Forty patients underwent Fontan completion at a median age of 5 years (range, 4-7 years). After a mean of 5 ± 6 years after Fontan, there was 1 hospital death and 1 Fontan takedown. Overall survival was similar if patients initially underwent a Damus or pulmonary artery banding (P = .3). Overall survival at 10 years was 53% (95% confidence interval, 42%-67%).

CONCLUSIONS

Patients born with single-ventricle physiology and arch obstruction have a high risk of mortality in the first years of life. Their outcomes seem excellent once they reach Fontan status. It is likely that, in patients with single-ventricle and arch obstruction, strategies to avoid systemic outflow tract obstruction should be implemented in early life, and regular monitoring of blood pressure is warranted.

Management of the single ventricle and potentially obstructive systemic ventricular outflow tract

Multi-stage palliation is the current management strategy for the treatment of children with various single ventricle (SV) cardiac malformations. The success of this strategy depends on the presence of favorable anatomic and hemodynamic criteria. Several SV anomalies have the potential of developing systemic ventricular outflow tract obstruction (SVOTO) that might be evident early on or progress later after palliative surgeries. SVOTO could result in ventricular hypertrophy, impaired diastolic function and subendocardial ischemia with subsequent deleterious effects on the SV and disturbance of some of those criteria for a successful multi-stage palliation strategy. Careful identification of SV patients at risk of developing SVOTO and proper planning of the optimal palliation sequence beginning at the 1st stage procedure are vital factors that would affect long-term outcomes in those patients. In the current review, we describe the morphology of SV patients with potential SVOTO risk, surgical procedures that address potential or present SVOTO, and optimal timing of those procedures within the multi-stage palliation chain. We attempt to provide a treatment algorithm for various patients taking into consideration their unique anatomic and physiologic characteristics.

Fifteen-year single-center experience with the Norwood operation for complex lesions with single-ventricle physiology compared with hypoplastic left heart syndrome

OBJECTIVE

The Norwood procedure, the first surgical step of staged palliation for hypoplastic left heart syndrome, is also applied for other complex single-ventricle lesions with systemic outflow tract obstruction or aortic arch hypoplasia. We reviewed our 15-year institutional experience with the Norwood procedure for patients with and without hypoplastic left heart syndrome.

METHODS

A total of 41 patients without hypoplastic left heart syndrome and 212 patients with hypoplastic left heart syndrome who underwent a Norwood procedure between January 1996 and December 2010 were enrolled. Full medical records were reviewed to assess the determinants of outcome.

RESULTS

Early failure (death or cardiac transplantation) was 7% in patients without hypoplastic left heart syndrome and 13% in patients with hypoplastic left heart syndrome (P = .29). Frequency of postoperative complications, duration of postoperative ventilation, and length of vasoactive drug treatment were not different between groups. Transplant-free survival until the second operative step trended to be higher for patients without hypoplastic left heart syndrome (92% vs 80%, P = .067). Recurrent aortic arch obstruction was more common in patients without hypoplastic left heart syndrome (15/39 vs 32/171, P = .008), but there were 4 patients with stenosis of the proximal aortic arch. In subsequent procedures, 31 patients without hypoplastic left heart syndrome underwent superior cavopulmonary anastomosis and 5 biventricular repair. Overall transplant-free survival was not different between groups (P = .119) but trended to be higher in patients with a systemic or substantial left ventricle remnant contributing to cardiac output (P = .082).

CONCLUSIONS

Early and long-term survivals and postoperative complications were similar between patients with and without hypoplastic left heart syndrome undergoing a Norwood operation. Recurrent aortic arch obstruction was common in both groups but more prevalent in patients without hypoplastic left heart syndrome.

Management of older single functioning ventricles with outlet obstruction due to a restricted "VSD" in double inlet left ventricle and in complex double outlet right ventricle

The occurrence of a restriction of the bulbo-ventricular foramen (BVF) in older patient with double inlet left ventricle (DILV) or tricuspid atresia (TA) with ventriculo-arterial discordance is a well-known condition. Today, the surgical management is to perform a Damus-type operation at the time of the bi-directional Glenn or at the Fontan completion. The ventricular septal defect (VSD) enlargement, associated with muscular resection and a patch enlargement of the subaortic accessory ventricular chamber, is rarely performed but remains indicated in cases with pulmonary valve atresia or regurgitation. This condition is essentially prevented by doing an early Norwood-type operation in the presence of DILV/TA with transposition of the great arteries associated with an aortic arch obstruction. The palliative switch operation is an option that was abandoned because of poor control of the pulmonary blood flow. It is only in cases of large unobstructed BVF that pulmonary artery banding could be undertaken in neonates, followed by close echocardiographic follow-up. The occurrence of a restriction or a closure of the VSD in complex DORV following a Fontan operation is a dramatic event and is quite "new business." It has been recently recognized that the VSD becomes restricted in a number of patients with DORV-nc-VSD treated with a Fontan palliation. This new condition is not surprising knowing that 75% of the VSDs must be enlarged preventively in DORV-nc-VSD repair. In the setting of a Fontan circulation, the supra-systemic left ventricle has severe consequences the right ventricle performance. Attempts at surgical VSD enlargement or catheter-based procedures have resulted in almost constant recurrence. This recently reported complication is in favor of also performing a VSD enlargement at the time of the Fontan completion in complex DORV. It justifies the biventricular repair in complex DORV with two viable ventricles.

Designing therapeutic strategies for patients with a dominant left ventricle, discordant ventriculo-arterial connections, and unobstructed flow of blood to the lungs

The palliation of the cyanotic child with a dominant morphologically left ventricle, discordant ventriculo-arterial connections, and obstruction to the pulmonary outflow tract has continued to evolve and mature. The evolution began in the early days of surgical palliation with the Blalock-Taussig shunt, extended to construction of cavopulmonary shunts, if required, and then to the Fontan procedure and its subsequent modifications. This journey took nearly 30 years to complete. There is increasing clinical data to document the beneficial effects of this approach, with ever-improving outcomes. Some aspects of the history of the cavopulmonary shunt have been previously reviewed in this journal and elsewhere, as have analysis of outcomes for some groups of patients considered for surgical completion of the Fontan circulation. While there has been some ongoing interest in ventricular septation since the early success of Sakakibara et al., this approach has largely been abandoned. Considerably more challenges and debate resonate in the surgical algorithms defined for patients whose hearts are characterized by a dominant left ventricle, discordant ventriculo-arterial connections, and unobstructed flow of blood to the lungs. This latter group will be the focus of this review, as will the aetiology of the myocardial hypertrophy that is particularly frequent in this group of patients, its clinical recognition, indeed its anticipation, and the multiple surgical strategies designed to prevent or treat it. All these manoeuvres are considered to optimise suitability for, and outcome from, creation of the Fontan circulation.

Management of univentricular heart with systemic ventricular outflow obstruction by pulmonary artery banding and Damus-Kaye-Stansel operation

BACKGROUND

Some patients with univentricular hearts who are candidates for Fontan operation may develop ventricular outflow tract obstruction after pulmonary artery banding (PAB) or Fontan. However, the indication for Damus-Kaye-Stansel (DKS) operation for these patients has not been clear. To clarify the indication, the changes in the diameter of ventricular outflow tract and the feasibility of DKS operation before or with Fontan were investigated.

METHODS

Among the patients with univentricular heart who underwent PAB, 21 patients had probable ventricular outflow obstruction with an aorta arising from the morphologic right ventricle. Diameter of ventricular outflow tract was measured before and after PAB, Glenn, and Fontan operations with or without DKS, and indexed by normal value (%VOT).

RESULTS

Six patients died after PAB. In the surviving 15 patients, %VOT decreased significantly from 103% (median, range 75%-153%) to 75% (range 52%-153%) after PAB. Four with very small %VOT (52% to 63%) after PAB needed DKS with bidirectional Glenn or central shunt operation, and 5 with moderately small %VOT (67% to 109%) after PAB needed DKS concomitantly with Fontan. A patient with %VOT of 117% before Fontan required DKS after Fontan. A patient with %VOT of 153% underwent Fontan without DKS and obstruction did not develop after Fontan. The remaining 4 patients were under consideration for Glenn or Fontan operation.

CONCLUSIONS

The diameter of the ventricular outflow tract decreased after PAB and Fontan operations. DKS operations might be indicated before Fontan if the indexed diameter of ventricular outflow tract after PAB was below 70% and concomitantly with Fontan if it was below 120%.

The infant with single ventricle and excessive pulmonary blood flow: results of a strategy of pulmonary artery division and shunt

BACKGROUND

The infant with a single ventricle and excessive pulmonary blood flow requires early protection of the pulmonary vascular bed to insure suitability for a subsequent Fontan procedure. The traditional approach, pulmonary artery banding, has had disappointing results. We have pursued an alternate strategy: division of the pulmonary artery, and placement of a systemic-to-pulmonary artery shunt. Potential sites of systemic outflow tract obstruction are simultaneously bypassed, by either a Damus-Kaye-Stansel, or modified Norwood procedure.

METHODS

From January 1996 to June 2001, 22 infants were treated by this strategy. Patients with hypoplastic left heart syndrome were excluded. Median age was 18 days (range 2 days to 6 months). In addition to pulmonary artery division and shunt, 3 of 22 patients underwent a Damus-Kaye-Stansel procedure, and 13 of 22 patients underwent a modified Norwood procedure.

RESULTS

There were no operative deaths, and one late death. Actuarial survival beyond 30 months was 90%. At follow-up catheterization in 22 patients, median transpulmonary gradient was 7 mmHg (range 4 to 18), and median pulmonary vascular resistance 1.9 Wood units (range 0.9 to 3.3). Twenty-one patients have undergone a subsequent bidirectional superior cavopulmonary connection, and 6 a Fontan procedure, with no deaths. No patient developed subaortic stenosis, or aortic arch obstruction. Neoaortic insufficiency was none or trivial in 12 patients, mild in 3, and moderate in 1.

CONCLUSIONS

In patients with a functional single ventricle and excessive pulmonary flow, a strategy of pulmonary artery division and shunt, along with prophylactic bypass of systemic outflow obstruction, carries low operative and midterm mortality. It provides consistent protection of the pulmonary vascular bed, avoids subaortic stenosis and aortic arch obstruction, minimizes neoaortic insufficiency, and ensures suitability for progression along a Fontan pathway. These results provide a comparison for alternate strategies, including pulmonary artery banding.

Potential goals for the dimensions of the pulmonary arteries and aorta with stenting after the Fontan operation

The purpose of this study was to clarify desired stent sizes for stenotic lesions in the post-Fontan circulation. Using angiograms from 22 patients before and at late follow-up (> or = 15 years) after the Fontan operation, we measured the maximum diameters of the proximal pulmonary arteries (PA) and the descending aorta. The diameters of the PA ipsilateral to the inferior vena cava, contralateral to the inferior vena cava, and descending aorta after the Fontan were 10.6-22.6 (15.8 +/- 3.3), 8.0-19.1 (12.9 +/- 3.1), and 12.1-18.9 (15.8 +/- 2.0) mm, respectively, while the percent of normal predicted diameters (% N) were 55%-104% (70% +/- 14%), 38%-99% (66% +/- 17%), and 46%-74% (60% +/- 7%), respectively. Despite somatic growth, the % N of all vessel diameters decreased significantly after the Fontan operation. In conclusion, smaller-sized stents should be acceptable for both the pulmonary artery and descending aorta in the Fontan circulation.

Single ventricle with systemic obstruction in early life: comparison of initial pulmonary artery banding versus the Norwood operation

OBJECTIVES

The outcomes of initial pulmonary artery banding (PAB)+/-coarctation repair are compared with the Norwood operation in newborns with single ventricle (SV) and systemic obstruction (SO).

METHODS

Between January 1987 and July 2000, 22 patients (median age, 12 days) with SV and aortic arch obstruction (AAO), subaortic stenosis (SAS), or both underwent surgery. Two initial surgical approaches were used: PAB+/-coarctation repair (group I, seven patients); Norwood type operation (group II, 15 patients).

RESULTS

The overall mortality was 32% (seven of 22 patients). There was no late mortality. The mortality in group I was 43% versus 27% in group II. Recently, there has been no mortality following the Norwood operation in the last eight patients operated since 1995. Of the survivors, nine patients have undergone the Fontan operation and four patients have had the bidirectional Glenn (BDG) with no deaths. There was one repair of supravalvar aortic stenosis at the time of BDG in group II as opposed to eight reinterventions for SAS and/or AAO in four patients in group I (P=0.01).

CONCLUSIONS

PAB+/-coarctation repair for SV and SO is associated with a high mortality and a high reoperation rate for SAS or recurrent AAO. Although the Norwood operation was also associated with a high mortality early on, it can now be performed with excellent outcome. This improvement, combined with a low reintervention rate for SAS or AAO, suggests that the Norwood operation is likely to emerge as the procedure of choice for SV and SO.

Damus-Kaye-Stansel connections in children with previously transected pulmonary arteries

BACKGROUND

In patients with a univentricular arteriovenous connection, transection of the main pulmonary artery may be performed as part of a bidirectional cavopulmonary shunt or Fontan procedure. The proximal stump of the pulmonary artery may remain in the systemic circulation. In cases with a discordant ventriculoarterial connection, subsequent restriction of the bulboventricular foramen may lead to subaortic stenosis. The subaortic stenosis can be corrected in some patients by directing the systemic flow through a combined nonobstructed aortopulmonary outlet, as in the Damus-Kaye-Stansel connection. Previous closure of the pulmonary artery has been considered by some investigators to be a relative contraindication to the Damus-Kaye-Stansel procedure, unless an allograft root can be added to the circuit after excision of the closed pulmonary stump.

METHODS

Three patients with previously transected pulmonary arteries underwent a modified Damus-Kaye-Stansel connection using the native pulmonary valve and the proximal pulmonary artery stump.

RESULTS

The native pulmonary valves have functioned well despite thrombus formation in the proximal stump in 2 patients before Damus conversion. All 3 patients are alive and well after 108, 19, and 3 months, with competent nonobstructed ventriculoarterial connections.

CONCLUSIONS

If transection and closure of the pulmonary artery as part of a previous palliation has spared the pulmonary valve, then the native pulmonary outlet might be used for a safe Damus-Kaye-Stansel connection.

Repair of coarctation of the aorta during infancy minimizes the risk of late hypertension

BACKGROUND

Recent surgical reports on coarctation of the aorta have primarily focused on the relative merits of various operative techniques. However, appropriate timing for elective repair remains unclear.

METHODS

In a retrospective analysis we examined the surgical outcomes in 176 consecutive patients undergoing repair of coarctation of the aorta in our institution over a 25-year period. Ninety-nine percent of the patients had follow-up for a median of 7.5 years.

RESULTS

A total of 13 patients have died (7.4% overall mortality). Nine of these patients had associated complex intracardiac anomalies. There was no mortality in the 113 patients with isolated coarctation. Residual or recurrent coarctation occurred in 27 patients (15.3%). The age at operation and the type of surgical repair did not have an effect on the incidence of recurrence. Persistent or late hypertension was identified in 18 of the 107 patients who have been followed up for more than 5 years (16.8%). A total of 48 patients operated on during infancy have been followed up for more than 5 years. Only 2 have developed late hypertension (4.2%). Both of these patients had recurrence. In contrast, 16 of the 59 patients operated on after a year of age had late hypertension (27.1%).

CONCLUSIONS

To minimize the risk of persistent hypertension, elective repair of coarctation should be performed within the first year of life.

Does banding the pulmonary artery affect pulmonary valve function after the Damus-Kaye-Stansel operation?

BACKGROUND

The Damus-Kaye-Stansel (DKS) operation can be an effective palliation in patients who have single-ventricle physiology and systemic outflow obstruction. Pulmonary artery banding (PAB) may be used as a preliminary procedure in these patients to limit overperfusion of the pulmonary circulation. In some series, the DKS operation has been associated with pulmonary insufficiency (PI). We retrospectively analyzed medical records of our patients who had PAB and later DKS to determine the incidence of PI in these patients.

METHODS

Between 1982 and 1996, 15 patients underwent PAB before DKS. Median age at PAB placement was 7 days and median duration of PAB was 7 months. Echocardiograms obtained before PAB, before DKS, and at the most recent post-DKS follow-up were reviewed.

RESULTS

Follow-up ranged from 1 to 15 years (mean follow-up, 7.5 years). One patient had trivial PI before PAB, which progressed to moderate PI at the last follow-up. Only 1 other patient had mild PI, but only at the last follow-up after DKS.

CONCLUSIONS

These findings suggest that prior PAB does not appear to cause significant PI in patients slated for DKS, and the incidence of significant PI after the DKS operation is relatively low.

Subaortic obstruction and the Fontan operation

Systemic outflow tract obstruction in the heart with a functional single ventricle promotes myocardial hypertrophy, and this has been shown to be an unequivocal risk factor for poor outcome at Fontan procedure. Such systemic outflow tract obstruction may be congenital or acquired. Those factors contributing to acquired systemic outflow tract obstruction in those patients with a double-inlet left ventricle, a rudimentary right ventricle, and a discordant ventriculoarterial connection include the size of the ventricular septal defect, previous pulmonary artery banding, and other volume unloading surgical procedures. Staging with a bidirectional cavopulmonary connection and construction of a proximal pulmonary artery-aortic connection or ventricular septal defect enlargement has neutralized this factor.

Modified Damus-Kaye-Stansel procedure for single ventricle, subaortic stenosis, and arch obstruction in neonates and infants: midterm results and techniques for avoiding circulatory arrest

BACKGROUND

A modified Damus-Kaye-Stansel procedure is one of several options for palliation of single ventricle with subaortic obstruction, but results in neonates have been disappointing. In the presence of arch obstruction, this procedure is typically performed with circulatory arrest, which may contribute to neurologic insult.

METHODS

Since 1990, a modified Damus-Kaye-Stansel procedure has been performed in 14 neonates and seven infants with single ventricle and subaortic stenosis, including 15 with arch obstruction. Diagnoses were double-inlet left ventricle (n = 12), tricuspid atresia (n = 2), and other forms of hypoplastic ventricle with subaortic obstruction (n = 7). Three patients underwent concurrent bidirectional Glenn shunt. In the most recent seven patients with arch obstruction, arch repair was achieved with an end-to-side anastomosis of the descending aorta to the ascending aorta with continuous upper body perfusion.

RESULTS

One early death occurred among the 14 neonates (7%) and three among the infants, for an early mortality of 19%. At a median follow-up of 33 months, there were no late deaths or neurologic complications. Nine patients underwent subsequent bidirectional Glenn anastomosis, including three who had Fontan completion and one who later underwent conversion to a partial biventricular repair. One patient required a transplant for cardiomyopathy of unknown etiology. The remaining 12 patients are considered good candidates for Fontan completion. No patient has recurrent arch obstruction. Four patients have mild (n = 1) or trivial (n = 3) semilunar valvular regurgitation.

CONCLUSION

The modified Damus-Kaye-Stansel procedure is an effective primary palliation for single ventricle and subaortic stenosis, with or without arch obstruction. Results are especially encouraging in neonates. Arch repair can be achieved without circulatory arrest to the brain.

Allograft root on closed pulmonary valve for subaortic obstruction in double-inlet left ventricle with transposition of the great arteries

BACKGROUND

Until recently closure of the pulmonary valve during staged Fontan-type palliation in the setting of double-inlet left ventricle with an unrestrictive or adequately enlarged ventricular septal defect and transposition of the great arteries with the aorta on a left-sided outflow chamber was regarded as an appropriate part of surgical treatment. Lately, however, an increased incidence of subsequent subaortic obstruction has been described in this regard.

METHODS

Allograft root placement on the previously closed pulmonary orifice in combination with a modified Damus-Kaye-Stansel procedure is described to create an unobstructed outflow from the main ventricle to the systemic circulation. This procedure was done in 3 patients. One root placement was combined with the construction of the bidirectional superior cavopulmonary connection, one was done as an intermediate step before completion of the cavopulmonary connection, and one was combined with completion of total cavopulmonary connection.

RESULTS

Immediate relief of the subaortic obstruction was achieved in all 3 patients. Ventricular hypertrophy, echocardiographically assessed by diastolic posterior wall thickness, regressed to normal in all 3 within 6 to 12 months.

CONCLUSIONS

Allograft root placement on the reopened pulmonary orifice in double-inlet left ventricle with a ventricular septal defect and transposition of the great arteries appears technically feasible and functionally adequate on short-term follow-up. This procedure should result in regression of ventricular hypertrophy to allow eligibility for a Fontan-type palliation again. To what extent possible failure of the allograft increases the risk of an adverse outcome of this palliation may be a matter of concern.

Repair of interrupted aortic arch: a ten-year experience

Eighty-two consecutive patients with interrupted aortic arch were referred to our institution between 1985 and 1995. Three died before any attempt at operation and 79 underwent surgical repair. Median age at operation was 9 days (range 1 day to 6 years) and median weight was 3.0 kg (range 1.8 to 20 kg). All but one were in severe congestive heart failure and 31.5% had oliguria or anuria. Preoperative pH varied between 6.8 and 7.4 (median 7.3). Sixty-nine received prostaglandin E1 infusion and 54 received mechanical ventilation. Aggressive preoperative ressucitation was necessary in 43 cases. Preoperative transfontanellar echography (performed routinely) since 1987 revealed intracerebral bleeding in six patients. Type A interrupted aortic arch was present in 37 cases, 41 patients had type B, and one had type C. Interrupted aortic arch was associated with single ventricular septal defect in 35 cases, 24 patients had associated complex heart defects, and 30 had significant subaortic stenosis (six had both subaortic stenosis and complex association). Aortopulmonary window was found in four patients, truncus arteriosus was found in eight, and transposition of the great arteries was found in five, double-outlet right ventricle was found in one, single ventricle was found in three, multiple ventricular septal defects were found in two and superior-inferior ventricles were found in one. Sixty-four patients underwent single-stage repair and 15 underwent multistage repair. Aortic arch repair consisted of direct anastomosis in 59 cases, patch augmentation in eight, and conduit interposition in 12. Ten patients underwent associated pulmonary artery banding and 19 underwent concomitant repair of complex associated lesions. The subaortic stenosis was addressed by four surgical techniques: myotomy or myectomy in five patients; creation of a double-outlet left ventricle, aortopulmonary anastomosis, and conduit insertion between the right ventricle and pulmonary artery bifurcation in four; no direct attempt to relieve the subaortic stenosis in six; and left-sided ventricular septal defect patch in 15. Mean duration of deep hypothermic circulatory arrest, crossclamp time, and cardiopulmonary bypass time were 38.8 +/- 15.6 min, 60.5 +/- 24.7 min, and 143 +/- 40.1 min, respectively. Postoperative mortality rate was 18.9% (70% confidence limits 14% to 24.6%), and overall mortality rate was 31% (70% confidence limits 20.9% to 42.2%). The results have improved with time, with an overall operative mortality rate of 12% since 1990. Univariate statistical analysis revealed that early survival was influenced by preoperative renal function, detection of cerebral bleeding by transfontanellar echography, the number of cardioplegic injections, and the date of operation. Multivariate analysis revealed that preoperative renal function and the number of cardioplegic injections were independent risk factors for early mortality. Echocardiographic measurements of the left heart-aorta complex with preoperative Z values as low as-4 demonstrated rapid growth after repair. In the presence of subaortic stenosis, better survival was obtained with a left-sided patch for ventricular septal defect closure (p < 0.05). Twenty-three patients underwent 26 reoperations for recoarctations (seven), left bronchial compression (two), second-stage repair (eight), right ventricle-pulmonary artery conduit replacement (three), and miscellaneous (four). One of the survivors was reoperated on for subaortic membrane. Survival at 5 years for the entire series was 70%. For isolated forms, it was 73.5% (90% for 1990 to 1995), for complex forms it was 70%, and in the presence of subaortic stenosis it was 60%. In conclusion, interrupted aortic arch remains a surgical challenge with continually improving results. Early diagnosis with preoperative resuscitation and adequate myocardial protection seem extremely important for further improvements. Associated subaortic stenosis or complex lesions