Differential branch pulmonary artery growth after the Norwood procedure with right ventricle–pulmonary artery conduit versus modified Blalock–Taussig shunt in hypoplastic left heart syndrome

Norwood Operation with Right Ventricular-Pulmonary Artery Shunt Versus Comprehensive Stage II After Bilateral Pulmonary Artery Banding Palliation

As a strategy for the primary Norwood operation, the right ventricular-pulmonary artery shunt is associated with satisfactory early outcome. However, use of this shunt after bilateral pulmonary artery banding remains controversial. This study compared the operative outcomes and late hemodynamics in patients who underwent the Norwood operation, preceded by bilateral pulmonary artery banding, with a right ventricular-pulmonary artery shunt or with bidirectional Glenn anastomosis (comprehensive stage II strategy). We retrospectively reviewed 38 patients who underwent the Norwood operation preceded by bilateral pulmonary artery banding between 2004 and 2017. Of these, 17 underwent the Norwood operation with a right ventricular-pulmonary artery shunt (Group S), whereas 21 underwent the comprehensive stage II strategy (Group G). 5 years after the Norwood operation, 10 (60%) and 17 (81%) patients in Group S and Group G, respectively, underwent the Fontan procedure. Group S showed significantly lower pressure in the superior vena cava after bidirectional Glenn anastomosis than Group G (13 ± 2 mmHg vs. 18 ± 3 mmHg; p < 0.01), but pressures were similar after the Fontan procedure. The right ventricular end-diastolic volume at 1 year post-Fontan procedure was significantly higher in Group S than in Group G (142 ± 41% vs. 91 ± 28%; p < 0.01). In terms of early outcomes, the Norwood operation with a right ventricular-pulmonary artery shunt enabled low pressure in the superior vena cava, but in the long term, this shunt adversely influenced the right ventricular volume.

Surgical pulmonary arterioplasty at bidirectional cavopulmonary anastomosis leads to favorable pulmonary hemodynamics at final stage palliation

Objective

Pulmonary arterioplasty (PA plasty) at bidirectional cavopulmonary anastomosis (BDCA) is associated with increased morbidity, but outcomes to final stage palliation are unknown. We sought to determine the influence of PA plasty on pulmonary artery growth and hemodyamics at Fontan.

Methods

We retrospectively reviewed clinical data and outcomes for BDCA patients from 2006 to 2018. PA plasty was categorized by extent (type 1-4), as previously described. Outcomes included pulmonary artery reintervention and mortality before final palliation.

Results

Five hundred eighty-eight patients underwent BDCA. One hundred seventy-nine patients (30.0%) underwent concomitant PA plasty. Five hundred seventy (97%) patients (169 [94%] PA plasty) survived to BDCA discharge. One hundred forty out of 570 survivors (25%) required PA/Glenn reintervention before final stage palliation (59 out of 169 [35%]) PA plasty; 81 out of 401 (20%) non-PA plasty; P < .001). Twelve-, 24-, and 36-month freedom from reintervention after BDCA was 80% (95% CI, 74-86%), 75% (95% CI, 69-82%), and 64% (95% CI, 57-73%) for PA plasty, and 95% (95% CI, 93-97%), 91% (95% CI, 88-94%), and 81% (95% CI, 76-85%) for non-PA plasty (P < .001). Prefinal stage mortality was 37 (6.3%) (14 out of 169 PA plasty; 23 out of 401 non-PA plasty; P = .4). Five hundred four (144 PA plasty and 360 non-PA plasty) patients reached final stage palliation (471 Fontan, 26 1.5-ventricle, and 7 2-ventricular repair). Pre-Fontan PA pressure and pulmonary vascular resistance were 10 mm Hg (range, 9-12 mm Hg) and 1.6 mm Hg (range, 1.3-1.9 mm Hg) in PA plasty and 10 mm Hg (range, 8-12 mm Hg) and 1.5 mm Hg (range, 1.3-1.9 mm Hg) in non-PA plasty patients, respectively (P = .29, .6). Fontan hospital mortality, length of stay, and morbidity were similar.

Conclusions

PA plasty at BDCA does not confer additional mortality risk leading to final palliation. Despite increased pulmonary artery reintervention, there was reliable pulmonary artery growth and favorable pulmonary hemodynamics at final stage palliation.

Surgical Modulation of Pulmonary Artery Shear Stress: A Patient-Specific CFD Analysis of the Norwood Procedure

PURPOSR

This study created 3D CFD models of the Norwood procedure for hypoplastic left heart syndrome (HLHS) using standard angiography and echocardiogram data to investigate the impact of shunt characteristics on pulmonary artery (PA) hemodynamics. Leveraging routine clinical data offers advantages such as availability and cost-effectiveness without subjecting patients to additional invasive procedures.

METHODS

Patient-specific geometries of the intrathoracic arteries of two Norwood patients were generated from biplane cineangiograms. "Virtual surgery" was then performed to simulate the hemodynamics of alternative PA shunt configurations, including shunt type (modified Blalock-Thomas-Taussig shunt (mBTTS) vs. right ventricle-to-pulmonary artery shunt (RVPAS)), shunt diameter, and pulmonary artery anastomosis angle. Left-right pulmonary flow differential, Qp/Qs, time-averaged wall shear stress (TAWSS), and oscillatory shear index (OSI) were evaluated.

RESULTS

There was strong agreement between clinically measured data and CFD model output throughout the patient-specific models. Geometries with a RVPAS tended toward more balanced left-right pulmonary flow, lower Qp/Qs, and greater TAWSS and OSI than models with a mBTTS. For both shunt types, larger shunts resulted in a higher Qp/Qs and higher TAWSS, with minimal effect on OSI. Low TAWSS areas correlated with regions of low flow and changing the PA-shunt anastomosis angle to face toward low TAWSS regions increased TAWSS.

CONCLUSION

Excellent correlation between clinically measured and CFD model data shows that 3D CFD models of HLHS Norwood can be developed using standard angiography and echocardiographic data. The CFD analysis also revealed consistent changes in PA TAWSS, flow differential, and OSI as a function of shunt characteristics.

Current status of transcatheter intervention for complex right ventricular outflow tract abnormalities

Various transcatheter interventions for the right ventricular outflow tract (RVOT) have been introduced and developed in recent decades. Transcatheter pulmonary valve perforation was first introduced in the 1990s. Radiofrequency wire perforation has been the approach of choice for membranous pulmonary atresia in newborns, with high success rates, although complication rates remain relatively common. Stenting of the RVOT is a novel palliative treatment that may improve hemodynamics in neonatal patients with reduced pulmonary blood flow and RVOT obstruction. Whether this option is superior to other surgical palliative strategies or early primary repair of tetralogy of Fallot remains unclear. Transcatheter pulmonary valve replacement has been one of the biggest innovations in the last two decades. With the success of the Melody and SAPIEN valves, this technique has evolved into the gold standard therapy for RVOT abnormalities with excellent procedural safety and efficacy. Challenges remain in managing the wide heterogeneity of postoperative lesions seen in RVOT, and various technical modifications, such as pre-stenting, valve ring modification, or development of self-expanding systems, have been made. Recent large studies have revealed outcomes comparable to those of surgery, with less morbidity. Further experience and multicenter studies and registries to compare the outcomes of various strategies are necessary, with the ultimate goal of a single-step, minimally invasive approach offering the best longer-term anatomical and physiological results.

Factors affecting the outcomes after bidirectional Glenn shunt: two decades of experience from a tertiary referral center

BACKGROUND

Despite the improved management of patients with a single ventricle, the long-term outcomes are not optimal. We reported the outcomes of the bidirectional Glenn procedure (BDG) and factors affecting the length of hospital stay, operative mortality, and Nakata index before Fontan completion.

RESULTS

This retrospective study included 259 patients who underwent BDG shunt from 2002 to 2020. The primary study outcomes were operative mortality, duration of hospital stay, and Nakata index before Fontan. Mortality occurred in 10 patients after BDG shunt (3.86%). By univariable logistic regression analysis, postoperative mortality after BDG shunt was associated with high preoperative mean pulmonary artery pressure (OR: 1.06 (95% CI 1.01-1.23); P = 0.02). The median duration of hospital stay after BDG shunt was 12 (9-19) days. Multivariable analysis indicated that Norwood palliation before BDG shunt was significantly associated with prolonged hospital stay (β: 0.53 (95% CI 0.12-0.95), P = 0.01). Fontan completion was performed in 144 patients (50.03%), and the pre-Fontan Nataka index was 173 (130.92-225.34) mm²/m². Norwood palliation (β: - 0.61 (95% CI 62.63-20.18), P = 0.003) and preoperative saturation (β: - 2.38 (95% CI - 4.49-0.26), P = 0.03) were inversely associated with pre-Fontan Nakata index in patients who had Fontan completion.

CONCLUSIONS

BDG had a low mortality rate. Pulmonary artery pressure, Norwood palliation, cardiopulmonary bypass time, and pre-BDG shunt saturation were key factors associated with post-BDG outcomes in our series.

Decellularized vs Non-decellularized Allogeneic Pulmonary Artery Patches for Pulmonary Arterioplasty

We studied pulmonary artery size, reinterventions, and panel reactive antibodies in patients with single-ventricle physiology who underwent a pulmonary arterioplasty with decellularized (DAPAP) and non-decellularized allogeneic pulmonary artery patches (non-DAPAP). Retrospective review identified 59 patients with single-ventricle physiology who underwent pulmonary arterioplasty from 2008 to 2017: 28 patients underwent arterioplasty with DAPAP and 31 patients with non-DAPAP. Demographic and operative variables were similar between groups. Among patients who underwent a Norwood procedure, a right ventricle to pulmonary artery shunt was more commonly used in the DAPAP group (12/20, 60%) and a modified Blalock-Taussig shunt was more commonly used in the non-DAPAP group (17/22, 77%). On multivariable analysis, the use of DAPAP was associated with higher pre-Fontan angiography Z-scores in right (estimate = 0.17, standard error = 0.04, P = 0.0005) and left pulmonary arteries (estimate = 0.12, standard error = 0.05, P = 0.01). No areas of calcification, discrete coarctation, or pulmonary dilation were noted in any of the pulmonary arteries. On multivariable analysis, the use of DAPAP was associated with higher freedom from pulmonary artery reinterventions (Hazard ratio = 0.36, 95% confidence interval = 0.13-0.9, P = 0.04). The median value for Class I panel reactive antibodies was 0% (IQR 0, 4) in the DAPAP and 23% (IQR 14, 36) in the non-DAPAP group. The median value for Class II panel reactive antibodies was 15% (IQR 0, 17) in the DAPAP and 21% (IQR 10, 22) in the non-DAPAP group. Pulmonary arterioplasty with DAPAP was associated with higher pre-Fontan pulmonary artery Z-scores and higher freedom from pulmonary artery reinterventions.

Influence of Shunt Type on Survival and Right Heart Function after the Norwood Procedure for Aortic Atresia

The study objective was to compare the results after Norwood procedure between modified Blalock-Taussig shunt (MBTS) and right ventricle-to-pulmonary artery conduit (RVPAC) according to Sano in patients with hypoplastic left heart syndrome (HLHS) and aortic atresia (AA). A total of 146 neonates with HLHS and AA who underwent the Norwood procedure at our institution between 2001 and 2020 were divided into 2 groups according to shunt type (MBTS or RVPAC). Survival after the Norwood procedure was compared between the groups. Longitudinal right ventricular and tricuspid valve function in each group were evaluated using cubic splines method. RVPAC was performed in 103 patients and MBTS in 43 according to surgeon preference. There were no differences in the 30-day mortality rates (16.5% vs 16.3%, P  = 0.973). Survival at 0.5, 1 and 3 years was 79.6%, 74.6%, and 68.9% in RVPAC and 66.8%, 64.3%, and 58.5% in MBTS (P  =  0.293). Among 23 patients undergoing tricuspid valve procedure, different mechanisms of tricuspid regurgitation were observed between the groups. Longitudinal analysis revealed greater prevalence of late right ventricular dysfunction in RVPAC patients. In 77 patients who completed Fontan procedure, the postoperative N-terminal pro B-type natriuretic peptide value was significantly higher in RVPAC vs MBTS (554 vs 276 ng/L, P  =  0.007). No survival advantage of RVPAC over MBTS was observed in neonates with HLHS and AA undergoing the Norwood procedure. Longitudinal analysis demonstrated a greater prevalence of right ventricular dysfunction and higher N-terminal pro B-type natriuretic peptide values during late follow-up in patients with RVPAC.

Comparison of shunt types in the neonatal Norwood procedure for single ventricle

OBJECTIVES

The ideal shunt for pulmonary blood flow, modified Blalock-Taussig shunt (MBTS) or right ventricular-pulmonary artery conduit (RVPAC) is yet to be determined. This study aimed to evaluate outcomes after the Norwood procedure according to the type of shunt.

METHODS

A total of 322 neonates with hypoplastic left heart syndrome and related anomalies who underwent the Norwood procedure at our institution between 2001 and 2019 were divided into MBTS and RVPAC groups and the outcomes after the Norwood procedure were compared between the groups with respect to mortality after each staged procedure.

RESULTS

We identified 322 consequent patients who underwent neonatal Norwood procedure for hypoplastic left heart syndrome (271 patients, 84.2%) and its variant (51 patients, 15.8%). RVPAC was performed in 163 (50.6%) patients and MBTS was performed in 159 (49.4%). There were no differences in the rate of early death (11.0% vs 12.6%, P = 0.69) or late death (7.4% vs 6.9%, P = 0.87) between the 2 groups after the Norwood procedure, and no significant difference in the number of patients who reached bidirectional cavopulmonary shunt (77.9% vs 76.1%, P = 0.69), and there was no difference in mortality after bidirectional cavopulmonary shunt (12.3% vs 7.5%, P = 0.15) or Fontan completion rate (54.0% vs 52.2%, P = 0.42) between the 2 groups. Survival at 0.5, 1, 3 and 6 years after the Norwood procedure was 81.0%, 73.8%, 67.9% and 67.0% in patients with RVPAC and 77.1%, 73.3%, 69.1% and 67.9% in patients with MBTS. There was no significant difference in the survival between the 2 groups during the median follow-up of 2.6 (interquartile ranges: 0.3-8.4, maximal 18.8) years (P = 0.97).

CONCLUSIONS

In neonates undergoing the Norwood procedure, our available data of maximal 18.8 years follow-up showed no significant difference in early mortality, inter-stage attritions, or overall survival, between MBTS and RVPAC.

Right Ventricular Outflow Tract Stenting as Palliation of Critical Tetralogy of Fallot: Techniques and Results

Background. Despite current trends toward early primary repair, the surgical systemic-to-pulmonary shunt is still considered the first-choice palliation in patients with critical tetralogy of Fallot (TOF) and duct-dependent pulmonary circulation unsuitable for primary repair. However, stenting of the right ventricular outflow tract (RVOT) is nowadays emerging as an effective alternative to surgical palliation in selected patients. Methods and results. RVOT stenting is usually performed from a venous route, either femoral or, in selected cases, the right internal jugular vein. Less frequently, mostly in pulmonary infundibular/valvar atresia, this procedure can be performed using a hybrid surgical/interventional approach by surgical exposure of the RVOT, puncture of the atretic valve, and stent deployment under direct vision. The size and type of the most appropriate stent may be chosen, based on ultrasound measurements of the RVOT, to cover the right ventricular infundibulum completely and, at the same time, sparing the pulmonary valve, unless significant pulmonary valve annulus hypoplasia and/or supra-valvular stenosis is a significant component of the obstruction. In the large series so far published, early mortality of RVOT stenting is less than 2%, comparing favourably with either Blalock-Thomas-Taussig shunt or early primary repair. In addition, morbidity and clinical sequelae of this approach do not significantly differ from surgical palliation, even if RVOT stenting shows lesser durability and a higher rate of trans-catheter re-interventions over a mid-term follow-up. Finally, similar but more balanced pulmonary artery growth than surgical palliation following RVOT stenting is reported over a mid-term follow-up. Conclusions. RVOT stenting is a technically feasible, well-tolerated, and effective palliation in critical TOF. This approach is cost-effective with respect to surgical palliation either in high-risk neonates or whenever a short-term pulmonary blood flow source is anticipated due to the early surgical repair. It effectively increases pulmonary blood flow, improves arterial saturation, and promotes balanced pulmonary artery growth over a mid-term follow-up.

Pulmonary artery and lung parenchymal growth following early versus delayed stent interventions in a swine pulmonary artery stenosis model

OBJECTIVES

Compare lung parenchymal and pulmonary artery (PA) growth and hemodynamics following early and delayed PA stent interventions for treatment of unilateral branch PA stenosis (PAS) in swine.

BACKGROUND

How the pulmonary circulation remodels in response to different durations of hypoperfusion and how much growth and function can be recovered with catheter directed interventions at differing time periods of lung development is not understood.

METHODS

A total of 18 swine were assigned to four groups: Sham (n = 4), untreated left PAS (LPAS) (n = 4), early intervention (EI) (n = 5), and delayed intervention (DI) (n = 5). EI had left pulmonary artery (LPA) stenting at 5 weeks (6 kg) with redilation at 10 weeks. DI had stenting at 10 weeks. All underwent right heart catheterization, computed tomography, magnetic resonance imaging, and histology at 20 weeks (55 kg).

RESULTS

EI decreased the extent of histologic changes in the left lung as DI had marked alveolar septal and bronchovascular abnormalities (p = .05 and p < .05 vs. sham) that were less prevalent in EI. EI also increased left lung volumes and alveolar counts compared to DI. EI and DI equally restored LPA pulsatility, R heart pressures, and distal LPA growth. EI and DI improved, but did not normalize LPA stenosis diameter (LPA/DAo ratio: Sham 1.27 ± 0.11 mm/mm, DI 0.88 ± 0.10 mm/mm, EI 1.01 ± 0.09 mm/mm) and pulmonary blood flow distributions (LPA-flow%: Sham 52 ± 5%, LPAS 7 ± 2%, DI 44 ± 3%, EI 40 ± 2%).

CONCLUSION

In this surgically created PAS model, EI was associated with improved lung parenchymal development compared to DI. Longer durations of L lung hypoperfusion did not detrimentally affect PA growth and R heart hemodynamics. Functional and anatomical discrepancies persist despite successful stent interventions that warrant additional investigation.

Pulmonary atresia with ventricular septal defect and tetralogy of Fallot: transannular path augmentation versus systemic to pulmonary artery shunt for first-stage palliation

BACKGROUND

Pulmonary atresia with ventricular septal defect and severe tetralogy of Fallot require a palliative procedure for pulmonary artery rehabilitation. For first-stage palliation, two main surgical options are still debated: right ventricle to pulmonary artery connection and modified Blalock-Taussig shunt. We compared the clinical outcomes of the two procedures.

METHODS

From 1995 to 2018, 88 patients needed palliation (pulmonary atresia with ventricular septal defect n = 47; tetralogy of Fallot n = 41). Among these patients, 70 modified Blalock-Taussig shunt and 18 transannular path augmentation were performed before 6 months of age. Using a 1:1 propensity score match analysis, 20 patients were included in the analysis. The primary outcome was in-hospital mortality and pulmonary artery growth.

RESULTS

After matching, the pre-operative Nakata was smaller in transannular path augmentation 54 ± 24 mm2/m2 than modified Blalock-Taussig shunt 109 ± 31 mm2/m2 (p < 0.001). The age and weight were similar (p = 0.31 and p = 0.9, respectively). There was no difference in in-hospital mortality (p = 0.3). The Nakata index before biventricular repair and delta Nakata were smaller in modified Blalock-Taussig shunt group (206 ± 80 mm2/m2, 75 ± 103 mm2/m2) than transannular path augmentation (365 ± 170 mm2/m2, 214 ± 165 mm2/m2; p = 0.03; p < 0.001). Median time to biventricular repair was similar (p = 0.46). The rate of interstage reintervention was similar (p = 0.63).

CONCLUSIONS

The transannular path augmentation is better for the rehabilitation of the native pulmonary artery. Despite a smaller pulmonary artery, right ventricle to pulmonary artery connection is equivalent to modified Blalock-Taussig shunt for rate of biventricular repair and time to biventricular repair.

Cobra-Head Cuffed Vascular Graft as Right Ventricle-to-Pulmonary Artery Shunt in Norwood Procedure

BACKGROUND

Right ventricle-to-pulmonary artery (RV-PA) shunt as a part of the Norwood procedure underwent many modifications. We present our experience with a commercially available polytetrafluoroethylene vascular graft with cobra-head cuff as an RV-PA shunt.

METHODS

A consecutive series of 52 children with hypoplastic left heart syndrome (median age 8 [range, 2-68] days, median weight 3200 [range, 2060-4400] g) underwent the Norwood procedure with a cobra-head cuffed RV-PA shunt (6 mm). The cuffed end was used for the central PA reconstruction. A retrospective analysis of clinical results, PAs development, and shunt-related complications, interventions, and technique of Glenn operation was performed. The study endpoint was Glenn operation with shunt removal or interstage death.

RESULTS

The hospital and late interstage mortality was 3.8% (n = 2 of 52) and 4% (n = 2 of 50), respectively, and was not shunt-related. During mean follow of 3.7 ± 2.5 years, 48 (92.3%) children underwent Glenn operation at a median age of 6 (range, 2.6-9.1) months. Angiography before the second stage revealed satisfactory branch PAs development (maximum and minimum McGoon ratio of 1.95 ± 0.36 and 1.38 ± 0.38, respectively). The mean maximal diameter of the left PA was smaller than that of the right PA (7.13 ± 2.1 mm vs 8.42 ± 2.2 mm; P = .017), without differences in mean minimal diameter. Two infants required stent implantation in proximal shunt end and 1 required urgent Glenn operation because distal shunt thrombosis. During Glenn operation, 11 (22.9%) children required patch reconstruction of central PAs.

CONCLUSIONS

The cobra-head cuffed graft allowed easy and reproducible reconstruction of the central PA during the Norwood procedure. Using this technique, the development of PAs is satisfactory, the rate of shunt-related complications and interventions is low, and the second stage can be performed without patch material.

Recurrent Pulmonary Artery Interventions Following the Norwood Procedure Are Not Associated With Conduit Type

Given pulmonary artery interventions following the Norwood procedure can recur, the average number of occurrences per patient over time is likely more informative than the crude percentage of patients who required an intervention. Pulmonary artery intervention was defined as any surgical or catheter-based procedure after the Norwood procedure. The number of pulmonary artery interventions for patients with hypoplastic left heart syndrome were compared between patients with modified Blalock-Taussig Shunts (MBTS) and right ventricle-to-pulmonary artery conduits (RVPA) at a single institution from 2011 to 2018. The comparison was replicated using data from the Single Ventricle Reconstruction Trial (SVR), a nonoverlapping dataset. The mean number of pulmonary artery interventions per patient over time (mean cumulative function, MCF) is described using Nelson-Aalen estimates and compared using the pseudo-score test. The number of patients requiring intervention was compared using the chi-square test. Using our institutional dataset, the Norwood operation was performed on 117 patients (59 MBTS, 58 RVPA). In total, 73 patients had a pulmonary artery intervention, including 32 of 58 (55%) after MBTS and 41 of 59 (69%) after RVPA (P= 0.11). The MCF did not vary between cohorts (P = 0.55). Using the SVR trial dataset, 140 of 549 patients required pulmonary artery intervention, including 55 (21%) after MBTS and 85 (30%) after RVPA (P = 0.0090). The MCF did not vary between cohorts (P = 0.067). Although more patients with RVPA than MBTS require pulmonary artery interventions after the Norwood procedure, the MCFs are not different, which may be of greater importance to patients and families.

Choice of shunt type for the Norwood I procedure: does it make a difference?

OBJECTIVES

This study aimed to compare pulmonary artery (PA) growth between patients who received a right ventricle-to-PA (RV-PA) shunt and those who received a modified Blalock-Taussig shunt (mBTS).

METHODS

All consecutive patients with hypoplastic left heart syndrome who underwent the Norwood I procedure between 2001 and 2017 were included in the study. Pre-stage 2 angiograms were analysed to measure the size of the PA. The Nakata index was calculated to estimate PA growth. The ratio of the right PA to left PA cross-sectional area (RPA/LPA) was used to calculate the difference in growth between the 2 branches. Study end points were shunt failure, shunt-related mortality and growth of the PAs.

RESULTS

A total of 223 patients with hypoplastic left heart syndrome (RV-PA group = 137, mBTS group = 86) underwent the Norwood I procedure, and 186 patients (RV-PA n = 116, mBTS n = 70) achieved the stage 2 procedure. PA growth was better in patients with mBTS (Nakata index: RV-PA = 282, mBTS = 315 mm2/m2, P = 0.021). LPA growth was worse compared to RPA growth in both groups (RPA/LPA: RV-PA = 1.21, mBTS = 1.29, P = 1.0). Patients with RV-PA shunts experienced more frequent shunt stenosis compared to patients with mBTS (26 vs 2, P < 0.010). Freedom from shunt failure was 83.3 ± 3.2% and 94 ± 2% at 6 months in the RV-PA and mBTS groups, respectively (P = 0.003).

CONCLUSIONS

PA growth is significantly better in patients who received an mBTS. Moreover, patients with an RV-PA shunt more frequently experienced shunt failure due to shunt stenosis. However, survival after the NW procedure is not shunt dependent and growth of the LPA is less pronounced than RPA, regardless of the shunt type.

The effect of a valved small conduit on systemic ventricle–pulmonary artery shunt in the Norwood-type palliation

OBJECTIVES

The aim of this study was to clarify the impact of valved systemic ventricle–pulmonary artery (SV–PA) shunt on outcomes after stage-1 Norwood-type palliation (NP) compared with the modified Blalock–Taussig shunt.

METHODS

Consecutive patients who underwent NP between 2003 and 2019 were enrolled. SV–PA shunts using the expanded polytetrafluoroethylene valved conduit were implanted in 18 patients (valved SV–PA group), and another 18 patients underwent modified Blalock–Taussig shunt during NP (modified Blalock–Taussig shunt group). All valved conduits were made in our institution in advance.

RESULTS

No differences in baseline characteristics were found between the groups, except for shunt size. During a median 2.9 (interquartile range 0.4–6.4, maximum 14.2) years of follow-up, 8 (22.2%) patients died across both groups. There were no statistically significant differences in early mortality (5.5% vs 11.1%, P = 0.55) and overall survival rates at 5 years (80.8% vs 71.4%, P = 0.48) in the valved SV–PA and modified Blalock–Taussig shunt groups. No statistically significant difference was observed in the frequency of interventions between the groups (31% vs 33%, P = 1.0). At the time of the bidirectional Glenn procedure, the systemic ventricular end-diastolic volume index was significantly lower (84 ± 24 vs 106 ± 31 ml/m2, P = 0.05) and the ejection fraction was significantly greater (62 ± 8% vs 55 ± 9%, P = 0.03) in the valved SV–PA group. There was no statistically significant difference in the pulmonary artery index (228 ± 85 vs 226 ± 60 mm2/m2, P = 0.92).

CONCLUSIONS

A valved SV–PA shunt using an expanded polytetrafluoroethylene valved conduit was associated with preserved ventricular function after NP and did not impair pulmonary artery growth by controlling pulmonary regurgitation.

Mid-Term Outcome of Right Ventricle to Pulmonary Artery Shunt for Older Children and Young Adults With Ventricular Septal Defect, Pulmonary Atresia, and Hypoplastic Pulmonary Arteries

Management strategy for patients of ventricular septal defect and pulmonary atresia (VSD/PA) with hypoplastic pulmonary arteries presenting in late childhood or adolescence is still controversial. We present our experience with the use of right ventricle-pulmonary artery shunt (RV-PA) in management of this entity. Between January 2014 and April 2018, 25 patients of VSD/PA underwent valveless RV-PA shunt at our center. The size of the RV to PA shunt was calculated as half the expected diameter of the main pulmonary artery. We retrospectively reviewed the data from hospital records. Follow-up data were recorded from outpatient records or via telephone. Mean age of the cohort was 12.25 ± 3.18 years. There was 1 early and 1 interstage mortality. None of the patient developed acute renal failure, ventricular dysfunction, and arrhythmias. At interstage follow-up of 8.28 ± 3.7 months, both Nakata index (from 66.23 ± 24.12 to 185.8 ± 58 mm²/m²) and McGoon ratio (0.9 ± 0.22 vs 49 1.84 ± 0.4) increased significantly compared to preoperative value, whereas RPA-LPA ratio was not significantly changed (1.095 ± 0.39 vs 1.01 ± 0.56, P = 0.63). Prerepair pulmonary vascular resistance in 17 patients, who underwent complete repair, was 2.9 ± 0.69 woods unit/m². Postrepair right ventricle-left ventricle pressure ratio was 0.5 ± 0.14. There was no early or late mortality and none of the patient required conduit revision or VSD fenestration. On follow-up of 25.75 ± 17.94 months, 16 patients were in NYHA I and 1 patient was in NYHA II. Appropriate-sized RV-PA shunt is an effective strategy for achieving balanced pulmonary artery growth in VSD/PA with hypoplastic pulmonary arteries presenting late without the risk of pulmonary over circulation or systemic malperfusion.

Early results of ring-reinforced conduit and curved porcine patch in Sano-Norwood procedure

BACKGROUND

Patch augmentation of the aortic arch as well as construction of an unobstructed pulmonary blood supply are two important surgical targets in patients with hypoplastic left heart syndrome. In this report, we aimed to present our preliminary results with a combination of two relatively new approaches in Norwood-Sano procedure.

METHODS

A retrospective analysis was performed in 10 newborns with the diagnosis of hypoplastic left heart syndrome. Our surgical approach incorporated the interposition of a 6.0-mm ring-reinforced tube graft with the "dunked technique" between the right ventricle and the pulmonary artery; and reconstruction of the aortic arch using a curved porcine pericardial patch which is specifically designed for the Norwood procedure.

RESULTS

Mean age and body weight at the time of the Sano-Norwood operation were 7.3 ± 2.4 days and 3164 ± 406 g, respectively. We encountered 1 (10%) early and 1 (10%) late mortality. All of the patients were discharged without any residual gradients at the aortic arch. Four out of eight patients underwent stage 2 bidirectional cavopulmonary anastomosis at a median age of 5 months (range, 4-6 months). Pericardial patch augmentation of the left pulmonary artery was deemed mandatory in one of our patients.

CONCLUSIONS

The dunked technique of interposing a ring-reinforced conduit between the right ventricle and pulmonary artery along with the utilization of a curved porcine pericardial patch specifically designed for aortic arch reconstruction are promising modifications of the Sano-Norwood procedure in newborns with hypoplastic left heart syndrome.

Early Outcomes of Hypoplastic Left Heart Syndrome Infants: Meta-Analysis of Studies Comparing the Hybrid and Norwood Procedures

The hybrid strategy is an alternative to the traditional Norwood procedure for initial palliation of infants with hypoplastic left heart syndrome (HLHS) who are deemed to be at high surgical risk. Numerous single-center studies have compared the two procedures, showing similar early outcomes, although the cohort sizes are likely insufficiently powered to detect significant differences. The current meta-analysis aims to explore the early morbidity and mortality associated with the hybrid compared to the Norwood procedure. MEDLINE, Cochrane Libraries, and Embase were systematically searched, and 14 studies were included for statistical synthesis, comprising 263 hybrid and 426 Norwood patients. Early mortality was significantly higher in the hybrid patients (relative risk [RR] = 1.54, P < .05, 95% confidence interval [CI]: 1.02-2.34), whereas interstage mortality was comparable between the two groups (RR = 0.88, P > .05, 95% CI: 0.46-1.70). Six-month (RR = 0.89, P < .05, 95% CI: 0.80-1.00) and one-year (RR = 0.88, P < .05, 95% CI: 0.78-1.00) transplant-free survival was also inferior among the hybrid patients. Furthermore, the hybrid patients required more reinterventions following initial surgical palliation (RR = 1.48, P < .05, 95% CI: 1.09-2.01), although the two groups had comparable length of hospital and intensive care unit stay postoperatively. In conclusion, our results suggest that the hybrid procedure is associated with worse early survival compared to the traditional Norwood when used for initial palliation of infants with HLHS. However, due to the hybrid being used preferentially for high-risk patients, definitive conclusions regarding the efficacy of the procedure cannot be drawn.

Unplanned cardiac reoperations and interventions during long-term follow-up after the Norwood procedure†

OBJECTIVES

Patients with hypoplastic left heart syndrome or related malformations are predominantly treated with a 3-stage palliation. Anatomic or physiologic problems can lead to unplanned additional surgical or catheter interventions during single ventricle palliation. Changes in operative technique may have an impact on the reoperation rate.

METHODS

Between 1997 and 2014, 317 Norwood procedures were performed at our centre. A retrospective single centre investigation was carried out concerning incidence, timing, indication and type of unplanned interstage cardiac reoperations and catheter interventions during follow-up of Norwood patients. Patients were followed from birth until the end of 2015. Cardiac procedures taking place at the time of the bidirectional Glenn or Fontan procedure or heart transplantation were not included.

RESULTS

Sixty-five of the Norwood patients (20.5%) had at least one additional surgical cardiac procedure. Nine patients (2.8%) needed open procedures prior to the Norwood operations, 11.0% had procedures in the interstage I, 3.5% in the interstage II and 9.1% of the Fontan patients had cardiac reoperations afterwards. Main indications for unplanned surgery were insufficient pulmonary perfusion and tricuspid regurgitation. Eighty-one patients (25.6%) had at least one interstage catheter intervention during follow-up mainly addressing stenosis of the pulmonary arteries, aortic arch stenosis or aortopulmonary collaterals.

CONCLUSIONS

The number of unplanned reoperations and interventions during staged palliation is remarkably high showing surgical peaks in the interstage I and after the Fontan procedure and an interventional peak in the interstage II. Thorough early information of the parents about possibly anticipated additional procedures is necessary.

Long term survival of hypoplastic left heart syndrome infants: Meta-analysis comparing outcomes from the modified Blalock-Taussig shunt and the right ventricle to pulmonary artery shunt

BACKGROUND

Stage 1 palliation of hypoplastic left heart syndrome (HLHS) involves the Norwood procedure combined with a modified Blalock-Taussig shunt (mBTS) or right ventricle to pulmonary artery shunt (RVPAS). Short-term survival has been described previously, whereas longer-term outcomes remain a subject of debate. This meta-analysis aimed to describe the short and long-term survival outcomes of these two shunts, and explore factors that might influence survival.

METHODS

Medline, Cochrane Libraries and EMBASE were systematically searched, and 32 studies were included for statistical synthesis, comprising 1348 mBTS and 1258 RVPAS patients.

RESULTS

While early in-hospital survival was superior in the RVPAS group (RR=1.5, p<0.05, 95% CI: 1.21-1.85), this difference was lost from 2years post-stage 1 palliation (RR=0.91, p>0.05, 95% CI: 0.79-1.04), and maintained unchanged up to 6years. This shift in survival was also reflected in inter-stage survival, with superior RVPAS outcomes between stage 1 and 2 (RR=1.62, p<0.05, 95% CI: 1.39-1.88), and equivalent outcomes between stage 2 and 3. Potential contributors to this included a significantly higher rate of pulmonary artery stenosis in the RVPAS group and an increased requirement for shunt re-intervention in this group prior to stage 2.

CONCLUSIONS

Despite early advantages, RVPAS and mBTS for palliation of hypoplastic left heart syndrome produced comparable long-term survival. The RVPAS patients experienced more pulmonary artery stenosis and requirement for shunt re-intervention. The impact of shunt type on quality and survival with a Fontan is yet to be assessed.

Interstage evaluation of homograft-valved right ventricle to pulmonary artery conduits for palliation of hypoplastic left heart syndrome

OBJECTIVE

Palliation of hypoplastic left heart syndrome with a standard nonvalved right ventricle to pulmonary artery conduit results in an inefficient circulation in part due to diastolic regurgitation. A composite right ventricle pulmonary artery conduit with a homograft valve has a hypothetical advantage of reducing regurgitation, but may differ in the propensity for stenosis because of valve remodeling.

METHODS

This retrospective cohort study included 130 patients with hypoplastic left heart syndrome who underwent a modified stage 1 procedure with a right ventricle to pulmonary artery conduit from 2002 to 2015. A composite valved conduit (cryopreserved homograft valve anastomosed to a polytetrafluoroethylene tube) was placed in 100 patients (47 aortic, 32 pulmonary, 13 femoral/saphenous vein, 8 unknown), and a nonvalved conduit was used in 30 patients. Echocardiographic functional parameters were evaluated before and after stage 1 palliation and before the bidirectional Glenn procedure, and interstage interventions were assessed.

RESULTS

On competing risk analysis, survival over time was better in the valved conduit group (P = .040), but this difference was no longer significant after adjustment for surgical era. There was no significant difference between groups in the cumulative incidence of bidirectional Glenn completion (P = .15). Patients with a valved conduit underwent more interventions for conduit obstruction in the interstage period, but this difference did not reach significance (P = .16). There were no differences between groups in echocardiographic parameters of right ventricle function at baseline or pre-Glenn.

CONCLUSIONS

In this cohort of patients with hypoplastic left heart syndrome, inclusion of a valved right ventricle to pulmonary artery conduit was not associated with any difference in survival on adjusted analysis and did not confer an identifiable benefit on right ventricle function.

Proximal Pulmonary Artery Evaluation in Infants With Shunt-Dependent Pulmonary Blood Flow: Computed Tomographic Angiography Versus Transthoracic Echocardiography

Background:

Infants with shunt-dependent pulmonary blood flow are at risk for developing proximal pulmonary artery (PA) stenosis, which may result in morbidity and mortality. Transthoracic echocardiography (TTE) is the primary means of surveillance for PA narrowing but has significant limitations and has not been compared to computed tomographic angiography (CTA)–derived measurements of the proximal PA anatomy in this population.

Methods:

A retrospective chart review identified infants with shunt-dependent pulmonary blood flow who had both TTE and CTA performed <14 days apart during a five-year period. Proximal right pulmonary artery (RPA) and left pulmonary artery (LPA) diameters were measured by TTE and CTA. Pulmonary artery z-score, linear and intraclass correlation (ICC) coefficients, and Bland-Altman plots were computed.

Results:

Seventeen pairs of studies were analyzed. The TTE and CTA proximal PA diameters had moderate linear correlation and agreement ( R = 0.67, P ≤ .0001, ICC = 0.65); the RPA showed stronger correlation and agreement ( R = 0.76, P = .0004, ICC = 0.72) than the LPA (R = 0.59, P = .01, ICC = 0.59). Computed tomographic angiography detected missed PA stenosis ( Z score < −2) in five (14.7%) cases, four of which were on the LPA.

Conclusion:

In this study of infants with shunt-dependent pulmonary blood flow, TTE and CTA proximal PA diameters had only moderate correlation and agreement overall, which was worse when comparing LPA measurements. This resulted in missed PA stenosis by TTE. Computed tomographic angiography may be warranted in patients with poorly visualized PAs by TTE or suspicion for deficient pulmonary blood flow.

Ring-reinforced Sano conduit at Norwood stage I reduces proximal conduit obstruction

BACKGROUND

Reinterventions for proximal conduit obstruction or on the pulmonary arteries are frequent after the Sano-modified stage I Norwood palliation of hypoplastic left heart syndrome. We report our initial experience with a modified Sano technique using a ring-reinforced graft inserted transmurally through the right ventricle with a limited ventriculotomy.

METHODS

All patients who underwent the Sano-modified stage I Norwood procedure using a modified "dunked" technique from September 2010 to September 2012 at our institution were reviewed. An historical control group consisted of patients undergoing the traditional Sano right ventricle-to-pulmonary artery conduit anastomosed to the epicardium. The primary outcome measures included death, reintervention on the Sano and pulmonary arteries, and ventricular function.

RESULTS

The study included 29 patients. No patients required intervention on the Sano conduit, pulmonary arteries, or aortic arch before discharge after the stage I procedure. During a median follow-up of 20 months (range, 26 days to 3.3 years), survival was estimated at 96.6% ± 3.4% at 1 month and 86.2% ± 6.4% at the latest follow-up. One patient underwent heart transplantation. No interstage intervention was required on the proximal or distal Sano conduit. Intervention was required on the midportion of the conduit in 1 patient and on the pulmonary arteries in 3 patients. At the time of the bidirectional Glenn anastomosis, freedom from conduit and pulmonary artery intervention was estimated at 92.3% ± 7.4% and 90.1% ± 8.7%, respectively, and global right ventricular dysfunction was mild or less in 84% (16 of 19) of patients.

CONCLUSIONS

The ring-reinforced right ventricle-to-pulmonary artery Sano conduit transmurally inserted into the right ventricle provides acceptable results, with a low incidence of interstage reinterventions in patients undergoing stage I palliation.

Establishment of right ventricle-pulmonary artery continuity as the first-stage palliation in older infants with pulmonary atresia with ventricular septal defect may be preferable to use of an arterial shunt

OBJECTIVES

Right ventricle-pulmonary artery (RV-PA) conduit and systemic-to-pulmonary artery (S-PA) shunt in younger infants for the first-stage palliation with pulmonary atresia with ventricular septal defect (PAVSD) obtained good results. However, the pulmonary arteries (PA) grow slow in older infants undergoing an S-PA shunt. We compared the clinical outcomes of the two procedures in older infants with PAVSD.

METHODS

A total of 48 patients with PAVSD underwent the first-stage palliative procedure between January 2010 and July 2012. Patients were divided into the RV-PA group and the S-PA group based on whether they had an RV-PA conduit (n = 24) or an S-PA shunt (n = 24). The early and late outcomes were compared between groups.

RESULTS

There was no significant difference in in-hospital mortality, mechanical ventilation time, paediatric intensive care unit stay and hospital stay between groups (all P > 0.05). The RV-PA conduits were associated with better PA growth compared with the S-PA shunts (P < 0.001). The RV-PA group had a higher rate of second-stage biventricular surgery compared with the S-PA group (P = 0.03). The early outcomes among different conduits of the RV-PA conduit were not different (all P > 0.05). A positive correlation was found between the size of conduits and body weight (R(2) = 0.684, P < 0.001).

CONCLUSIONS

In older infants with PAVSD who underwent the first-stage palliative procedure, early outcomes showed no difference between the RV-PA conduit group and the S-PA shunt group. The RV-PA conduits were associated with better growth of the PA and higher rates of second-stage biventricular repair. Autologous pericardium is a good choice for RV-PA conduits, and there is a correlation between body weight and size of conduit.

Pulmonary arterioplasty with decellularized allogeneic patches

BACKGROUND

Decellularized allogeneic nonvalved pulmonary artery patches for arterioplasty are a relatively new option compared with cryopreserved allogeneic, crosslinked xenogeneic bioprosthetic or synthetic materials. This study examines the midterm experience with a new decellularized allogeneic patch for congenital cardiac reconstructions.

METHODS

For this prospective postmarket approval, nonrandomized, inclusive observational study, we collected data on a consecutive cohort of 108 patients with cardiovascular reconstructions using 120 decellularized allogeneic pulmonary artery patches (MatrACELL; LifeNet Health, Inc, Virginia Beach, VA) between September 2009 and December 2012. One hundred of the patches were used for pulmonary arterioplasties. Two patients were lost early to follow-up and excluded from subsequent survival and durability analyses. Data included demographics, surgical outcomes, subsequent reoperations, and catheter reinterventions. These variables were also collected for an immediately preceding retrospective consecutive cohort of 100 patients with 101 pulmonary arterioplasty patches who received classical cryopreserved pulmonary artery allografts (n=59 patches and patients) or synthetic materials (n=41 patients with 42 patches) for pulmonary arterioplasties between 2006 and 2009.

RESULTS

In 106 patients with 118 decellularized patches, there were no device-related serious adverse events, no device failures, and no evidence of calcifications on chest roentgenograms. In contrast, the prior comparative pulmonary arterioplasty cohort of 100 patients experienced an overall 14.0% patch failure rate requiring device-related reoperations (p<0.0001) at mean duration of 194±104 days (range, 25 to 477 days).

CONCLUSIONS

The intermediate-term data obtained in this study suggest favorable performance by decellularized pulmonary artery patches, with no material failures or reoperations provoked by device failure.

Balloon angioplasty and stent implantation performed through systemic-to-pulmonary artery shunts in infants and neonates

Branch pulmonary artery stenosis (BPAS) in the setting of systemic-pulmonary artery shunts (SPS) may result in significant sequelae. Limited information exists regarding the safety and efficacy of pulmonary artery balloon angioplasty and stent implantation via SPS in neonates and infants. This study aimed to examine the feasibility, safety, and efficacy of balloon angioplasty/stent implantation for BPAS performed via SPS in neonates and infants. A single-center retrospective analysis of all patients weighing 10 kg or less who underwent angioplasty for BPAS via SPS was performed. Systemic oxygen saturations and vessel diameter before, during, and after the procedure were compared. Between July 1996 and February 2008, 15 patients underwent 20 catheterizations for the treatment of 27 BPAS via SPS. The patients had a mean weight of 5.6 kg (range, 2.6-10 kg) and a mean age of 7.6 months (range, 7 days to 33 months). The SPS diameter ranged between 2 and 5 mm (median, 3.5 mm). Angioplasty was performed for all 27 lesions, and an additional stent was placed in 5 of these. The average lesion diameter increased from 2.3 ± 1.5 to 4.7 ± 1.7 mm (p < 0.05), and 25 (93 %) of the 27 lesions met the predetermined criteria for success. Systemic oxygen saturation increased from 73 ± 9.5 % to 82 ± 6.8 % immediately after intervention and was 83 ± 7.9 % at discharge (p < 0.05). There were no instances of shunt thrombosis. Two patients experienced transient hypotension during the procedure. No procedural deaths occurred. The study findings suggest that balloon angioplasty or stent implantation performed via SPS appears to be safe and effective treatment for BPAS in neonates and infants.

Impact of shunt type on growth of pulmonary arteries after norwood stage I procedure: current best available evidence

The past decade has seen a substantial improvement in the outcome following surgical palliation for hypoplastic left heart syndrome. This has been attributed to modifications in the surgical as well as postoperative management strategies. One such modification is the reemergence of the right ventricle to pulmonary artery (RV-PA) shunt as an alternative to the modified Blalock-Taussig (mBT) shunt as the source of pulmonary blood flow. The RV-PA shunt has been shown to improve the immediate surgical outcome compared with the classic Norwood procedure with an mBT shunt. Despite the several reported advantages, the impact of the RV-PA shunt on growth of the pulmonary arteries and incidence of late development of central PA stenosis remains unclear. This systematic review evaluates the current best available evidence to address this issue and concludes that the evidence from retrospective studies and only available randomized controlled trial (RCT) is conflicting. The retrospective studies predominantly suggest that the Norwood procedure with RV-PA shunt may have favorable effects on the development of the pulmonary arteries due to even distribution of pulmonary blood flow with greater distal left pulmonary artery growth, resulting in more balanced distal branch pulmonary artery size albeit with a greater degree of central pulmonary artery hypoplasia needing surgical attention. On the contrary, the RCT reports that the overall size of the pulmonary artery on angiography before the stage II procedure was smaller in the RV-PA shunt group than in the mBT shunt group, with no information available on incidence of central pulmonary hypoplasia.

An angiographic predictor of pulmonary artery stenosis after the Norwood-Sano operation for hypoplastic left heart syndrome

The objective of this study was to determine angiographic predictors of future pulmonary artery stenosis (PS) in patients with hypoplastic left heart syndrome (HLHS) at the time of pre-stage 2 cardiac catheterization (PS2C). The Sano modification of the Norwood operation (NSO) for HLHS includes placement of a right ventricle-to-pulmonary artery (RV-PA) conduit. Branch PS is a recognized complication. Data from patients with HLHS who underwent NSO from 2005 to 2009 and who underwent PS2C were reviewed retrospectively. Nakata and McGoon indices were calculated in the traditional fashion, and modified Nakata and McGoon indices were calculated using the narrowest branch PA diameters. Thirty-three patients underwent NSO and 28 patients underwent PS2C. Mean follow-up was 35.8 ± 7.5 months. Ten (36 %) patients had significant left branch PS, with two requiring balloon angioplasty and eight requiring stent placement, a median of 15.2 months after PS2C (interquartile range 1.2, 32.8). The modified Nakata index was predictive of future intervention for left PS (receiver operating characteristic curve area under the curve 0.811), with a cut-off of 135 mm(2)/m(2) and a sensitivity of 100 % and specificity of 72.2 %. A modified Nakata index <135 mm(2)/m(2) at PS2C predicts future need for intervention on left-branch PS in patients with HLHS after the NSO. Surgical pulmonary arterioplasty at the time of stage 2 surgical palliation may obviate the need for future interventions.

Size of the right ventricle-to-pulmonary artery conduit impacts mid-term outcome after the Norwood procedure in patients weighing less than 3 kg

OBJECTIVE

The optimal shunt size for patients who have the Norwood operation with a right ventricle-to-pulmonary artery conduit is controversial. The goal of this study is to compare outcomes of 2 shunt sizes in this population.

METHODS

Between 2002 and 2010, 75 consecutive patients diagnosed with hypoplastic left heart syndrome and its variants underwent the Norwood procedure with a right ventricle-to-pulmonary artery conduit. The outcomes of 20 neonates weighing <3 kg were analyzed.

RESULTS

The cumulative 30-day stage 1 survival [corrected] was 97% (95% confidence interval, 88%-99%) for all patients (73/75), 20 of whom weighed <3 kg. Nine patients had a 6-mm (group 1) and 11 patients had a 5-mm (group 2) right ventricle-to-pulmonary artery conduit. Thirty-day stage 1 survival was 88% (8/9) in group 1 and 90% (10/11) in group 2 (P = .88). The central pulmonary artery confluence size at prebidirectional cavopulmonary shunt catheterization was 4.5 ± 1.2 mm in group 1 and 2.5 ± 1.0 mm in group 2 (P = .009). The mean transpulmonary gradient was higher in group 2 (7.8 ± 3.1 mm Hg vs 4.2 ± 1.9 mm Hg; P = .036). The incidence of pulmonary artery intervention was 16% (1/7) in group 1 and 75% (6/8) in group 2 (P = .030). Survival rate at 6 months was 66% (6/9) in group 1 and 70% (7/10) in group 2 (P = .89).

CONCLUSIONS

Use of a 6-mm right ventricle-to-pulmonary artery conduit showed better central pulmonary artery growth and less need for pulmonary artery intervention in the authors' experience.

Proximal sano anastomosis aneurysm due to degeneration of bovine pericardial patch

We report a 5-year-old girl with hypoplastic left heart syndrome who originally underwent a Norwood procedure with a Sano shunt. Subsequent procedures included a bidirectional Glenn and extracardiac Fontan with a Gore-Tex graft (W.L Gore and Associates, Flagstaff, AZ). The patient was found to have a heart murmur on a follow-up visit 3 years later. Echocardiography and computed tomography imaging showed an aneurysm of the proximal Sano anastomosis. The patient underwent successful surgical repair.

Usefulness of balloon angioplasty for the right ventricle-pulmonary artery shunt with the modified Norwood procedure

OBJECTIVE

We sought to evaluate the efficacy of balloon angioplasty (BA) for severely desaturated patients due to a stenotic right ventricle (RV) to pulmonary artery (PA) shunt following modified Norwood procedure.

METHODS

Of 87 patients who underwent a Norwood procedure with the RV-PA shunt between February 1998 through March 2010, 22 (25%) patients underwent BA. The efficacy of BA was assessed by angiographic measurement of the changes in the internal diameters of the stenotic portions of the shunt, changes in arterial saturation and clinical outcomes.

RESULTS

BA was performed for stenotic RV-PA shunts following stage I palliation (n = 17, 77%), or those placed as an additional blood source (n = 5, 23%, 3 patients awaiting biventricular repair, 2 patients following stage II palliation). The location of the BA was at the distal anastomosis in 12 (54.5%), proximal anastomosis in 21 (95.4%) and in the mid-portion of the shunt in 11 (50%) cases. The diameters of these three shunt portions were measured from the anterior-posterior and lateral angiographic images, increasing significantly after BA (p < 0.0001) in all. Arterial saturation significantly improved after BA in all cases (66.5 ± 4.3% to 79.4 ± 3.4%, p < 0.0001). Freedom from reintervention was 100%. All patients underwent subsequent elective planned surgery at an appropriate age with no mortality.

CONCLUSIONS

A BA-alone strategy for a stenotic RV-PA shunt was effective for all three shunt portions, minimizing shunt-related premature surgical intervention.

Effect of endovascular stenting of right ventricle to pulmonary artery conduit stenosis in infants with hypoplastic left heart syndrome on stage II outcomes

There is growing awareness that the Norwood procedure with the Sano modification is prone to early right ventricular to pulmonary artery (RV-PA) conduit stenosis resulting in systemic oxygen desaturation, increased interstage morbidity, and death. We report our experience with endovascular stent placement for conduit stenosis and compare the outcomes at stage II surgery between stented and nonstented infants. The medical records of all patients with hypoplastic left heart syndrome who received an RV-PA conduit at Norwood palliation from May 2005 to January 2010 were reviewed. The preoperative anatomy, demographics, operative variables, and outcomes pertaining to the Norwood and subsequent stage II surgeries were obtained and compared between stented and nonstented infants. The pre- and post-stent oxygen saturation, stenosis location, type and number of stents implanted, concomitant interventions, procedure-related complications, and reinterventions were collected. Of the 66 infants who underwent the Norwood procedure with RV-PA conduit modification, 16 (24%) received stents. The anatomy, demographics, and outcome variables after the Norwood procedure were similar between the stented and nonstented infants. The age at catheterization was 93 ± 48 days, and the weight was 4.9 ± 1.2 kg. The oxygen saturation increased from 66 ± 9% before intervention to 82 ± 6% immediately after stenting (p <0.0001). No interstage surgical shunt revisions were performed in either group. Age, weight, pre-stage II echocardiographic variables, oxygen saturation, and operative and outcome variables, including mortality, were similar between the 2 groups. In conclusion, endovascular stent placement for RV-PA conduit stenosis after the Norwood procedure leads to improved systemic oxygen levels and prevents early performance of stage II surgery without compromising stage II outcomes.

Second-Stage Palliation After Bilateral Pulmonary Artery Bands for HLHS and its Variants—Which is Better, Modified Norwood or Norwood Plus Bidirectional Glenn?

Background. The purpose of this study was to evaluate the surgical outcomes and pulmonary artery (PA) development associated with a new strategy wherein the modified Norwood (N) procedure is performed at 1-2 months after bilateral pulmonary artery banding (PAB). Methods. Between January 2008 and February 2010, 16 patients underwent Norwood-type operation after previous bilateral PAB. For analysis, patients were divided into two groups. Group I (n = 11) underwent modified Norwood procedure with either right modified Blalock Taussig (RMBT) shunt (n = 4) or right ventricle to pulmonary artery (RV-PA) conduit (n = 7). Group II (n = 5) underwent Norwood procedure plus bidirectional Glenn anastomosis. Diagnoses were hypoplastic left heart syndrome in 6 and its variants in 10. Results. There was no surgical death and no late death. Pulmonary artery interventions were performed at the time of the Norwood procedure in 27% in Group I and in 100% in Group II (p < 0.05). Additional PA interventions were performed during the period of follow-up in 4 cases in Group I (36.4%), and in 4 cases in Group II (80.0%). Additional Blalock Taussig shunts were performed in 7 patients, resulting in significant increase in PA index. In all, four patients have reached total cavopulmonary connection, and one has undergone biventricular repair. Eight patients in Group I and one patient in II Group reached bidirectional Glenn anastomosis. In Gp II, two patients showed LPA narrowing or obstruction with PA index of 80 ± 12 mm2/m2. Conclusions. Regarding the second-stage palliation after bilateral PAB, modified Norwood procedure with either RMBT or RV-PA conduit has some advantages compared with Norwood plus BDG with respect to subsequent pulmonary artery development. Additional BT shunt may contribute to PA development, even in the patients with Norwood procedure with RV-PA conduit.

Staged single-ventricle palliation in 2011: outcomes and expectations

Outcomes for staged palliation for single-ventricle heart disease have improved over the past two decades. As outcomes improve, parental expectations for survival and quality of life have risen accordingly. Nevertheless, the number of interventions and complications these patients must endure remain high. The final surgical destination of the single-ventricle patient, the total cavopulmonary connection (or Fontan operation) successfully separates systemic venous and pulmonary venous blood flow but does so at great cost. Fontan patients remain at significant risk of complications despite what are perceived to be "favorable" hemodynamics. The outcomes in this population are discussed in this review, with particular attention to the history behind our current strategies as well as to recent salient studies.