Risk-stratified approach to hybrid transcatheter-surgical palliation of hypoplastic left heart syndrome

Practice variation using the hybrid stage I procedure in congenital heart disease: Results from a national survey

Objectives

Hybrid stage I palliation has been used in many clinical scenarios including initial palliation in single ventricle heart disease, a bridge to biventricular repair, a bridge to transplant, and as a destination therapy. There is considerable hybrid stage I palliation practice variation, which we aimed to better understand in this study.

Methods

Survey-based assessment of practice variation related to hybrid stage I palliation was sent to congenital heart centers across the United States and Canada.

Results

Of the 106 centers surveyed, responses were received from 54 centers (50.9%). Of respondents, 45 centers perform hybrid stage I palliation. Centers most commonly (97.7%) perform hybrid stage I palliation on "high-risk" patients with single ventricle heart disease. Regarding the technical aspects of hybrid stage I palliation, most centers (95.3%) accomplish restrictive pulmonary blood flow using pulmonary artery bands and primarily use changes in oxygen saturation (34.1%) to identify appropriate restriction. Ductal stents are most often used (67.4%) to maintain ductal patency. Only 10 centers (23.3%) routinely enlarge the atrial septal defect. Indications for atrial septal defect intervention varied widely. Most centers (71.9%) discharge patients home to follow with a formal "interstage" program.

Conclusions

There is significant variation in practice patterns for hybrid stage I palliation indications, technical aspects, and postoperative care. Therefore, generalizability of single-center studies on outcomes after hybrid stage I palliation is limited. Future multicenter studies are needed to best delineate which patients benefit most from hybrid stage I palliation and to further define optimal approaches to caring for these patients.

Hybrid Interventions in Congenital Heart Disease: A Review of Current Practice and Rationale for Use

BACKGROUND

Hybrid interventions have become a common option in the management for a variety of patients with congenital heart disease. In this review, we discuss the data that have driven decision making about hybrid interventions to date.

METHODS

The existing literature on various hybrid approaches was reviewed and summarized. In addition, the key tenants to creating a successful hybrid program within a congenital heart center are elucidated.

RESULTS

Hybrid strategies for single-ventricle patients, pulmonary atresia with intact ventricular septum, branch pulmonary artery stenosis, and muscular ventricular septal defect closure have important benefits and limitations compared with traditional approaches.

CONCLUSION

A growing body of evidence supports the use of hybrid interventions in congenital heart disease. But important questions remain regarding improved survival and other long-term outcomes, such as neurocognition, that might impact widespread adoption as a primary treatment strategy.

Comparison of Morbidity and Mortality Outcomes between Hybrid Palliation and Norwood Palliation Procedures for Hypoplastic Left Heart Syndrome: Meta-Analysis and Systematic Review

Background/Objectives: Hybrid palliation (HP) procedures for hypoplastic left heart syndrome (HLHS) are increasing. Our objective was to compare mortality and morbidity following HP and NP (Norwood palliation) procedures. Methods: Systematic review and meta-analysis of HLHS patients of peer-reviewed literature between 2000 and 2023. Mortality and/or heart transplantation in HP versus NP in the neonatal period, interstage period, and at 1, 3 and 5 years of age, and morbidity including completion of Stage II and Stage III palliation, unexpected interventions, pulmonary artery pressures, right ventricle function, neurodevelopmental outcomes and length of hospital stay were evaluated. Results: Twenty-one (meta-analysis: 16; qualitative synthesis: 5) studies evaluating 1182 HLHS patients included. HP patients had higher interstage mortality (RR = 1.61; 95% CI: 1.10-2.33; p = 0.01) and 1-year mortality (RR = 1.22; 95% CI: 1.03-1.43; p = 0.02) compared to NP patients without differences in 3- and 5-years mortality. HP procedure in high-risk HLHS patients had lower mortality (RR = 0.48; 95% CI: 0.27-0.87; p = 0.01) only in the neonatal period. HP patients underwent fewer Stage II (RR = 0.90; 95% CI: 0.81-1.00; p = 0.05) and Stage III palliation (RR = 0.78; 95% CI: 0.69-0.90; p < 0.01), had more unplanned interventions (RR = 3.38; 95% CI: 2.04-5.59; p < 0.01), and longer hospital stay after Stage I palliation (weighted mean difference = 12.88; 95% CI: 1.15-24.62; p = 0.03) compared to NP patients. Conclusions: Our study reveals that HP, compared to NP for HLHS, is associated with increased morbidity risk without an improved survival rate.

Mortality and Heart Transplantation After Hybrid Palliation of Hypoplastic Left Heart Syndrome: A Systematic Review and Meta-Analysis

BACKGROUND

Newborns with hypoplastic left heart syndrome (HLHS) who are considered at increased risk for death following Norwood/Sano surgery often undergo hybrid palliation (HP) as initial surgery. We aimed to compile the HP experience in HLHS and its variants and assess the rates of, and risk factors for, death and heart transplantation.

METHODS

CINAHL, CINAHL PLUS, PubMed/MEDLINE, and SCOPUS were systematically searched for HP outcome studies of death or heart transplantation in HLHS between 1998 and 2022. Pooled incidence was estimated, and potential risk factors were identified using random-effects meta-analysis and reconstructed time-to-event data from Kaplan-Meier curves.

RESULTS

Thirty-three publications were included in our review. Overall, of 1,162 patients 417 died and 57 underwent heart transplantation, resulting in a combined outcome of 40.7%, (474/1,162). There was a trend toward decreasing mortality risk across the stages of palliation. Pooled mortality between HP and comprehensive stage 2 palliation was 25%, after stage 2 up to Fontan palliation was 16%, and 6% post-Fontan. The incidence of death or heart transplantation was higher in high-risk patients-43% died and 10% received heart transplantation.

CONCLUSION

Our systematic review and meta-analysis found high rates of death or heart transplantation in HP of HLHS patients between HP and Fontan surgeries. All patients should be closely followed during the initial interstage period, which is associated with the highest hazard. Prospective studies on appropriate patient selection, indications, and / or alternatives, as well as refining HP strategies for managing newborns with HLHS are needed to improve outcomes.

Tricuspid Valve Regurgitation in Hypoplastic Left Heart Syndrome: Current Insights and Future Perspectives

Hypoplastic Left Heart Syndrome (HLHS) is a congenital heart defect that requires a three-stage surgical palliation to create a single ventricle system in the right side of the heart. Of patients undergoing this cardiac palliation series, 25% will develop tricuspid regurgitation (TR), which is associated with an increased mortality risk. Valvular regurgitation in this population has been extensively studied to understand indicators and mechanisms of comorbidity. In this article, we review the current state of research on TR in HLHS, including identified valvular anomalies and geometric properties as the main reasons for the poor prognosis. After this review, we present some suggestions for future TR-related studies to answer the central question: What are the predictors of TR onset during the three palliation stages? These studies involve (i) the use of engineering-based metrics to evaluate valve leaflet strains and predict tissue material properties, (ii) perform multivariate analyses to identify TR predictors, and (iii) develop predictive models, particularly using longitudinally tracked patient cohorts to foretell patient-specific trajectories. Regarded together, these ongoing and future efforts will result in the development of innovative tools that can aid in surgical timing decisions, in prophylactic surgical valve repair, and in the refinement of current intervention techniques.

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.

The Evolution of Therapeutic Strategies: Niche Apportionment for Hybrid Palliation

Hybrid palliation, the concept to stabilize univentricular circulation with bilateral pulmonary artery banding and maintenance of ductal patency, has significantly widened the therapeutic spectrum for patients with single-ventricle malformations or borderline hypoplasia. The concept has already been a part of early attempts to improve outcome in hypoplastic left heart syndrome but has not attracted much attention initially. Technical refinement and expertise have led to results that ultimately allowed the palliative strategy to gain traction and to be selectively adopted. By now, we have gained almost 2 decades of experience, and as much as hybrid palliation has changed our approach to single-ventricle management, new strategies and indications have been formed by this experience. We therefore review concepts and patterns of use of hybrid palliation as well as benefits and challenges of the respective pathways to highlight the current status of the hybrid procedure.

Innovative interventional catheterization techniques for congenital heart disease

Since 1929, when the first cardiac catheterization was safely performed in a human by Dr. Werner Forssmann (on himself), there has been a rapid progression of cardiac catheterization techniques and technologies. Today, these advances allow us to treat a wide variety of patients with congenital heart disease using minimally invasive techniques; from fetus to infants to adults, and from simple to complex congenital cardiac lesions. In this article, we will explore some of the exciting advances in cardiac catheterization for the treatment of congenital heart disease, including transcatheter valve implantation, hybrid procedures, biodegradable technologies, and magnetic resonance imaging (MRI)-guided catheterization. Additionally, we will discuss innovations in imaging in the catheterization laboratory, including 3D rotational angiography (3DRA), fusion imaging, and 3D printing, which help to make innovative interventional approaches possible.

Decision-Making for Surgery in the Management of Patients with Univentricular Heart

A series of technical refinements over the past 30 years, in combination with advances in perioperative management, have resulted in dramatic improvements in the survival of patients with univentricular heart. While the goal of single-ventricle palliation remains unchanged - normalization of the pressure and volume loads on the systemic ventricle, the strategies to achieve that goal have become more diverse. Optimal palliation relies on a thorough understanding of the changing physiology over the first years of life and the risks and consequences of each palliative strategy. This review describes how to optimize surgical decision-making in univentricular patients based on a current understanding of anatomy, physiology, and surgical palliation.

Stenting the neonatal arterial duct

Ductal stenting in neonates with either duct-dependent pulmonary or systemic circulation has become a good alternative for the initial palliation of complex congenital heart disease. Changes of stent and catheter technology (low profile, flexible, premounted stents with good scaffolding), better patient selection and preparation, optimal interventional access and covering the complete length of the duct have significantly improved results.

Is routine rapid-staged bilateral pulmonary artery banding before stage 1 Norwood a viable strategy?

OBJECTIVE

We adopted a policy of rapid-staged bilateral pulmonary artery banding (bPAB) before the Norwood (NW) procedure for all patients with hypoplastic left heart syndrome. We hypothesized that this strategy might mitigate some of the traditional risk factors and that postponing a major bypass procedure beyond the newborn period could have both short- and long-term benefits. The purpose of the present study was to evaluate the efficacy of this strategy with respect to the short-term outcomes.

METHODS

From 2008 to 2010, 14 patients underwent bPAB and maintenance of ductal patency with prostaglandin E1 infusion before stage 1 NW. For reference, we also reviewed the data from patients who had undergone the primary NW procedure in the 2 years immediately before the study period.

RESULTS

The bPAB was performed at a median age of 6 days (range, 2-39), gestational age of 38.5 weeks (range, 36-41), and weight of 2.75 kg (range, 2.3-3.6). The subsequent NW was performed at a gestational age of 43.5 weeks (range, 41-51) and weight of 3.2 kg (range, 2.2-4.9). When the NW procedure was eventually performed on the pBAB group, the maximum blood lactate levels within the first 24 hours after the NW were lower than those in the earlier primary NW group (2.8±0.9 vs 10.1±6.5 mmol/dL, P=.0002) and the urine output in the first 24 hours after the NW was greater in the pPAB group (4.1±2.1 vs 2.2±1.5 mL/kg/h; P=.0051).

CONCLUSIONS

These data suggest that rapid-staged bPAB before NW can reduce the challenge of postoperative management in the early postoperative period after the NW procedure and have potential to improve the outcomes.

Current status of the hybrid approach for the treatment of hypoplastic left heart syndrome

The hybrid approach for hypoplastic left heart syndrome (HLHS), consisting of bilateral pulmonary artery banding and ductal stenting, has emerged as an alternative to the traditional Norwood approach. This approach defers open heart surgery to beyond the neonatal period, which is believed to reduce postoperative mortality and morbidity and improve neurological development as compared with the conventional approach. However, there have been no scientific studies supporting these hypotheses. Recently, there seems to be a tendency that many centers recommend the hybrid approach as an interim procedure to rescue preoperative high-risk patients. Currently, the decision to adopt the hybrid approach or the Norwood approach seemed to be based on the preference of congenital heart surgeons and cardiologists. Further investigation including a randomized multi-center study would allow a scientific decision as to which approach is more appropriate for the patient with HLHS.

Bilateral pulmonary artery banding as rescue intervention in high-risk neonates

BACKGROUND

Presentation in shock and preoperative infection remain risk factors for neonatal cardiac surgery. This report describes bilateral pulmonary artery banding (bPAB) in ductal-dependent lesions with systemic outflow obstruction as rescue intervention before surgery with cardiopulmonary bypass in these high-risk neonates.

METHODS

A retrospective chart review was conducted for 10 patients who underwent bPAB before conventional surgery with cardiopulmonary bypass. Patient characteristics including birth weight, gestational age, cardiac and noncardiac diagnoses, preoperative and postoperative markers of organ function, and outcome measures were examined.

RESULTS

The majority of patients (8 of 10) were considered high-risk owing to multiorgan dysfunction syndrome. The median age at bPAB was 12 days (range, 5 to 26 days), and the median interval between bPAB and second surgery was 10.5 days (range, 5 to 79 days). Organ function improved after admission and continued to improve after bPAB in 9 of 10 patients. No patient experienced new complications between bPAB and subsequent operation. Of 8 patients who had stage I palliation, 5 have undergone or are awaiting completion Fontan, 1 underwent Kawashima procedure, 1 underwent orthotopic heart transplant, and 1 with hypoplastic left heart syndrome and intact atrial septum died at 44 days old. Both patients who underwent biventricular repair are alive and well. Median follow-up for survivors was 2.9 years (range, 0.25 to 6.25 years).

CONCLUSIONS

Bilateral pulmonary artery banding is safe in ductal-dependent lesions with systemic outflow obstruction. High-risk patients with preoperative organ dysfunction or infection can recover within a short period and become lower risk candidates for complex congenital heart surgery using cardiopulmonary bypass.

Bilateral pulmonary artery banding for resuscitation in high-risk, single-ventricle neonates and infants: a single-center experience

OBJECTIVES

Bilateral pulmonary artery banding with or without ductal stenting has been performed as a resuscitative intervention for patients considered at too high risk for conventional single ventricle palliation. The purpose of the present study was to determine the outcomes using this strategy.

METHODS

We performed a retrospective review of 24 patients with single ventricle anatomy who were younger than 3 months who had undergone bilateral pulmonary artery banding and ductal stenting or maintenance of prostaglandin E(1) from January 2007 to October 2011 at our institution. The echocardiographic, angiographic, operative, and clinical data were reviewed. Follow-up data were available for 100% of the patients.

RESULTS

All 24 patients (13 male patients) underwent bilateral pulmonary artery banding at a median age of 8 days (range, 2-44 days). Their gestational age was 38 weeks (range, 27-41 weeks), and their weight was 3.01 kg (range, 1.5-4.4 kg). The cardiac diagnoses included hypoplastic left heart syndrome/variant hypoplastic left heart syndrome in 18, unbalanced atrioventricular canal in 4, and tricuspid atresia in 2. In the hypoplastic left heart syndrome group, 9 (50%) had an intact or a highly restrictive atrial septum requiring open (n = 1) or transcatheter (n = 8) atrial septostomy with or without atrial stent placement (n = 4). Ductal stenting was performed in 14 patients, and 10 patients were continued with prostaglandin E(1). Fifteen patients (62.5%) survived to undergo a Norwood procedure (n = 7), comprehensive stage 2 (n = 1), or primary cardiac transplantation (n = 7). Of the 9 who died, support was withdrawn in 5 because of a contraindication to transplantation, 1 because of sepsis and/or multiorgan system failure, and 1 for whom palliative care was desired. Two died awaiting transplantation. All 7 patients who underwent a conventional Norwood operation survived to discharge, and 6 of the 7 (85.7%) underwent bidirectional Glenn shunt placement. Of the 7 patients who underwent transplantation, 6 (85.7%) were alive at a median follow-up of 33.6 months.

CONCLUSIONS

Bilateral pulmonary artery banding with or without ductal stenting is an effective method of resuscitation for high-risk neonates and infants with a single ventricle, allowing for reasonable survival to conventional first-stage palliation or primary transplantation.

Use of a pressure guidewire to assess pulmonary artery band adequacy in the hybrid stage I procedure for high-risk neonates with hypoplastic left heart syndrome and variants

OBJECTIVE

The hybrid stage I procedure is an alternative palliative strategy for patients with hypoplastic left heart syndrome who traditionally have undergone the Norwood operation. At our institution, the hybrid stage I procedure is employed only for patients with high operative risk. Our objective was to describe our use of a pressure guidewire during the hybrid stage I procedure to assess quantitatively pulmonary artery band adequacy.

DESIGN

After reviewing the charts on all high-risk patients who underwent a hybrid stage I procedure at our institution, we compared two groups of patients: those who underwent the standard hybrid stage I palliation (standard cohort) and those with pressure wire-facilitated assessment of distal branch pulmonary artery pressure (pressure wire cohort) to evaluate the impact of pressure guidewire use on procedural risk, radiation time, patient outcomes, and need for reoperation for pulmonary artery band adjustment.

RESULTS

The pressure guidewire was used in 8 of 14 patients at the time of hybrid stage I procedure and was successful and without complication in all attempts. In the standard cohort, 67% of patients needed reoperation for pulmonary artery band adjustment, compared to 12.5% of patients in the pressure wire cohort (P =.09). Procedure time, radiation exposure, and survival to hospital discharge were not different between groups.

CONCLUSIONS

This novel use of a pressure guidewire to assess quantitatively pulmonary artery band adequacy at the time of placement is feasible, safe and may decrease the need for reoperation for pulmonary artery band adjustment.

Preoperative pulmonary hemodynamics and assessment of operability: is there a pulmonary vascular resistance that precludes cardiac operation?

Preoperative pulmonary vascular disease remains an important risk factor for death or right-heart failure in selected children undergoing two-ventricle repair, single-ventricle palliation, or heart transplantation. Preoperative criteria for poor outcome after operation remain unclear. The purpose of this review is to critically assess both the historic and current data and make recommendations where appropriate. An extensive literature search was undertaken in October 2009. Data were analyzed by an expert multidisciplinary team and recommendations were made by consensus. PubMed was searched in October 2009. Data were analyzed and recommendations were made by consensus of a multidisciplinary team. In patients with suspected pulmonary vascular disease anticipating a two-ventricle repair, although preoperative testing via cardiac catheterization with vasodilators is reasonable, the preoperative parameters and the precise values of these parameters that best correlate with early and late outcome remain unclear. Further investigation is warranted in selected populations, such as the growing group of children with congenital heart disease complicated by chronic lung disease of prematurity, and in the developing world where patients may be more likely to present late with advanced pulmonary vascular disease. In patients with a functional single ventricle, there is growing evidence that mean pulmonary artery pressure of >15 mm Hg may be associated with both early and late mortality after the Fontan operation. The relationship of preoperative pulmonary hemodynamics to early and late morbidity remains to be defined. There most likely is a level of preoperative pulmonary vascular disease that puts an individual patient at increased risk for death or severe cyanosis after a bidirectional cavopulmonary anastomosis. It remains unclear, however, how to best assess this risk preoperatively. The limitations in obtaining an accurate assessment of pulmonary vascular disease in the complex single ventricle are discussed. In children awaiting cardiac transplantation with elevated pulmonary vascular disease of >6 U.m and/or transpulmonary gradient of >15 mm Hg, heart transplantation is deemed feasible in most transplant centers if the administration of inotropes or vasodilators can decrease the pulmonary vascular disease to <6 U.m or transpulmonary gradient to <15 mm Hg. In patients with preoperative pulmonary vascular disease, there may be contributing factors to the pulmonary vascular disease, such as the specifics of the cardiac lesion (atrioventricular valve regurgitation, low cardiac output), parenchymal and/or airway issues, and/or individual genetic predisposition. Amelioration of any reversible factors before operation and optimization of their management in the preoperative and postoperative period are recommended.

The retrograde aortic arch in the hybrid approach to hypoplastic left heart syndrome

BACKGROUND

Before palliative stage 2 for hypoplastic left heart syndrome, the coronary and cerebral circulations are often dependent on retrograde perfusion by means of the aortic arch. Results of hybrid palliation with a focus on patients exhibiting retrograde aortic arch obstruction (RAAO) were analyzed.

METHODS

From July 2002 to March 2008 66 consecutive hybrid procedures for hypoplastic left heart syndrome were performed. Patients requiring RAAO intervention based on cardiology-surgery consensus were defined as group 1 (n = 16), whereas all other hypoplastic left heart syndrome patients formed group 2 (n = 50).

RESULTS

At birth there were no differences between groups in terms of demographics or cardiac function. Group 1 had more patients with aortic atresia (94% versus 58%; p = 0.01), and 69% of patients had initial echocardiographic comments regarding incipient RAAO versus 26% in group 2 (p = 0.007). The type of ductal stent, balloon versus self-expandable, did not influence the subsequent development of RAAO. Before RAAO intervention (mean age, 74 days), group 1 patients had significantly more tricuspid regurgitation. The main treatment for RAAO in group 1 was coronary stent insertion, with 3 patients having a reverse central shunt. At a mean follow-up of 611 days, group 1 had reduced survival interstage (56.3% versus 88%; p = 0.005) and overall (43.7% versus 70%; p = 0.03).

CONCLUSIONS

Clinically important RAAO occurred in 24% of the hypoplastic left heart syndrome patients in this series. If RAAO is detected at birth or early interstage, a Norwood operation is now favored. Palliative interventional catheterization remains very important mid and late interstage for continuing the hybrid strategy toward comprehensive stage 2.

The bilateral pulmonary artery banding for hypoplastic left heart syndrome with a diminutive ascending aorta

A one-day-old neonate who was diagnosed with hypoplastic left heart syndrome (HLHS), aortic atresia, with a diminutive ascending aorta, and mitral atresia, was referred to us for cardiogenic shock because of excessive pulmonary blood flow. The patient underwent bilateral pulmonary artery banding (bPAB). After bPAB, the patient's hemodynamics were still unstable because of coronary malperfusion, to proceed to undergo Norwood procedure at the age of 3 days. In this case, the stenosis of the ascending aorta, just proximal to the innominate artery caused coronary ischemia. The precise evaluation of the ascending aorta is necessary to perform the bPAB for HLHS with diminutive ascending aorta. If there is a sign of stenosis of the ascending aorta, the Norwood procedure should be performed as the first stage palliation, even for high-risk HLHS patients.

Cardiovascular magnetic resonance of pulmonary artery growth and ventricular function after Norwood procedure with Sano modification

For hypoplastic left heart syndrome (HLHS), there have been concerns regarding pulmonary artery growth and ventricular dysfunction after first stage surgery consisting of the Norwood procedure modified with a right ventricle-to-pulmonary artery conduit. We report our experience using cardiovascular magnetic resonance (CMR) to determine and follow pulmonary arterial growth and ventricular function in this cohort. Following first stage palliation, serial CMR was performed at 1 and 10 weeks post-operatively, followed by cardiac catheterization at 4-6 months. Thirty-four of 47 consecutive patients with HLHS (or its variations) underwent first stage palliation. Serial CMR was performed in 20 patients. Between studies, ejection fraction decreased (58 +/- 9% vs. 50 +/- 5%, p < 0.05). Pulmonary artery growth occurred on the left (6 +/- 1 mm vs. 4 +/- 1 mm at baseline, p < 0.05) but not significantly in the right. This trend continued to cardiac catheterization 4-6 months post surgery, with the left pulmonary artery of greater size than the right (8.8 +/- 2.2 mm vs. 6.7 +/- 1.9 mm, p < 0.05). By CMR, 5 had pulmonary artery stenoses initially, and at 2 months, 9 had stenoses. Three of the 9 underwent percutaneous intervention prior to the second stage procedure. In this cohort, reasonable growth of pulmonary arteries occurred following first stage palliation with this modification, although that growth was preferential to the left. Serial studies demonstrate worsening of ventricular function for the cohort. CMR was instrumental for detecting pulmonary artery stenosis and right ventricular dysfunction.

Hybrid approach for hypoplastic left heart syndrome: intermediate results after the learning curve

BACKGROUND

Lessons learned during the development of a novel hybrid approach have resulted in a reliable, reproducible alternative treatment for hypoplastic left heart syndrome (HLHS). Herein we report our results using this hybrid approach in a uniform risk cohort.

METHODS

This is a review of prospectively collected data on patients treated for HLHS using a hybrid approach (n = 40) between July 2002 and June 2007. The hybrid approach includes pulmonary artery bands, a ductal stent, and atrial septostomy as a neonate, comprehensive stage 2 procedure resulting in Glenn shunt physiology at six months and Fontan completion at two years.

RESULTS

Forty patients had a hybrid stage 1 with 36 undergoing a comprehensive stage 2 procedure. Fifteen patients have completed the Fontan procedure with 17 pending. Overall survival was 82.5% (33 of 40). The seven deaths included one at stage 1, two between stages 1 and 2, three at stage 2, and one between stages 2 and 3. One patient had successful heart transplantation during the interstage period.

CONCLUSIONS

The hybrid approach can yield acceptable intermediate results that are comparable with a traditional Norwood strategy. Potential advantages of the hybrid approach include the avoidance of circulatory arrest and shifting the major surgical stage to later in life. These data provide the platform for a prospective trial comparing these two surgical options to assess whether there is less cumulative impact with the hybrid approach, thereby improving end organ function, quality, and quantity of life.

A review of ductal stenting in hypoplastic left heart syndrome: bridge to transplantation and hybrid stage I palliation

There is increasing interest in applying ductal stenting technology to high-risk patients with hypoplastic left heart syndrome (HLHS). In this review, we present the complete history and a comprehensive up-to-date analysis of all available data on the use of ductal stenting as part of various hybrid strategies for the combined medical and surgical management of HLHS.

Implantation of stents to ensure an adequate interatrial communication in patients with hypoplastic left heart syndrome

AIMS

To assess the feasibility of interatrial stenting for left atrial decompression in infants with hypoplastic left heart syndrome treated by a "hybrid-approach", with bilateral surgical banding of the pulmonary arteries and percutaneous stenting of the arterial duct.

PATIENTS AND METHODS

We stented the atrial septum in 5 infants aged from 21 to 77 days, making the intervention as an elective procedure in 4, but as a rescue procedure in the fifth patient, who had a restrictive foramen. The stents, comprising 2 Jo-stents of 17 millimetres hand-crimped on a balloon catheter with dimensions of 10 by 20 millimetres, and 3 premounted Genesis stents with dimensions of 10 by 19 millimetres, were placed using a 6 French long or short sheath by femoral venous access. The stents were expanded under fluoroscopic guidance to create a slightly diabolo-shaped form that fitted the septum.

RESULTS

The percutaneous interventions were successfully performed in all cases, producing significant improvement in clinical condition after placement. The saturations of oxygen increased from an average of 64% plus or minus 18% to 88% plus or minus 7%, (p < 0.05). During a mean follow up of 2.5 months, without any anticoagulant therapy, there were no complications related to the stenting. Surgical removal of the stents was uneventful during reconstruction of the aortic arch and creation of a bidirectional cavopulmonary connection in 4 patients, and during cardiac transplantation in one.

CONCLUSION

In the context of the hybrid approach, definitive decompression of the left atrium can be achieved by stenting the atrial septum in infants with hypoplastic left heart syndrome. Placement of the stents is safe and effective, with insertion in the form of a diabolo reducing the risk of dislocation, as well as embolisation of the stent.

A new approach to hypoplastic left heart syndrome with an intact atrial septum

An intact atrial septum places infants with hypoplasia of the left heart into a group with an extremely high rate of mortality. We report a neonate, diagnosed antenatally, who was delivered by Caesarian section in the cardiac theatre, urgently placed onto cardiopulmonary bypass, and who then underwent an atrial septectomy and banding of both pulmonary arteries. After stabilisation, his arterial duct was stented, completing the first stage of hybrid palliation.

Reverse Blalock-Taussig Shunt Facilitates the Growth of the Ascending Aorta After Hybrid Palliation

A 13-day-old baby girl with tricuspid atresia (IIc), who was prematurely born at 32 weeks and 5 days of gestation and weighed 2.2 kg, underwent bilateral pulmonary artery banding, ductal stenting, and reverse Blalock-Taussig shunt. Cardiac computerized tomography at 4 months postoperatively showed that the ascending aorta outgrew the somatic growth, presumably thanks to the forward flow through the reverse Blalock-Taussig shunt. At 6 months postoperatively, the patient underwent a successful second-stage operation.

Hybrid palliation in hypoplastic left heart syndrome

PURPOSE OF REVIEW

Despite progressive improvement in surgical results, hypoplastic left heart syndrome remains one of the congenital heart abnormalities with the greatest morbidity and mortality. Hybrid approaches to management, combining surgical and interventional catheterization procedures, have been introduced to minimize exposure to cardiopulmonary bypass, and improve outcomes for these high-risk infants.

RECENT FINDINGS

First-stage palliation of hypoplastic left heart syndrome has been performed as a hybrid procedure combining surgical pulmonary artery banding with catheterization stenting of the ductus arteriosus and balloon atrial septostomy, especially in high-risk patients. Additionally, several centers have performed second-stage palliation - bidirectional Glenn or hemi-Fontan procedures - in a manner that allows the subsequent 'Fontan' procedure to be completed in the catheterization laboratory with a covered stent.

SUMMARY

These innovative procedures offer the potential of an alternative management strategy for hypoplastic left heart syndrome. They have been applied to a very limited number of patients and long-term results are not available. Their role in management of hypoplastic left heart syndrome remains to be defined, especially as results of conventional surgical management continue to improve.

Hybrid transcatheter-surgical palliation: basis for univentricular or biventricular repair: the Giessen experience

The outcome of patients with hypoplastic left heart (HLH) is determined by many factors, particularly by the first-step palliative procedure in newborns undergoing the Norwood procedure, its Sano modification, or, rarely, through challenging biventricular repairs. Duct stenting combined with bilateral pulmonary artery banding (PAB) is a new method employed as an alternative first-step approach in a number of centers worldwide. We describe this interventional-surgical "hybrid approach" as an additional strategy for the treatment of newborns with HLH syndrome and HLH complex. Between 1998 and April, 2006, 58 newborns underwent ductal stenting and bilateral PAB. These patients underwent surgical bilateral PAB initially, followed by percutaneous duct stenting; the only exception to this were patients in whom duct stenting was performed as a rescue procedure. Various balloon-expandable and self-expandable stents with different widths and lengths were used during the 8-year period of this study. Balloon dilatation of the atrial septum was performed when indicated. This included 5 patients in whom the atrial septum was stented. Aortic arch reconstruction (AAR) combined with a bidirectional cavopulmonary connection (BCPC) was performed at a median age of 4.8 months (range, 2.6-7.5), and total cavopulmonary connection (TCPC) was performed at a median age of 3.1 years (range, 2.5-4). Nine patients were listed for heart transplantation (HTX) and transplanted with AAR when a donor heart was available. Depending on growth of left ventricular structures, biventricular repair (BVR) was performed at a median age of 7.1 months (range, 3.5-10). Overall, 8 of 58 patients (13.8%) treated by the transcatheter-surgical hybrid approach died during the study period. The mortality rate for duct stenting was 1.7% (l/58), and it was 1.7% for bilateral PAB as well. Twenty-seven patients received an AAR/BCPC; 2 of them died (7.4%). Additionally, 1 of 2 patients with AAR/BCPC died while on the waiting list for HTX, resulting in a total mortality rate of 11% with an actuarial survival rate of 89%. One patient is still awaiting AAR + BCPC. Three patients died while on the waiting list for HTX despite successful bilateral PAB and duct stenting. The 30-day mortality rate for TCPC (n = 11), HTX (n = 8), and 18 patients with BVR was 0. The actuarial survival rate for patients with BVR is 93%. Postnatal transcatheter-surgical hybrid palliation expands the surgical options for newborns with HLH. Using hybrid palliation, Norwood stage I operation can be avoided in the neonatal period, the waiting period for children scheduled for cardiac transplantation can be extended, and observation for left ventricular growth suitable for biventricular repair as well.

Single-ventricle palliation for high-risk neonates: the emergence of an alternative hybrid stage I strategy

BACKGROUND

Survival after stage I palliation for hypoplastic left heart syndrome or related anomalies remains poor in high-risk neonates. We hypothesized that a less invasive hybrid approach would be beneficial in this patient population.

METHODS

The hybrid stage I procedure was performed in the catheterization laboratory. Via a median sternotomy, both branch pulmonary arteries were banded, and a ductal stent was delivered via a main pulmonary artery puncture and positioned under fluoroscopic guidance.

RESULTS

Between October 2003 and June 2005, 14 high-risk neonates underwent a hybrid stage I procedure. Eleven of 14 had hypoplastic left heart syndrome. Two also underwent peratrial atrial septal stenting, and 5 required percutaneous atrial stenting later. Two neonates with an intact or highly restrictive atrial septum had emergency percutaneous atrial stent placement. Hospital survival was 11 (78.5%) of 14. One patient required extracorporeal membrane oxygenation support for intraoperative cardiac arrest. He underwent cardiac transplantation but died later of sepsis. One patient died of ductal stent embolization, and a third died of progressive cardiac dysfunction. The first 4 patients required pulmonary artery band revisions. There were none after we modified our technique and added branch pulmonary artery angiograms. There were 2 interstage deaths from atrial stent occlusion and from preductal retrograde coarctation. Eight patients underwent stage II procedures, consisting of aortic arch reconstruction, atrial septectomy, and cavopulmonary shunt. Two patients died after stage II. One patient is awaiting stage II.

CONCLUSIONS

The hybrid stage I palliation is a valid option in high-risk neonates. As experience is accrued, it may become the preferred alternative. However, in aortic atresia, the development of preductal retrograde coarctation is a significant problem.