First-stage palliation for hypoplastic left heart syndrome in the twenty-first century

Association Between Remote Monitoring and Interstage Morbidity and Death in Patients With Single-Ventricle Heart Disease Across Socioeconomic Groups

BACKGROUND

Despite improvements in survival over time, the mortality rate for infants with single-ventricle heart disease remains high. Infants of low socioeconomic status (SES) are particularly vulnerable. We sought to determine whether use of a novel remote monitoring program, the Cardiac High Acuity Monitoring Program, mitigates differences in outcomes by SES.

METHODS AND RESULTS

Within the Cardiac High Acuity Monitoring Program, we identified 610 infants across 11 centers from 2014 to 2021. All enrolled families had access to a mobile application allowing for near-instantaneous transfer of patient information to the care team. Patients were divided into SES tertiles on the basis of 6 variables relating to SES. Hierarchical logistic regression, adjusted for potential confounding characteristics, was used to determine the association between SES and death or transplant listing during the interstage period. Of 610 infants, 39 (6.4%) died or were listed for transplant. In unadjusted analysis, the rate of reaching the primary outcome between SES tertiles was similar (P=0.24). Even after multivariable adjustment, the odds of death or transplant listing were no different for those in the middle (odds ratio, 1.7 [95% CI, 0.73-3.94) or highest (odds ratio, 0.997 [95% CI, 0.30, 3.36]) SES tertile compared with patients in the lowest (overall P value 0.4).

CONCLUSIONS

In a large multicenter cohort of infants with single-ventricle heart disease enrolled in a digital remote monitoring program during the interstage period, we found no difference in outcomes based on SES. Our study suggests that this novel technology could help mitigate differences in outcomes for this fragile population of patients.

Experiences and insights from partners of individuals with single-ventricle CHD: a pilot qualitative research study

INTRODUCTION

With advances in care, an increasing number of individuals with single-ventricle CHD are surviving into adulthood. Partners of individuals with chronic illness have unique experiences and challenges. The goal of this pilot qualitative research study was to explore the lived experiences of partners of individuals with single-ventricle CHD.

METHODS

Partners of patients ≥18 years with single-ventricle CHD were recruited and participated in Experience Group sessions and 1:1 interviews. Experience Group sessions are lightly moderated groups that bring together individuals with similar circumstances to discuss their lived experiences, centreing them as the experts. Formal inductive qualitative coding was performed to identify salient themes.

RESULTS

Six partners of patients participated. Of these, four were males and four were married; all were partners of someone of the opposite sex. Themes identified included uncertainty about their partners' future health and mortality, becoming a lay CHD specialist, balancing multiple roles, and providing positivity and optimism. Over time, they took on a role as advocates for their partners and as repositories of medical history to help navigate the health system. Despite the uncertainties, participants described championing positivity and optimism for the future.

CONCLUSIONS

In this first-of-its-kind pilot study, partners of individuals with single-ventricle CHD expressed unique challenges and experiences in their lives. There is a tacit need to design strategies to help partners cope with those challenges. Further larger-scale research is required to better understand the experiences of this unique population.

The care of the patients with hipoplastic left heart syndrome in places of social and economic vulneability. An ethical analysis

The birth of a child means hope and joy, particularly for the parents and the healthcare team. When this child is born with a severe malformation and a poor prognosis, as in the case of hypoplastic left heart syndrome, the scenario is one of great uncertainty and emotional suffering. The role of the health team becomes fundamental for the identification of conflicts of values and for the search for shared decisions that promote the best benefit to the child. When the diagnosis is made during fetal life, it is necessary to develop counseling strategies appropriate to the context of each family. In places with limited care resources, precarious prenatal care and short temporal conditions, the recommended counseling is compromised. Indication of treatment requires technical competence and a detailed analysis of ethical issues, and consultation with institutional clinical bioethics services or commissions is important. The article proposes to address the moral conflicts of two clinical cases and the respective bioethical analysis that involves principles and values in contexts of vulnerability and uncertainty, contrasting two situations where the indication of treatment was based on accessibility to treatment.

Examining the Real-Life Journey of Individuals and Families Affected by Single-Ventricle Congenital Heart Disease

Background The lifetime journey of patients with single-ventricle congenital heart disease is characterized by long-term challenges that are incompletely understood and still unfolding. Health care redesign requires a thorough understanding of this journey to create and implement solutions that improve outcomes. This study maps the lifetime journey of individuals with single-ventricle congenital heart disease and their families, identifies the most meaningful outcomes to them, and defines significant challenges in the journey. Methods and Results This qualitative research study involved experience group sessions and 1:1 interviews of patients, parents, siblings, partners, and stakeholders. Journey maps were created. The most meaningful outcomes to patients and parents and significant gaps in care were identified across the life journey. A total of 142 participants from 79 families and 28 stakeholders were included. Lifelong and life-stage specific journey maps were created. The most meaningful outcomes to patients and parents were identified and categorized using a "capability (doing the things in life you want to), comfort (experience of physical/emotional pain/distress), and calm (experiencing health care with the least impact on daily life)" framework. Gaps in care were identified and classified into areas of ineffective communication, lack of seamless transitions, lack of comprehensive support, structural deficiencies, and insufficient education. Conclusions There are significant gaps in care during the lifelong journey of individuals with single-ventricle congenital heart disease and their families. A thorough understanding of this journey is a critical first step in developing initiatives to redesign care around their needs and priorities. This approach can be used for people with other forms of congenital heart disease and other chronic conditions. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04613934.

Race-based disparities in access to surgical palliation for hypoplastic left heart syndrome

BACKGROUND

Racial disparities in outcomes have been shown to persist in many operative specialties, including the management of congenital heart disease. Using a demographic-adjusted methodology, we examined whether patient race influenced access to high-performing centers for the operative management of hypoplastic left heart syndrome.

METHODS

The 2005-2017 National Inpatient Sample was queried to identify all pediatric (≤5 years) hospitalizations with an operation for hypoplastic left heart syndrome. A racial disparity index was generated for each hospital and defined as the proportion of White patients receiving operative management for hypoplastic left heart syndrome divided by the proportion of White patients admitted for respiratory failure. This methodology quantified hospital-level racial variation while adjusting for the local racial makeup of each center.

RESULTS

Of the 17,275 patients who met inclusion criteria, 64.1% were managed at high-volume centers. Patients at high-volume centers had a similar distribution of operative type, age, and burden of comorbidities. The mean racial disparity index steadily grew from 1.06 at the lowest volume decile of operative volume to 1.51 at the highest, indicating an increasing proportion of White patients as volume increased. Using risk-adjusted analysis, each decile increase in hospital volume was associated with a 14% relative reduction in odds of mortality and a 0.06 increase in predicted racial disparity index. Increasing volume was further associated with reduced odds of non-home discharge but did not alter resource utilization.

CONCLUSION

We demonstrate that high-volume centers disproportionally serve White patients and have superior clinical outcomes compared to low-volume centers. This study highlights the critical importance of equitable access to expert care for high-risk conditions such as hypoplastic left heart syndrome.

Association of Digoxin With Preserved Echocardiographic Indices in the Interstage Period: A Possible Mechanism to Explain Improved Survival?

Background

For patients with hypoplastic left heart syndrome, digoxin has been associated with reduced interstage mortality after the Norwood operation, but the mechanism of this benefit remains unclear. Preservation of right ventricular (RV) echocardiographic indices has been associated with better outcomes in hypoplastic left heart syndrome. Therefore, we sought to determine whether digoxin use is associated with preservation of the RV indices in the interstage period.

Methods and Results

We conducted a retrospective cohort study of prospectively collected data using the public use data set from the Pediatric Heart Network Single Ventricle Reconstruction trial, conducted in 15 North American centers between 2005 and 2008. We included all patients who survived the interstage period and had echocardiographic data post‐Norwood and pre‐Glenn operations. We used multivariable linear regression to compare changes in RV parameters, adjusting for relevant covariates. Of 289 patients, 94 received digoxin at discharge post‐Norwood. There were no significant differences in baseline clinical characteristics or post‐Norwood echocardiographic RV indices (RV end‐diastolic volume indexed, RV end‐systolic volume indexed, ejection fraction) in the digoxin versus no‐digoxin groups. At the end of the interstage period and after adjustment for relevant covariates, patients on digoxin had better preserved RV indices compared with those not on digoxin for the ΔRV end‐diastolic volume (11 versus 15 mL, P=0.026) and the ΔRV end‐systolic volume (6 versus 9 mL, P=0.009) with the indexed ΔRV end‐systolic volume (11 versus 20 mL/BSA^1.3, P=0.034). The change in the RV ejection fraction during the interstage period between the 2 groups did not meet statistical significance (−2 versus −5, P=0.056); however, the trend continued to be favorable for the digoxin group.

Conclusions

Digoxin use during the interstage period is associated with better preservation of the RV volume and tricuspid valve measurements leading to less adverse remodeling of the single ventricle. These findings suggest a possible mechanism of action explaining digoxin’s survival benefit during the interstage period.

Longitudinal Assessment of Outcome From Prenatal Diagnosis Through Fontan Operation for Over 500 Fetuses With Single Ventricle-Type Congenital Heart Disease: The Philadelphia Fetus-to-Fontan Cohort Study

Background

Prenatal diagnosis of single ventricle‐type congenital heart disease is associated with improved clinical courses. Prenatal counseling allows for optimal delivery preparations and opportunity for prenatal intervention. Expectant parents frequently ask what the likelihood of survival through staged palliation is and the factors that influence outcome. Our goal was specifically to quantify peri‐ and postnatal outcomes in this population.

Methods and Results

We identified all patients with a prenatal diagnosis of single ventricle‐type congenital heart disease presenting between July 2004 and December 2011 at our institution. Maternal data, fetal characteristics, and data from the postnatal clinical course were collected for each patient. Kaplan–Meier curves and multivariate analysis with logistic regression were used to evaluate variables associated with decreased transplant‐free survival. Five hundred two patients were identified, consisting of 381 (76%) right ventricle– and 121 left ventricle–dominant lesions. After prenatal diagnosis, 42 patients did not follow up at our center; 79 (16%) chose termination of pregnancy, and 11 had intrauterine demise with 370 (74%) surviving to birth. Twenty‐two (6%) underwent palliative care at birth. Among 348 surviving to birth with intention to treat, 234 (67%) survived to at least 6 months post‐Fontan palliation. Presence of fetal hydrops, right ventricle dominance, presence of extracardiac anomalies, and low birthweight were significantly associated with decreased transplant‐free survival.

Conclusions

In patients with a prenatal diagnosis of single ventricle‐type congenital heart disease and intention to treat, 67% survive transplant‐free to at least 6 months beyond Fontan operation. An additional 5% survive to 4 years of age without transplant or Fontan completion. Fetuses with right ventricle–dominant lesions, extracardiac anomalies, hydrops, or low birthweights have decreased transplant‐free survival.

Mathematical Analysis and Physical Profile of Blalock-Taussig Shunt and Sano Modification Procedure in Hypoplastic Left Heart Syndrome: Review of the Literature and Implications for the Anesthesiologist

The first stage of surgical treatment for hypoplastic left heart syndrome (HLHS) includes the creation of artificial systemic-to-pulmonary connections to provide pulmonary blood flow. The modified Blalock-Taussig (mBT) shunt has been the technique of choice for this procedure; however, a right ventricle-pulmonary artery (RV-PA) shunt has been introduced into clinical practice with encouraging but still conflicting outcomes when compared with the mBT shunt. The aim of this study is to explore mathematical modeling as a tool for describing physical profiles that could assist the surgical team in predicting complications related to stenosis and malfunction of grafts in an attempt to find correlations with clinical outcomes from clinical studies that compared both surgical techniques and to assist the anesthesiologist in making decisions to manage patients with this complex cardiac anatomy. Mathematical modeling to display the physical characteristics of the chosen surgical shunt is a valuable tool to predict flow patterns, shear stress, and rate distribution as well as energetic performance at the graft level and relative to ventricular efficiency. Such predictions will enable the surgical team to refine the technique so that hemodynamic complications be anticipated and prevented, and are also important for perioperative management by the anesthesia team.

Predicting the Need for Neoaortic Arch Intervention in Infants with Hypoplastic Left Heart Syndrome Through the Glenn Procedure

Neoaortic recoarctation is present in up to over one-third of patients having undergone the Norwood procedure for hypoplastic left heart syndrome. Some of these patients will require reintervention by catheterization or surgery through the time of the Glenn procedure. Echocardiography and catheterization are often utilized in this period to assess hemodynamics although no specific criteria have been identified to predict whether and when neoaortic arch reintervention will be needed. We sought to identify predictors, including but not limited to echocardiographic and catheterization gradients, to predict such intervention. A retrospective analysis was conducted including patients with hypoplastic left heart syndrome. Patients with significantly comorbid lesions such as isomerism, anomalous pulmonary venous connections, and significant atrioventricular valve insufficiency were excluded as were patients without interstage echocardiographic and catheterization data. Receiver operator curve analysis was performed to establish peak-value gradients by echocardiography and catheterization that were predictive of neoaortic reintervention from the time of the Norwood through the time of the Glenn. These values were then entered into a multivariate regression with several other factors to determine what factors were predictive of need for such intervention. Bland-Altman analysis was conducted to compare echocardiographic and catheterization gradients. A peak echocardiographic gradient of 26 mmHg (100 % sensitivity, 85 % specificity) and a peak-to-peak catheterization gradient of 8.5 mm Hg (83 % sensitivity, 86 % specificity) were found to be predictive of need for neoaortic arch reintervention after multivariate analysis. Echocardiographic and catheterization gradients were found to have poor correlation with one another. A peak gradient of 26 mmHg or greater by echocardiography and a peak-to-peak gradient of 8.5 mmHg or greater by catheterization after the Norwood but prior to the Glenn are predictive of need for neoaortic reintervention through the time of the Glenn hospitalization.

Effects of milk flow on the physiological and behavioural responses to feeding in an infant with hypoplastic left heart syndrome

Infants with hypoplastic left heart syndrome often experience difficulty with oral feeding, which contributes to growth failure, morbidity, and mortality. In response to feeding difficulty, clinicians often change the bottle nipple, and thus milk flow rate. Slow-flow nipples have been found to reduce the stress of feeding in other fragile infants, but no research has evaluated the responses of infants with hypoplastic left heart syndrome to alterations in milk flow. The purpose of this study was to evaluate the physiological and behavioural responses of an infant with hypoplastic left heart syndrome to bottle feeding with either a slow-flow (Dr. Brown's Preemie) or a standard-flow (Dr. Brown's Level 2) nipple. A single infant was studied for three feedings: two slow-flow and one standard-flow. Oral feeding, whether with a slow-flow or a standard-flow nipple, was distressing for this infant. During slow-flow feeding, she experienced more coughing events, whereas during standard-flow she experienced more gagging. Disengagement and compelling disorganisation were most common during feeding 3, that is slow-flow, which occurred 2 days after surgical placement of a gastrostomy tube. Clinically significant changes in heart rate, oxygen saturation, and respiratory rate were seen during all feedings. Heart rate was higher during standard-flow and respiratory rate was higher during slow-flow. Further research is needed to examine the responses of infants with hypoplastic left heart syndrome to oral feeding and to identify strategies that will support these fragile infants as they learn to feed. Future research should evaluate an even slower-flow nipple along with additional supportive feeding strategies.

Harnessing Teams and Technology to Improve Outcomes in Infants With Single Ventricle

Infants with single ventricle require staged cardiac surgery, with stage I typically performed shortly after birth, stage II at 4 to 6 months of age, and stage III at 3 to 5 years of age. There is a high risk of interstage mortality and morbidity after infants are discharged from the hospital between stages I and II. Traditional home monitoring requires caregivers to record measurements of weight and oxygen saturation into a binder and requires families to assume a surveillance role. We have developed a tablet PC-based solution that provides secure and nearly instantaneous transfer of patient information to a cloud-based server, with the capacity for instant alerts to be sent to the caregiver team. The cloud-based IT infrastructure lends itself well to being able to be scaled to multiple sites while maintaining strict control over the privacy of each site. All transmitted data are transferred to the electronic medical record daily. The system conforms to recently released Food and Drug Administration regulation that pertains to mobile health technologies and devices. Since this platform was developed in March 2014, 30 patients have been monitored. There have been no interstage deaths. The experience of care providers has been unanimously positive. The addition of video has added to the use of the monitoring program. Of 30 families, 23 expressed a preference for the tablet PC over the notebook, 3 had no preference, and 4 preferred the notebook to the tablet PC.

Risk Factors for Interstage Mortality Following the Norwood Procedure: Impact of Sociodemographic Factors

Interstage mortality remains significant for patients undergoing staged palliation for hypoplastic left heart syndrome and other related single right ventricle malformations (HLV). The purpose of this study was to identify factors related to demographics, socioeconomic position, and perioperative course associated with post-Norwood hospital discharge, pre-stage 2, interstage mortality (ISM). Medical record review was conducted for patients with HLV, born from 1/2000 to 7/2009 and discharged alive following the Norwood procedure. Sociodemographic and perioperative factors were reviewed. Patients were determined to have ISM if they died between Norwood procedure hospital discharge and stage 2 palliation. Univariable and multivariable logistic regressions were performed to identify risk factors associated with ISM. A total of 273 patients were included in the analysis; ISM occurred in 32 patients (12%). Multivariable analysis demonstrated that independent risk factors for interstage mortality included teen mothers [adjusted odds ratio (AOR) 6.6, 95% confidence interval (CI) 1.9-22.5], single adult caregivers (AOR 4.1, 95% CI 1.2-14.4), postoperative dysrhythmia (AOR 2.7, 95% CI 1.1-6.4), and longer ICU stay (AOR 2.7, 95% CI 1.2-6.1). Anatomic and surgical course variables were not associated with ISM in multivariable analysis. Patients with HLV are at increased risk of ISM if born to a teen mother, if they lived in a home with only one adult caregiver, suffered a postoperative dysrhythmia, or experienced a prolonged ICU stay. These risk factors are identifiable, and thus these infants may be targeted for interventions to reduce ISM.

[Hypoplastic left heart syndrome: 10 year experience with staged surgical management]

Hypoplastic left heart syndrome (HLHS) is a lethal congenital heart disease in 95% of non-treated patients. Surgical staging is the main form of treatment, consisting of a 3-stage approach, beginning with the Norwood operation. Long term survival of treated patients is unknown in our country.

OBJECTIVES

1) To review our experience in the management of all patients seen with HLHS between January 2000 and June 2012. 2) Identify risk factors for mortality.

PATIENTS AND METHOD

Retrospective analysis of a single institution experience with a cohort of patients with HLHS. Clinical, surgical, and follow-up records were reviewed.

RESULTS

Of the 76 patients with HLHS, 9 had a restrictive atrial septal defect (ASD), and 8 had an ascending aorta ≤2mm. Of the 65 out of 76 patients that were treated, 77% had a Norwood operation with pulmonary blood flow supplied by a right ventricle to pulmonary artery conduit, 17% had a Norwood with a Blalock-Taussig shunt, and 6% other surgical procedure. Surgical mortality at the first stage was 23%, and for Norwood operation 21.3%. For the period between 2000-2005, surgical mortality at the first stage was 36%, and between 2005-2010, 15% (P=.05). Actuarial survival was 64% at one year, and 57% at 5years. Using a multivariate analysis, a restrictive ASD and a diminutive aorta were high risk factors for mortality.

CONCLUSIONS

Our immediate and long term outcome for staged surgical management of HLHS is similar to that reported by large centres. There is an improvement in surgical mortality in the second half of our experience. Risk factors for mortality are also identified.

Site of interstage care, resource utilization, and interstage mortality: a report from the NPC-QIC registry

Morbidity and mortality remain high for patients with hypoplastic left heart syndrome during the interstage period between Norwood and Glenn despite ongoing QI efforts. We sought to identify associations between the site of interstage care, interstage events, and mortality. Data for patients enrolled in the National Pediatric Cardiology Quality Improvement Collaborative registry from July 2008 through February 2013 were reviewed. Patients had outpatient interstage care at (1) the surgical site (SS) performing Norwood, (2) a non-surgical site (NSS), or (3) a combination. Interstage events were compared among these groups and, when applicable, by distance from SS to NSS. 688 patients from 47 sites met entry criteria. Patients were followed at the SS 411 (60%), NSS 121 (17%), or a combination 143 (21%). Data were not available for 13 (2%). There were 66 deaths (10%) among the entire cohort: 37 (9%) at SS, 13 (11%) at NSS, 15 (10%) at a combination. The proportion of deaths among these groups was not statistically significant (p = 0.60), nor was there a difference based on SS-to-NSS distance. Patients followed at the SS were more likely to have problems detected with feeding (p = 0.03) and breathing (p = 0.002), and ED visits (p < 0.001). The site of interstage care was not associated with mortality, nor was there a difference based on SS-to-NSS distance. Patients followed at the SS had more detected breathing and feeding problems, and ED visits. Further study is required to elucidate the clinical significance of these differences.

Stage one Norwood procedure in an emerging economy:Initial experience in a single center

Objective:

The evolution of surgical skills and advances in pediatric cardiac intensive care has resulted in Norwood procedure being increasingly performed in emerging economies. We reviewed the feasibility and logistics of performing stage one Norwood operation in a limited-resource environment based on a retrospective analysis of patients who underwent this procedure in our institution.

Methods:

Retrospective review of medical records of seven neonates who underwent Norwood procedure at our institute from October 2010 to August 2012.

Results:

The median age at surgery was 9 days (range 5-16 days). All cases were done under deep hypothermic cardiopulmonary bypass and selective antegrade cerebral perfusion. The median cardiopulmonary bypass (CPB) time was 240 min (range 193-439 min) and aortic cross-clamp time was 130 min (range 99-159 min). A modified Blalock-Taussig (BT) shunt was used to provide pulmonary blood flow in all cases. There were two deaths, one in the early postoperative period. The median duration of mechanical ventilation was 117 h (range 71-243 h) and the median intensive care unit (ICU) stay was 12 days (range 5-16 days). Median hospital stay was 30.5 days (range 10-36 days). Blood stream sepsis was reported in four patients. Two patients had preoperative sepsis. One patient required laparotomy for intestinal obstruction.

Conclusions:

Stage one Norwood is feasible in a limited-resource environment if supported by a dedicated postoperative intensive care and protocolized nursing management. Preoperative optimization and prevention of infections are major challenges in addition to preventing early circulatory collapse.

Nutrition algorithms for infants with hypoplastic left heart syndrome; birth through the first interstage period

Failure to thrive is common in infants with hypoplastic left heart syndrome and its variants and those with poor growth may be at risk for worse surgical and neurodevelopmental outcomes. The etiology of growth failure in this population is multifactorial and complex, but may be impacted by nutritional intervention. There are no consensus guidelines outlining best practices for nutritional monitoring and intervention in this group of infants. The Feeding Work Group of the National Pediatric Cardiology Quality Improvement Collaborative performed a literature review and assessment of best nutrition practices from centers participating in the collaborative in order to provide nutritional recommendations and levels of evidence for those caring for infants with single ventricle physiology.

Feeding, growth, nutrition, and optimal interstage surveillance for infants with hypoplastic left heart syndrome

Improvement in operative survival of patients with hypoplastic left heart syndrome has led to increasing emphasis on prevention of interstage mortality. Many centres have improved interstage results through programmes of home monitoring following discharge after the Norwood (Stage 1) operation. Experience with heightened interstage surveillance has identified failure to thrive during infancy as a modifiable risk factor for this population, one that has been linked to concerning outcomes at subsequent palliative surgeries. Ensuring normal growth as an infant has thus become a priority of management of patients with functionally univentricular hearts. Herein, we review the existing evidence for best practices in interstage surveillance and optimal nutrition in infants with functionally univentricular hearts. In addition, we highlight data presented at HeartWeek 2011, from Cardiology 2011, the 15th Annual Update on Pediatric and Congenital Cardiovascular Disease, and the 11th Annual International Symposium on Congenital Heart Disease.

Contemporary management of pulmonary and systemic circulations after the Norwood procedure

Hypoplastic left heart syndrome remains one of the most challenging pathologies in pediatric cardiac surgery. The surgical techniques, and anesthetic and intensive care management, have evolved over the last decades, which has resulted in improved outcomes. A central component in the postoperative management of hypoplastic left heart syndrome patients is to achieve an optimal balance between the pulmonary and systemic circulations. This article discusses the contemporary postoperative management of pulmonary and systemic circulations in detail.

The complex relationship between center volume and outcome in patients undergoing the Norwood operation

BACKGROUND

Norwood outcomes vary across centers, and a relationship between center volume and outcome has been previously described. It is unclear whether this volume-outcome relationship exists across all levels of patient risk or holds true for all centers. We evaluated the impact of patient risk status on the relationship between center volume and outcome, and the extent to which differences in center volume account for between-center variation in outcome.

METHODS

Infants in The Society of Thoracic Surgeons Congenital Heart Surgery Database undergoing the Norwood operation (2000 to 2009) were included. Mortality associated with annual Norwood volume overall and across patient preoperative risk tertiles was evaluated in multivariable analysis. We also estimated the proportion of between-center variation in mortality explained by center volume.

RESULTS

The cohort included 2,557 infants from 53 centers: 34 centers with 0 to 10 Norwood cases per year; 13 centers with 11 to 20 cases per year; and 6 centers with more than 20 cases per year. Unadjusted in-hospital mortality was 22%. In multivariable analysis, lower center volume was associated with higher mortality (odds ratio in low-volume versus high-volume centers 1.54, 95% confidence interval: 1.02 to 2.32, p=0.04). The volume-outcome relationship did not differ across preoperative risk tertiles (p=0.7). Norwood volume explained an estimated 14% of the between-center variation in mortality observed, and significant between-center variation in mortality remained after adjusting for volume (p<0.001).

CONCLUSIONS

Center volume is modestly associated with outcome after the Norwood operation independent of patient risk status. However, this relationship explains only a portion of the between-center variation in mortality in this cohort.

Infants with single ventricle physiology in the emergency department: are physicians prepared?

OBJECTIVE

To assess emergency department (ED) utilization and physician preparedness for infants with single ventricle (SV) physiology between stage 1 and stage 2 surgical palliation.

STUDY DESIGN

Records of infants with SV physiology discharged after stage I palliation between July 2006 and June 2009 were retrospectively reviewed. Next, a cross-sectional survey of registered ED physicians in Michigan was performed.

RESULTS

Thirty-three of 42 patients (79%) required 65 ED visits, most commonly presenting with respiratory distress (35%). Six patients died in the ED; 35 other visits resulted in hospital admission, 4 requiring urgent surgery or catheterization. Median initial hospital stay in those with ED visits was significantly longer (21 days; IQR, 17-45 days) than those without (12 days; IQR, 5.5-24 days) (P = .032). Three hundred seventy-six of 915 surveyed ED physicians responded. Most (72%) were unsure of the acceptable range of arterial oxygen saturation for these infants, and 58% felt "uncomfortable" or "worried" about their treatment. Despite these concerns, 59% deemed education in SV physiology as low priority.

CONCLUSIONS

Between stages I and II, infants with SV physiology utilized the ED frequently, often with high disease acuity. Most ED physicians surveyed appeared underprepared for these infants. These findings underscore the need for educational efforts aimed at increasing ED preparedness.

Tricuspid valve repair in hypoplastic left heart syndrome

Tricuspid valve regurgitation (TR) remains an obstacle for staged palliation of hypoplastic left heart syndrome (HLHS). Because previous results from our institution suggested that posterior leaflet obliteration (PLO) is effective in tricuspid valve repair (TVR), we preferentially used this method. This report analyzes the effect of this preference on repair success and patient survival. All HLHS patients with 3-4+ preoperative TR undergoing TVR between 2002 and 2007 were retrospectively analyzed. Clinical and echocardiographic data were used to determine outcomes. Seventy-one percent (17 of 24) of patients had success at early outcome; the remaining 29% experienced early failure. Sixty-three percent (15 of 24) of patients demonstrated success at late outcome. Early outcome status was found to be a predictor of late outcome status (OR 22.9, P = 0.0037). Overall survival was 71% (17 of 24). Survival could not be shown to be associated with early or late outcome status (odds ratio = 0.96). A preference for PLO was found to give improved, long-lasting results for HLHS patients. Success at immediate outcome was predictive of success with time. PLO has the advantage of being simple and reproducible and produces good outcomes in this challenging group. Continued follow-up will be necessary to confirm long-term outcomes.

Staged surgical palliation in hypoplastic left heart syndrome and its variants

BACKGROUND

Surgical options for infants with hypoplastic left heart syndrome (HLHS) and/or its variants are cardiac transplantation or the heart-preserving staged palliation with Norwood operation,followed by a two-staged Fontan procedure. We describe our 17-year experience with staged palliation of HLHS and/or its variants.

METHODS

Between December 1989 and December 2006, 64 patients with HLHS and/or its variants underwent a Norwood procedure (mean age/weight, 11.8+/-2.5 days/3.4 kg). Forty-four patients had classical HLHS. Twenty-eight percent had associated congenital cardiac, structural, and genetic anomalies. Subsequently, 25 patients underwent a bidirectional Glenn procedure (stage II) and 11 patients a modified Fontan procedure (stage III). Others await stage II and/or stage III. The follow-up was 143.2 patient-years.

RESULTS

Including the learning curve, overall early mortality from 1989 to 1999 after the Norwood procedure was 39.06%. This decreased tremendously for the last seven years, and reduced to 12.8% in 2000 to 2003 until 0% in 2004 to 2006 (p < 0.005). The causes of mortality were sepsis, capillary leak,or heart failure. Three patients died between stages II and III. One patient underwent heart transplantation after the second stage because of heart failure. Among 34 Norwood survivors, four are slightly tachypneic from a mild pulmonary hyperperfusion; one presents symptoms of minimal brain disease.

CONCLUSION

This report identified an outcome improvement after staged palliation of HLHS, attributed to an increase in experience and expertise gained over time. Lower operative weight, ascending aortic size, prolonged duration of cardiopulmonary bypass, and hypothermic circulatory arrest were identified to significantly influence early mortality after the Norwood procedure.

The Norwood procedure using a right ventricle-pulmonary artery conduit: comparison of the right-sided versus left-sided conduit position

OBJECTIVE

We proposed that a right-sided right ventricle-pulmonary artery conduit during the stage I Norwood procedure would facilitate pulmonary artery reconstruction during the stage II procedure.

METHODS

Between 2002 and 2006, 153 patients underwent Norwood stage I reconstruction with a right ventricle-pulmonary artery conduit (125 in the right-sided group and 28 in the left-sided group). The previous 150 consecutive classic Norwood procedures (1997-2002) were used as a control group. Outcomes from stages I and II were analyzed, including ventricular function and pulmonary artery morphology.

RESULTS

The 30-day survival was 88% (110/125) in the right-sided group, 75% (21/28) in the left-sided group, and 70% (105/150) in the control group (P < .001, right-sided vs control groups). The conduit length was 35 +/- 9 mm in the right-sided group and 26 +/- 8 mm in the left-sided group (P = .001). Survival at 6 months demonstrated a significant survival benefit in the right-sided right ventricle-pulmonary artery conduit group over the control group (P = .009, log-rank test). There was no difference in ventricular function between the groups and no regional dyskinesia associated with the right ventricle-pulmonary artery conduit. Despite larger branch pulmonary artery size in the right ventricle-pulmonary artery conduit groups (compared with the control group), central pulmonary artery stenoses were common (62% in the right conduit and 80% in the left conduit). Bypass and ischemic times at stage II were 49 +/- 10 and 23 +/- 13 minutes in the right-sided group compared with 61.5 +/- 9.5 and 31 +/- 14 minutes in the left-sided group (P < .001 and P = .03, respectively). The 30-day mortality after the stage II procedure was 1.3% (1/76) in the right-sided group, 0% (0/18) in the left-sided group, and 3.3% (3/90) in the control group.

CONCLUSION

The right-sided conduit is a safe technique and has improved 30-day and overall post-stage II survival compared with that seen with the classic Norwood procedure. The right ventricle-pulmonary artery conduit is associated with central pulmonary artery stenosis but good development of the branch pulmonary arteries and preservation of ventricular function. The right-sided conduit significantly reduces cardiopulmonary bypass times at stage II.

Impact of antenatal diagnosis of hypoplastic left heart syndrome on the clinical presentation and surgical outcomes: the Australian experience

AIM

Antenatal diagnosis of severe congenital heart disease enables planning of perinatal care of affected infants. Congenital heart surgery is highly centralised in Australia, and surgery for hypoplastic left heart syndrome (HLHS) currently takes place at a single institution, in order to ensure case volume. The study aims to review the impact of antenatal diagnosis on the early clinical course of infants with HLHS in Australia.

METHODS

Retrospective review was performed on all neonates who were admitted for management of HLHS between 2001 and 2005 at the Paediatric Cardiac Surgical Unit, The Royal Children's Hospital, Melbourne, Australia.

RESULTS

Sixty neonates with HLHS were admitted, in whom an antenatal diagnosis was present in 46 (77%). Treatment was withdrawn in seven infants, of whom three had prenatal, and 4 had post-natal diagnoses. Antenatally diagnosed infants were commenced on prostaglandin earlier than post-natally diagnosed infants (age 1 h and 55 h respectively), and on paediatric intensive care unit admission had a higher pH (7.31 vs. 7.20), a lower lactate (3.0 vs. 6.7), a lower inspired oxygen fraction (0.21 vs. 0.96) and were less likely to be ventilated (10.8% vs. 92.9%). Infants with an antenatal diagnosis had lower peak creatinine (70 vs. 120) and alanine aminotransferase (29 vs. 242). The survival to intensive care discharge and stage 2 palliation was 74% and 68% respectively, and was not influenced by timing of diagnosis.

CONCLUSIONS

Antenatal diagnosis of HLHS was strongly associated with a superior pre-operative clinical status, but did not influence early survival after surgical palliation.

B-natriuretic peptide: a helpful clinical marker after Norwood I

Amplified cardiac B-natriuretic peptide (BNP) expression results from ventricular volume or pressure overload. Clinicians have used BNP levels when evaluating cardiac performance in patients with varied clinical conditions. We report a case in which BNP levels helped guide early catheterization intervention in a patient after stage 1 Norwood palliation.

Formation of thrombus in a native aortic sinus of Valsalva after palliation of hypoplastic left heart syndrome

An eight-month-old girl with hypoplastic left heart syndrome, who underwent a modified Norwood operation at the age of two days, and a Hemifontan operation at five months of age, had severely impaired ventricular function and new electrocardiographic changes. Coronary angiography demonstrated a small adherent thrombus in the non-coronary sinus of Valsalva of the native aortic root, which may be the cause of unexplained ventricular dysfunction.

Stage I palliation for hypoplastic left heart syndrome: Norwood versus Sano modification

PURPOSE OF REVIEW

Advancements in surgical technique and perioperative care have significantly improved the survival of infants born with hypoplastic left heart syndrome. A recent modification to the Norwood procedure is being adopted by many centers to improve postoperative hemodynamic stability and survival to stage II palliation. The late effects of this modification, however, are speculated and have not been investigated.

RECENT FINDINGS

Center-specific improved short-term outcomes have been reported in a few small, nonrandomized studies of a new approach to the Norwood procedure, which utilizes a right ventricle to pulmonary artery shunt or Sano modification to provide pulmonary blood flow rather than the standard modified Blalock-Taussig shunt.

SUMMARY

The classic Norwood procedure and Sano modification each have specific advantages and disadvantages in both the short and long term. Data comparing the two techniques are nonrandomized, contradictory, and utilize historical controls. The optimal shunt to improve survival to the second-stage palliation is unknown. A multicenter randomized clinical trial comparing the Sano with the modified Blalock-Taussig shunt in hypoplastic left heart syndrome or variants is currently in progress and should hopefully provide future guidelines for shunt selection based on clinical presentation.

Fate of pulmonary arteries following Norwood Procedure

OBJECTIVE

This study evaluated the requirement for surgical reoperation and catheter-based reintervention to central pulmonary arteries (CPAs) following Norwood Procedure (NP). We sought to identify the influence of various surgical techniques employed during NP on subsequent interventions.

METHODS

Between 1993 and 2004, 226 patients underwent Stage II following NP. Ninety-eight patients (43%) had completion of Fontan circulation (Stage III) and a further 107 (47%) are on course for Fontan completion with 21 (9%) inter-stage deaths. During NP, the aortic arch was reconstructed without additional material (n = 91, 40%) or with a pulmonary homograft patch (n = 135, 60%). Pulmonary blood flow was supplied by modified Blalock-Taussig shunt (n = 177, 78%) or right ventricle to pulmonary artery conduit (RV-PA; n = 49, 22%). The CPAs defect was closed directly (n = 69, 31%) or with a patch (n = 157, 69%). Complete resection of coarctation was performed in 126 patients (56%).

RESULTS

Ninety-seven patients (43%) required surgical reoperation to CPAs during Stage II. Actuarial freedom from reoperation was 60+/-3%, 52+/-4% and 50+/-4% at 1, 5 and 10 years, respectively. On multivariable analysis, NP with RV-PA increased risk of reoperation (LR 8.3, 5.3-13.2; p < 0.001). Forty-one patients (18%) required catheter-based reintervention on CPAs. Actuarial freedom from reintervention was 98+/-1%, 72+/-4% and 58+/-6% at 1, 5 and 10 years, respectively. CPA problems were almost exclusively limited to the proximal Left pulmonary artery. On multivariable analysis, catheter-based reintervention became more common with time. Complete resection of coarctation increased risk of reintervention (LR 3.9, 1.6-9.6; p < 0.005). Arch reconstruction and CPAs repair techniques did not affect risk of reoperation or reintervention on CPAs.

CONCLUSIONS

CPA stenoses and hypoplasia need surgical attention in approximately half of all patients undergoing the NP. The need for reoperation is increased when using the RV-PA conduit technique (although the majority of these are performed as part of the Stage II procedure). Catheter reinterventions are almost exclusively confined to the left CPA and are increased when the arch is shortened by resection of the coarctation tissue at time of NP.

Impact of preoperative treatment strategies on the early perioperative outcome in neonates with hypoplastic left heart syndrome

OBJECTIVE

This study was undertaken to determine the impact of specific intensive care procedures on preoperative hemodynamics, incidence of preoperative organ dysfunction, and in-hospital mortality among neonates with hypoplastic left heart syndrome with pulmonary overcirculation and to assess the influence of the change in preoperative management on early postoperative outcome.

METHODS

In this retrospective evaluation of 72 neonates with classic hypoplastic left heart syndrome and severe pulmonary overcirculation with different preoperative management strategies from 1992 to 1995 and from 1996 to 2000, univariate and multivariate analyses of risk factors were performed with stepwise logistic regression.

RESULTS

Among patients with ventilatory and inotropic support from admission until surgery, degree of metabolic acidosis (lowest recorded and prerepair pH values) was significantly higher than among patients who received systemic vasodilators without ventilation before surgery. Preoperative organ dysfunction occurred in 19 of 72 patients (26%), predominantly before 1996; the most significant was hepatic failure in 13 (68%). Lowest recorded and prerepair pH values did not predict the development of organ dysfunction, whereas inotropic medication, lack of afterload reduction, and especially ventilatory support correlated significantly with organ injury. In-hospital mortality decreased from 65% (13/20) to 13% (6/46) from the first to the second period. According to multivariate analysis, ventilatory support and organ dysfunction were significantly related to in-hospital mortality.

CONCLUSION

In neonates with hypoplastic left heart syndrome, systemic afterload reduction can avoid preoperative artificial respiration, identified as a significant risk factor for the development of preoperative dysfunction of end organs and in-hospital mortality.

Influence of surgical strategies on outcome after the Norwood procedure

OBJECTIVE

The study objective was to identify how the evolution of surgical strategies influenced the outcome after the Norwood procedure.

METHODS

From 1992 to 2004, 367 patients underwent the Norwood procedure (median age, 4 days). Three surgical strategies were identified on the basis of arch reconstruction and source of pulmonary blood flow. The arch was refashioned without extra material in group A (n = 148). The arch was reconstructed with a pulmonary artery homograft patch in groups B (n = 145) and C (n = 74). Pulmonary blood flow was supplied by a modified Blalock-Taussig shunt in groups A and B. Pulmonary blood flow was supplied by a right ventricle to pulmonary artery conduit in group C. Early mortality, actuarial survival, and freedom from arch reintervention or pulmonary artery patch augmentation were analyzed.

RESULTS

Early mortality was 28% (n = 102). Actuarial survival was 62% +/- 3% at 6 months. Early mortality was lower in group C (15%) than group A (31%) or group B (31%; P <.05). Actuarial survival at 6 months was better in group C (78% +/- 5%) than group A (59% +/- 5%) or group B (58% +/- 4%; P <.05). Fifty-three patients (14%) had arch reintervention. Freedom from arch reintervention was 76% +/- 3% at 1 year, with univariable analysis showing no difference among groups A, B, and C (P =.71). One hundred patients (27%) required subsequent pulmonary artery patch augmentation. Freedom from patch augmentation was 61% +/- 3% at 1 year, and was lower in group C (3% +/- 3%) than group A (80% +/- 4%) or group B (72% +/- 5%; P <.05).

CONCLUSIONS

Survival after the Norwood procedure improved after the introduction of a right ventricle to pulmonary artery conduit, but a greater proportion of patients required subsequent pulmonary artery patch augmentation. The type of arch reconstruction did not affect the incidence of arch reintervention.

Optimal timing of the second stage of palliation for hypoplastic left heart syndrome facilitated through home monitoring, and the results of early cavopulmonary anastomosis

For children with hypoplastic left heart syndrome, contemporary management over three stages includes a window of high risk for sudden death between the initial stage of palliation, the Norwood operation itself, and the second stage, creation of the bidirectional superior cavopulmonary connection. The risk is highest at a time when patients have been discharged from the hospital to grow and prepare for the second stage,1–4and has persisted despite the remarkable improvements in immediate postoperative and hospital survival after the initial surgery.5,6Potential contributing factors to the increased vulnerability to sudden death between the stages include the limited circulatory reserve inherent in the parallel circulations supported by a functionally univentricular heart, the reliance on a prosthetic shunt which is susceptible to thrombosis, and congenital or acquired anatomical cardiovascular abnormalities such as aortic atresia, residual obstruction in the aortic arch, tricuspid valvar insufficiency, or right ventricular dysfunction.7–12

Staged surgical management of hypoplastic left heart syndrome: a single institution 12 year experience

OBJECTIVE

To describe a 12 year experience with staged surgical management of the hypoplastic left heart syndrome (HLHS) and to identify the factors that influenced outcome.

METHODS

Between December 1992 and June 2004, 333 patients with HLHS underwent a Norwood procedure (median age 4 days, range 0-217 days). Subsequently 203 patients underwent a bidirectional Glenn procedure (stage II) and 81 patients underwent a modified Fontan procedure (stage III). Follow up was complete (median interval 3.7 years, range 32 days to 11.3 years).

RESULTS

Early mortality after the Norwood procedure was 29% (n = 95); this decreased from 46% (first year) to 16% (last year; p < 0.05). Between stages, 49 patients died, 27 before stage II and 22 between stages II and III. There were one early and three late deaths after stage III. Actuarial survival (SEM) was 58% (3%) at one year and 50% (3%) at five and 10 years. On multivariable analysis, five factors influenced early mortality after the Norwood procedure (p < 0.05). Pulmonary blood flow supplied by a right ventricle to pulmonary artery (RV-PA) conduit, arch reconstruction with pulmonary homograft patch, and increased operative weight improved early mortality. Increased periods of cardiopulmonary bypass and deep hypothermic circulatory arrest increased early mortality. Similar factors also influenced actuarial survival after the Norwood procedure.

CONCLUSION

This study identified an improvement in outcome after staged surgical management of HLHS, which was primarily attributable to changes in surgical technique. The RV-PA conduit, in particular, was associated with a notable and independent improvement in early and actuarial survival.

Late Left Pulmonary Artery Stenosis After the Norwood Procedure is Prevented by a Modification in Shunt Construction

BACKGROUND

Late left pulmonary artery (LPA) stenosis occurs commonly after the Norwood procedure, and complicates subsequent stages. Compression by the neoaorta and ductal stump may favor flow into the right pulmonary artery, resulting in LPA hypoplasia. We hypothesize that an early compromise of LPA flow contributes to late LPA stenosis, and have modified our shunt to compensate.

METHODS

We reviewed 34 consecutive neonates undergoing the Norwood procedure between 1999 and 2002, and morphometric data from angiograms obtained before the bidirectional cavopulmonary anastomosis (BDCPA). The Norwood technique included an autologous arch reconstruction with or without augmentation, and a polytetrafluoroethylene Blalock-Taussig shunt (BTS). Starting February 2001, the distal shunt was modified from an end-to-side construction to an oblique anastomosis directed into the retroaortic LPA.

RESULTS

Norwood survival was 82%. LPA stenosis required plasty in 10 of 13 (77%) premodification survivors, and in 2 of 9 (22%) postmodification (p = 0.027). Bypass time was 151 +/- 65 minutes with LPA plasty versus 95 +/- 50 minutes without. Mortality (15% vs 0%), hospital stay (25 +/- 35 vs 9 +/- 6 days), and incidence of subsequent interventions were correspondingly higher with LPA stenosis. Ten of 13 patients (77%) with a BTS insertion point outside the central region of the pulmonary artery required LPA plasty, versus 2 of 9 (22%) with an insertion nearer to the center (p = 0.027).

CONCLUSIONS

An oblique distal BTS anastomosis directed leftward onto the retroaortic pulmonary artery at the time of the Norwood procedure may prevent late LPA stenosis and its attendant morbidity.

The effect of surgical case volume on outcome after the Norwood procedure

OBJECTIVES

We analyze the effect of surgical case volume on the survival of infants with hypoplastic left heart syndrome who underwent stage I surgical palliation (the Norwood procedure). The purpose of our study was to understand more clearly the relative effects of institution and surgeon experience on patient outcome.

METHODS

Using the Pediatric Health Information System database belonging to the pediatric hospital members of the Child Health Corporation of America, we identified newborn infants (< 30 days old on admission) from 1998 through 2001 admitted with the diagnosis of hypoplastic left heart syndrome. Stepwise multiple regression analysis was used to examine the association between both institutional and surgeon case volume with 28-day survival after the Norwood procedure.

RESULTS

Twenty-nine hospitals and 87 surgeons performed 801 Norwood procedures during the study period. In the 4 of 29 institutions that averaged 1 or more Norwood procedures per month during the study period, survival averaged 78%. The remaining 25 institutions averaged 1 Norwood procedure every 9.6 weeks, with a survival of 59%. Data analysis revealed that higher institutional volume (P = .02) but not the number of cases performed by surgeons (P = .13) increased survival after the Norwood procedure. There was no such association with average length of stay in survivors or the time to mortality in nonsurvivors.

CONCLUSION

Survival after the Norwood procedure is associated with institutional Norwood procedure volume but not with individual surgeon case volume, suggesting the need for improvements in institutional-based approaches to the care of children with hypoplastic left heart syndrome and the need for establishing regional referral centers for such high-risk procedures to improve patient survival.

Home monitoring of infants after stage one palliation for hypoplastic left heart syndrome

Despite improved early results with the Norwood procedure (stage one palliation), patients remain with at-risk anatomy and interstage mortality continues to be a limitation of staged single ventricle palliation. Retrospective analyses have implicated residual or recurrent anatomic lesions as well as intercurrent illness as causes of interstage mortality. We hypothesized that potentially life-threatening anatomic lesions and illnesses would be manifest before serious physiologic impact by alteration in arterial saturation, failure to gain weight or in the case of dehydration, acute weight loss. As a result, we developed a home monitoring program of daily weights and oxygen saturations to earlier identify those patients at increased risk for interstage death. Frequent monitoring of these physiologic variables between stage one and two palliation identified life-threatening anatomic lesions and illness and permitted timely intervention that ultimately improved survival. All 36 survivors of the stage one palliation discharged from the hospital and entered into the home monitoring program survived the interstage period.

Single-ventricle physiology: perioperative implications

Neonates with functional single ventricles have pulmonary and systemic circulations that are supplied in parallel, creating significant cyanosis and ventricular volume overload. The goal of palliative surgery, excluding transplantation, is to convert single-ventricle circulation from a parallel to a series arrangement. This will ultimately require a complete cavopulmonary anastomosis (Fontan-type procedure) in which vena caval blood is rerouted directly into the pulmonary circulation. Various factors require that this palliation occur in stages. Stage I surgery, which is often a Norwood procedure, is done in the neonatal period and stabilizes, but does not resolve, parallel circulation. The tenuous balance between pulmonary and systemic perfusion during this stage makes noncardiac surgery hazardous, and it should be restricted to urgent or emergent indications. Stage II surgery, or partial cavopulmonary anastomosis, relieves both parallel circulation and volume overload, but not cyanosis. Relatively stable hemodynamics during this stage create favorable conditions for elective surgery. Patients who have undergone stage III surgery, the Fontan-type repair, vary in age from toddlers to adults, and in physical status from well-compensated to significantly debilitated. Fontan patients require thorough preoperative assessment when elective surgery is contemplated. Optimal communication between surgeons, anesthesiologists, and cardiologists is essential when caring for the patient with single-ventricle physiology.

The low resistance strategy for the perioperative management of the Norwood procedure

BACKGROUND

Postoperative course of the Norwood procedure is fragile because of an unstable pulmonary to systemic blood flow ratio caused by fluctuation of systemic and pulmonary vascular resistance.

METHODS

Twenty-seven patients with hypoplastic left heart syndrome who underwent the Norwood procedure from June 1998 to February 2002 were managed with the following low-resistance strategy. Intraoperative high-flow and low-resistance cardiopulmonary bypass was achieved with total avoidance of circulatory arrest and a large dose of chlorpromazine. In weaning from the bypass, pulmonary vascular resistance was maximally decreased by inspired oxygen fraction (100%), inhaled nitric oxide (20 ppm), and nitroglycerin (2 to 4 microg/kg/min). Then pulmonary blood flow was determined by adjusting the systemic to pulmonary shunt. Postoperatively, with continuous infusion of chlorpromazine and nitroglycerin as a systemic and pulmonary vasodilator, the inspired oxygen fraction and inhaled nitric oxide were tapered as the arterial oxygen saturation improved.

RESULTS

In most patients, inhaled nitrous oxide and inspired oxygen fraction were weaned within 3 days. The postoperative course was stable with minimum changes in circulatory and respiratory status for the survivors. Patients were extubated on a median of 6 postoperative days. Early mortality was 11.1% (3 of 27), and none of the patients died of hemodynamic deterioration.

CONCLUSIONS

The low resistance strategy is a simple and useful method for perioperative management of the Norwood procedure, minimizing fluctuation in both pulmonary and systemic vascular resistance and maintaining stable circulatory and respiratory status.

Neonatal physiology of the functionally univentricular heart

The neonate with functionally univentricular physiology presents unique challenges to the cardiac team. An integrated approach that applies working knowledge of cardiac anatomy, cardiopulmonary physiology, and basic principles of intensive care is essential to guide management of each individual patient. This requires cooperative and constructive involvement of a surgical, medical, nursing and respiratory care team experienced in the management of such patients. In the neonate with this physiology, systemic oxygen delivery is optimized by manipulating pulmonary and systemic resistances, augmenting total cardiac output, and utilizing strategies for ventilation that preserve optimal pulmonary recruitment.

Effect of a selection and postoperative care protocol on survival of infants with hypoplastic left heart syndrome

BACKGROUND

We report the development and implementation of a program designed to assign patients preoperatively to either transplant or Norwood procedure based on a score derived from known risk factors and to enhance postoperative care of infants undergoing the Norwood procedure.

METHODS

A weighted score for each of six variables comprised the scoring system: ventricular function, tricuspid regurgitation, ascending aortic diameter, atrial septal defect blood flow characteristics, blood type, and age. The scoring system was used to prospectively assign mortality risk and lead to recommendation of either Norwood procedure or transplantation.

RESULTS

Survival following the Norwood procedure significantly improved after the management program was implemented (88% versus 40% at 48 hours, 57% versus 10% at 30 days, and 50% versus 10% at 1 year, p < 0.0001 at each time point). The survival of the group that received a score of 7 or less (high risk) who underwent the Norwood procedure was 78% at 48 hours, 44% at 30 days, and 33% at 1 year; survival rates among patients considered lower risk (greater than 7) were 100% at 48 hours and 80% at 30 days and 1 year. Transplant outcomes remained unchanged.

CONCLUSIONS

We report improved survival following the Norwood procedure after the implementation of an institutional management approach aimed at improving the outcome of infants with hypoplastic left heart syndrome and may help neutralize historical biases toward Norwood procedure or transplantation.

Right ventricular to pulmonary artery conduit instead of modified Blalock-Taussig shunt improves postoperative hemodynamics in newborns after the Norwood operation

OBJECTIVE

Perioperative mortality, prolonged postoperative recovery after the Norwood procedure, and mortality between stage I and stage II might be related to shunt physiology. A right ventricular to pulmonary artery conduit offers a banded physiology in contrast to a Blalock-Taussig shunt. The purpose of this study was to assess the hemodynamic differences and their consequences in the postoperative course between Norwood patients with a Blalock-Taussig shunt and those with a right ventricular to pulmonary artery conduit.

METHODS

From October 1999 until May 2002, 32 unselected consecutive patients underwent a Norwood procedure at the General Hospital Linz. The first 18 patients received a Blalock-Taussig shunt. In the remaining 14 patients we performed a right ventricular to pulmonary artery conduit. Both groups were compared.

RESULTS

The diastolic blood pressure was significantly higher in the right ventricular to pulmonary artery conduit group (P <.001). Despite a higher FIO(2), PO(2) levels tended to be lower in the first 5 postoperative days. At the age of 3 months, catheterization laboratory data showed a lower Qp/Qs ratio in the same group (0.86 [0.78; 1] versus 1.55 [1.15; 1.6]; P =.005) and a higher dp/dt (955 [773; 1110] vs 776 [615; 907]; P =.018). (Descriptive data reflect medians and quartiles [in brackets].) Hospital survival was 72% in the Blalock-Taussig shunt group versus 93% in the right ventricular to pulmonary artery conduit group. Mortality between stage I and stage II was 23% in the Blalock-Taussig shunt group versus 0% in the right ventricular to pulmonary artery conduit group.

CONCLUSIONS

A higher diastolic blood pressure and a lower Qp/Qs ratio were associated with a more stable and efficient circulation in patients with a right ventricular to pulmonary artery conduit. More intensive ventilatory support was necessary during the first postoperative days. We did not note any adverse effects of the ventriculotomy on ventricular performance.

Home surveillance program prevents interstage mortality after the Norwood procedure

OBJECTIVE

To determine whether early identification of physiologic variances associated with interstage death would reduce mortality, we developed a home surveillance program.

METHODS

Patients discharged before initiation of home surveillance (group A, n = 63) were compared with patients discharged with an infant scale and pulse oximeter (group B, n = 24). Parents maintained a daily log of weight and arterial oxygen saturation according to pulse oximetry and were instructed to contact their physician in case of an arterial oxygen saturation less than 70% according to pulse oximetry, an acute weight loss of more than 30 g in 24 hours, or failure to gain at least 20 g during a 3-day period.

RESULTS

Interstage mortality among infants surviving to discharge was 15.8% (n = 9/57) in group A and 0% (n = 0/24) in group B (P =.039). Surveillance criteria were breached for 13 of 24 group B patients: 12 patients with decreased arterial oxygen saturation according to pulse oximetry with or without poor weight gain and 1 patient with poor weight gain alone. These 13 patients underwent bidirectional superior cavopulmonary connection (stage 2 palliation) at an earlier age, 3.7 +/- 1.1 months of age versus 5.2 +/- 2.0 months for patients with an uncomplicated interstage course (P =.028). A growth curve was generated and showed reduced growth velocity between 4 and 5 months of age, with a plateau in growth beyond 5 months of age.

CONCLUSION

Daily home surveillance of arterial oxygen saturation according to pulse oximetry and weight selected patients at increased risk of interstage death, permitting timely intervention, primarily with early stage 2 palliation, and was associated with improved interstage survival. Diminished growth identified 4 to 5 months after the Norwood procedure brings into question the value of delaying stage 2 palliation beyond 5 months of age.