Risk factors for hospital morbidity and mortality after the Norwood procedure: A report from the Pediatric Heart Network Single Ventricle Reconstruction trial

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.

Hybrid stage 1 palliation for HLHS: the experience of a tertiary center in a developing country

Background

Hypoplastic left heart syndrome (HLHS) accounts for 2.6% of congenital heart disease and is an invariably fatal cardiac anomaly if left untreated. Approximately 33,750 babies are born annually with HLHS in developing countries. Unfortunately, the majority will not survive due to the scarcity of resources and the limited availability of surgical management.

Aim

To describe and analyze our experience with the hybrid approach in the management of HLHS in a developing country.

Methods

We performed a retrospective single-center study involving all neonates born with HLHS over five years at the Children's Heart Center at the American University of Beirut. The medical records of patients who underwent the hybrid stage 1 palliation were reviewed, and data related to baseline characteristics, procedure details and outcomes were collected to describe the experience at a tertiary care center in a developing country.

Results

A total of 18 patients were diagnosed with HLHS over a five-year period at our institution, with male to female ratio of 1:1. Of those, eight patients underwent the hybrid stage I procedure. The mean weight at the time of the procedure was 3.3 ± 0.3 kg with an average age of 6.4 ± 4 days. The mean hospital length of stay was 27.25 days, with an interquartile range of 33 days. The cohort's follow-up duration averaged 5.9 ± 3.5 years. The surgical mortality was zero. Only one mortality was recorded during the interstage period between stage I and II and was attributed to sepsis. Notably, all surviving patients maintained preserved and satisfactory cardiac function with good clinical status.

Conclusion

Our limited experience underscores the potential of developing countries with proper foundations to adopt the hybrid procedure for HLHS, yielding outcomes on par with those observed in developed countries. This demonstrates the viability of establishing a more balanced global landscape for children with congenital heart disease.

Days alive and out of hospital for children born with single-ventricle heart disease

BACKGROUND

This study describes the illness burden in the first year of life for children with single-ventricle heart disease, using the metric of days alive and out of hospital to characterize morbidity and mortality.

METHODS

This is a retrospective single-centre study of single-ventricle patients born between 2005 and 2021 who had their initial operation performed at our institution. Patient demographics, anatomical details, and hospitalizations were extracted from our institutional single-ventricle database. Days alive and out of hospital were calculated by subtracting the number of days hospitalized from number of days alive during the first year of life. A multivariable linear regression with stepwise variable selection was used to determine independent risk factors associated with fewer days alive and out of hospital.

RESULTS

In total, 437 patients were included. Overall median number of days alive and out of hospital in the first year of life for single-ventricle patients was 278 days (interquartile range 157-319 days). In a multivariable analysis, low birth weight (<2.5kg) (b = -37.55, p = 0.01), presence of a dominant right ventricle (b = -31.05, p = 0.01), moderate-severe dominant atrioventricular valve regurgitation at birth (b = -37.65, p < 0.05), index hybrid Norwood operation (b = -138.73, p < 0.01), or index heart transplant (b = -158.41, p < 0.01) were all independently associated with fewer days alive and out of hospital.

CONCLUSIONS

Children with single-ventricle heart defects have significant illness burden in the first year of life. Identifying risk factors associated with fewer days alive and out of hospital may aid in counselling families regarding expectations and patient prognosis.

Using machine learning to predict five-year transplant-free survival among infants with hypoplastic left heart syndrome

Hypoplastic left heart syndrome (HLHS) is a congenital malformation commonly treated with palliative surgery and is associated with significant morbidity and mortality. Risk stratification models have often relied upon traditional survival analyses or outcomes data failing to extend beyond infancy. Individualized prediction of transplant-free survival (TFS) employing machine learning (ML) based analyses of outcomes beyond infancy may provide further valuable insight for families and healthcare providers along the course of a staged palliation. Data from both the Pediatric Heart Network (PHN) Single Ventricle Reconstruction (SVR) trial and Extension study (SVR II), which extended cohort follow up for five years was used to develop ML-driven models predicting TFS. Models incrementally incorporated features corresponding to successive phases of care, from pre-Stage 1 palliation (S1P) through the stage 2 palliation (S2P) hospitalization. Models trained with features from Pre-S1P, S1P operation, and S1P hospitalization all demonstrated time-dependent area under the curves (td-AUC) beyond 0.70 through 5 years following S1P, with a model incorporating features through S1P hospitalization demonstrating particularly robust performance (td-AUC 0.838 (95% CI 0.836-0.840)). Machine learning may offer a clinically useful alternative means of providing individualized survival probability predictions, years following the staged surgical palliation of hypoplastic left heart syndrome.

Bilateral pulmonary artery banding in higher risk neonates with hypoplastic left heart syndrome

Objectives

Limited data on performing bilateral pulmonary artery banding (BPAB) before stage 1 Norwood procedure suggest that some patients may benefit through the postponement of the major cardiopulmonary bypass procedure. The objective of this study was to evaluate the effectiveness of BPAB in the surgical management of high-risk patients with hypoplastic left heart syndrome (HLHS).

Methods

A retrospective review of all high-risk neonates with HLHS who underwent BPAB at our institution was performed. No patients, including those with intact or highly restrictive atrial septum (IAS), were excluded.

Results

Between October 2015 and April 2021, 49 neonates with HLHS (including 6 with IAS) underwent BPAB, 40 of whom progressed to the Norwood procedure. Risk factors for not progressing to the Norwood procedure after BPAP include low birth weight (P = .043), the presence of multiple extracardiac anomalies (P = .005), and the presence of genetic disorders (P = .028). Operative mortality was 7.5% (3/40). IAS was associated with operative mortality (P = .022).

Conclusions

The strategy of BPAB prestage 1 Norwood procedure was successful in identifying at-risk patients and improving Norwood survival. Although not all patients will need this hybrid approach, a significant number can be expected to benefit from this tactic. These results support the need for a substantial hybrid strategy, in addition to a primary stage 1 Norwood surgical strategy, in the management of HLHS.

Transcatheter Palliation With Pulmonary Artery Flow Restrictors in Neonates With Congenital Heart Disease: Feasibility, Outcomes, and Comparison With a Historical Hybrid Stage 1 Cohort

BACKGROUND

Neonates with complex congenital heart disease and pulmonary overcirculation have been historically treated surgically. However, subcohorts may benefit from less invasive procedures. Data on transcatheter palliation are limited.

METHODS

We present our experience with pulmonary flow restrictors (PFRs) for palliation of neonates with congenital heart disease, including procedural feasibility, technical details, and outcomes. We then compared our subcohort of high-risk single ventricle neonates palliated with PFRs with a similar historical cohort who underwent a hybrid Stage 1. Cox regression was used to evaluate the association between palliation strategy and 6-month mortality.

RESULTS

From 2021 to 2023, 17 patients (median age, 4 days; interquartile range [IQR], 2-8; median weight, 2.5 kilograms [IQR, 2.1-3.3]) underwent a PFR procedure; 15 (88%) had single ventricle physiology; 15 (88%) were high-risk surgical candidates. All procedures were technically successful. At a median follow-up of 6.2 months (IQR, 4.0-10.8), 13 patients (76%) were successfully bridged to surgery (median time since PFR procedure, 2.6 months [IQR, 1.1-4.4]; median weight, 4.9 kilograms [IQR, 3.4-5.8]). Pulmonary arteries grew adequately for age, and devices were easily removed without complications. The all-cause mortality rate before target surgery was 24% (n=4). Compared with the historical hybrid stage 1 cohort (n=23), after adjustment for main confounding (age, weight, intact/severely restrictive atrial septum or left ventricle to coronary fistulae), the PFR procedure was associated with a significantly lower all-cause 6-month mortality risk (adjusted hazard ratio, 0.26 [95% CI, 0.08-0.82]).

CONCLUSIONS

Transcatheter palliation with PFR is feasible, safe, and represents an effective strategy for bridging high-risk neonates with congenital heart disease to surgical palliation, complete repair, or transplant while allowing for clinical stabilization and somatic growth.

Combined ventricular dysfunction and atrioventricular valve regurgitation after the Norwood procedure are associated with attrition prior to superior cavopulmonary connection

Background

Infants with hypoplastic left heart syndrome (HLHS) or a variant are at risk of ventricular dysfunction (VD) and atrioventricular valve regurgitation (AVVR) prior to superior cavopulmonary connection (SCPC). Although the impact of these complications in isolation has been described, their effect in combination on attrition is poorly defined.

Methods

A retrospective observational study of patients with HLHS or variants undergoing a Norwood procedure between 2008 and 2020 at a single center was performed. VD and AVVR were defined as moderate or severe when seen on 2 sequential echocardiograms outside the perioperative period. Attrition was defined as death, listing for heart transplant, or unsuitability for SCPC or transplant. Descriptive statistics and regression models were used for analysis.

Results

A total of 397 patients were included, of whom 75% had HLHS and 57% had received a Blalock-Thomas-Taussig shunt. Isolated VD occurred in 9% of patients, AVVR occurred in 13%, and both occurred in 6%. Attrition prior to SCPC occurred in 19% of the overall cohort, in 52% of patients with combined VD and AVVR (odds ratio [OR], 5.2; 95% confidence interval [CI], 2.3-12.0; P < .01), 26% of those with VD (OR, 1.5; 95% CI, 0.7-3.3; P = .32), 25% of those with AVVR (OR, 1.5; 95% CI, 0.7-2.9; P = .27), and 15% in those with neither (OR, 0.3; 95% CI, 0.2-0.6; P < .01). Other factors associated with attrition included prematurity, total bypass time at Norwood, and extracorporeal membrane oxygenation after Norwood, whereas later year of Norwood was protective (P < .01 for all).

Conclusions

The presence of combined VD and AVVR markedly increases the likelihood of attrition prior to SCPC, identifying a high-risk group.

The NEONATE score predicts freedom from interstage mortality or transplant in a modern cohort

BACKGROUND

Derived from the National Pediatric Cardiology Quality Improvement Collaborative registry, the NEONATE risk score predicted freedom from interstage mortality or heart transplant for patients with single ventricle CHD and aortic arch hypoplasia discharged home following Stage 1 palliation.

OBJECTIVES

We sought to validate the score in an external, modern cohort.

METHODS

This was a retrospective cohort analysis of single ventricle CHD and aortic arch hypoplasia patients enrolled in the National Pediatric Cardiology Quality Improvement Collaborative Phase II registry from 2016 to 2020, who were discharged home after Stage 1 palliation. Points were allocated per the NEONATE score (Norwood type-Norwood/Blalock-Taussig shunt: 3, Hybrid: 12; extracorporeal membrane oxygenation post-op: 9, Opiates at discharge: 6, No Digoxin at discharge: 9, Arch Obstruction on discharge echo: 9, Tricuspid regurgitation ≥ moderate on discharge echo: 12; Extra oxygen plus ≥ moderate tricuspid regurgitation: 28). The composite primary endpoint was interstage mortality or heart transplant.

RESULTS

In total, 1026 patients met inclusion criteria; 61 (6%) met the primary outcome. Interstage mortality occurred in 44 (4.3%) patients at a median of 129 (IQR 62,195) days, and 17 (1.7%) were referred for heart transplant at a 167 (114,199) days of life. The median NEONATE score was 0(0,9) in those who survived to Stage 2 palliation compared to 9(0,15) in those who experienced interstage mortality or heart transplant (p < 0.001). Applying a NEONATE score cut-off of 17 points that separated patients into low- and high-risk groups in the learning cohort provided 91% specificity, negative predictive value of 95%, and overall accuracy of 87% (85.4-89.5%).

CONCLUSION

In a modern cohort of patients with single ventricle CHD and aortic arch hypoplasia, the NEONATE score remains useful at discharge post-Stage 1 palliation to predict freedom from interstage mortality or heart transplant.

Center-level factors associated with shorter length of stay following stage 1 palliation: An analysis of the national pediatric cardiology quality improvement collaborative registry

BACKGROUND

Stage 1 single ventricle palliation (S1P) has the longest length of stay (LOS) of all benchmark congenital heart operations. Center-level factors contributing to prolonged hospitalization are poorly defined.

METHODS

We analyzed data from infants status post S1P included in the National Pediatric Cardiology Quality Improvement Collaborative Phase II registry. Our primary outcome was patient-level LOS with days alive and out of hospital before stage 2 palliation (S2P) used as a balancing measure. We compared patient and center-level characteristics across quartiles for median center LOS, and used multivariable regression to calculate center-level factors associated with LOS after adjusting for case mix.

RESULTS

Of 2,510 infants (65 sites), 2037 (47 sites) met study criteria (61% male, 61% white, 72% hypoplastic left heart syndrome). There was wide intercenter variation in LOS (first quartile centers: median 28 days [IQR 19, 46]; fourth quartile: 62 days [35, 95], P < .001). Mortality prior to S2P did not differ across quartiles. Shorter LOS correlated with more pre-S2P days alive and out of hospital, after accounting for readmissions (correlation coefficient -0.48, P < .001). In multivariable analysis, increased use of Norwood with a right ventricle to pulmonary artery conduit (aOR 2.65 [1.1, 6.37]), shorter bypass time (aOR 0.99 per minute [0.98,1.0]), fewer additional cardiac operations (aOR 0.46 [0.22, 0.93]), and increased use of NG tubes rather than G tubes (aOR 7.03 [1.95, 25.42]) were all associated with shorter LOS centers.

CONCLUSIONS

Modifiable center-level practices may be targets to standardize practice and reduce overall LOS across centers.

Longitudinal Follow-Up of Children With HLHS and Association Between Norwood Shunt Type and Long-Term Outcomes: The SVR III Study

OBJECTIVE

In the SVR trial (Single Ventricle Reconstruction), newborns with hypoplastic left heart syndrome were randomly assigned to receive a modified Blalock-Taussig-Thomas shunt (mBTTS) or a right ventricle-to-pulmonary artery shunt (RVPAS) at Norwood operation. Transplant-free survival was superior in the RVPAS group at 1 year, but no longer differed by treatment group at 6 years; both treatment groups had accumulated important morbidities. In the third follow-up of this cohort (SVRIII [Long-Term Outcomes of Children With Hypoplastic Left Heart Syndrome and the Impact of Norwood Shunt Type]), we measured longitudinal outcomes and their risk factors through 12 years of age.

METHODS

Annual medical history was collected through record review and telephone interviews. Cardiac magnetic resonance imaging (CMR), echocardiogram, and cycle ergometry cardiopulmonary exercise tests were performed at 10 through 14 years of age among participants with Fontan physiology. Differences in transplant-free survival and complication rates (eg, arrhythmias or protein-losing enteropathy) were identified through 12 years of age. The primary study outcome was right ventricular ejection fraction (RVEF) by CMR, and primary analyses were according to shunt type received. Multivariable linear and Cox regression models were created for RVEF by CMR and post-Fontan transplant-free survival.

RESULTS

Among 549 participants enrolled in SVR, 237 of 313 (76%; 60.7% male) transplant-free survivors (mBTTS, 105 of 147; RVPAS, 129 of 161; both, 3 of 5) participated in SVRIII. RVEF by CMR was similar in the shunt groups (RVPAS, 51±9.6 [n=90], and mBTTS, 52±7.4 [n=75]; P=0.43). The RVPAS and mBTTS groups did not differ in transplant-free survival by 12 years of age (163 of 277 [59%] versus 144 of 267 [54%], respectively; P=0.11), percentage predicted peak Vo2 for age and sex (74±18% [n=91] versus 72±18% [n=84]; P=0.71), or percentage predicted work rate for size and sex (65±20% versus 64±19%; P=0.65). The RVPAS versus mBTTS group had a higher cumulative incidence of protein-losing enteropathy (5% versus 2%; P=0.04) and of catheter interventions (14 versus 10 per 100 patient-years; P=0.01), but had similar rates of other complications.

CONCLUSIONS

By 12 years after the Norwood operation, shunt type has minimal association with RVEF, peak Vo2, complication rates, and transplant-free survival. RVEF is preserved among the subgroup of survivors who underwent CMR assessment. Low transplant-free survival, poor exercise performance, and accruing morbidities highlight the need for innovative strategies to improve long-term outcomes in patients with hypoplastic left heart syndrome.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT0245531.

Outcomes After Hybrid Palliation for Infants With Critical Left Heart Obstruction

BACKGROUND

Hybrid palliation (bilateral pulmonary artery banding with or without ductal stenting) is an initial management strategy for infants with critical left heart obstruction and serves as palliation until subsequent operations are pursued.

OBJECTIVES

This study sought to determine patient characteristics and factors associated with subsequent outcomes for infants who underwent hybrid palliation.

METHODS

From 2005 to 2019, 214 of 1,236 prospectively enrolled infants within the Congenital Heart Surgeons' Society's critical left heart obstruction cohort underwent hybrid palliation across 24 institutions. Multivariable hazard modeling with competing risk methodology was performed to determine risk and factors associated with outcomes of biventricular repair, Fontan procedure, transplantation, or death.

RESULTS

Preoperative comorbidities (eg, prematurity, low birth weight, genetic syndrome) were identified in 70% of infants (150 of 214). Median follow-up was 7 years, ranging up to 17 years. Overall 12-year survival was 55%. At 5 years after hybrid palliation, 9% had biventricular repair, 36% had Fontan procedure, 12% had transplantation, 35% died without surgical endpoints, and 8% were alive without an endpoint. Factors associated with transplantation were absence of ductal stent, older age, absent interatrial communication, smaller aortic root size, larger tricuspid valve area z-score, and larger left ventricular volume. Factors associated with death were low birth weight, concomitant genetic syndrome, cardiopulmonary bypass use during hybrid palliation, moderate to severe tricuspid valve regurgitation, and smaller ascending aortic size.

CONCLUSIONS

Mortality remains high after hybrid palliation for infants with critical left heart obstruction. Nonetheless, hybrid palliation may facilitate biventricular repair for some infants and for others may serve as stabilization for intended functional univentricular palliation or primary transplantation.

Genetic and clinical variables act synergistically to impact neurodevelopmental outcomes in children with single ventricle heart disease

BACKGROUND

Recent large-scale sequencing efforts have shed light on the genetic contribution to the etiology of congenital heart defects (CHD); however, the relative impact of genetics on clinical outcomes remains less understood. Outcomes analyses using genetics are complicated by the intrinsic severity of the CHD lesion and interactions with conditionally dependent clinical variables.

METHODS

Bayesian Networks were applied to describe the intertwined relationships between clinical variables, demography, and genetics in a cohort of children with single ventricle CHD.

RESULTS

As isolated variables, a damaging genetic variant in a gene related to abnormal heart morphology and prolonged ventilator support following stage I palliative surgery increase the probability of having a low Mental Developmental Index (MDI) score at 14 months of age by 1.9- and 5.8-fold, respectively. However, in combination, these variables act synergistically to further increase the probability of a low MDI score by 10-fold. The absence of a damaging variant in a known syndromic CHD gene and a shorter post-operative ventilator support increase the probability of a normal MDI score 1.7- and 2.4-fold, respectively, but in combination increase the probability of a good outcome by 59-fold.

CONCLUSIONS

Our analyses suggest a modest genetic contribution to neurodevelopmental outcomes as isolated variables, similar to known clinical predictors. By contrast, genetic, demographic, and clinical variables interact synergistically to markedly impact clinical outcomes. These findings underscore the importance of capturing and quantifying the impact of damaging genomic variants in the context of multiple, conditionally dependent variables, such as pre- and post-operative factors, and demography.

Transcatheter Ductal Stents Versus Surgical Systemic-Pulmonary Artery Shunts in Neonates With Congenital Heart Disease With Ductal-Dependent Pulmonary Blood Flow: Trends and Associated Outcomes From the Pediatric Health Information System Database

Background Surgical systemic-to-pulmonary artery shunts have been the standard approach to establish stable pulmonary blood flow in neonates with congenital heart disease with ductal-dependent pulmonary blood flow. More recently, transcatheter ductal stents have been performed as an alternative, less invasive intervention. We aimed to characterize trends in the utilization of surgical shunts versus ductal stents and compare associated outcomes. Methods and Results Using data from the Pediatric Health Information System, we retrospectively analyzed neonates with congenital heart disease with ductal-dependent pulmonary blood flow who underwent surgical shunt or ductal stent placement between January 2016 and December 2021. Patients were identified by International Classification of Diseases, Tenth Revision (ICD-10) diagnosis and procedure codes. The primary outcome was length of hospital stay. Secondary outcomes were reintervention risk and adjusted hospital costs. Of 936 patients included, 65.2% underwent a surgical shunt over the 6-year period. The proportion who underwent ductal stenting increased from 19% to 53.4% from 2016 to 2021. The median adjusted difference in postintervention length of hospital stay was 11 days greater for the surgical shunt cohort (95% CI, 7.2-14.8; P<0.001). The adjusted reintervention risks within 3 (odds ratio [OR], 3.37 [95% CI, 1.91-5.95], P<0.001) and 6 months (OR, 2.43 [95% CI, 1.62-3.64], P<0.001) were significantly greater in the ductal stent group. Median adjusted index hospital costs were $198 300 ($11 6400-$340 000) versus $120 400 ($81 800-$192 400) for the surgical shunt and ductal stent cohorts, respectively (P<0.001). Conclusions Ductal stenting has become an increasingly utilized palliative approach to secure pulmonary blood flow in neonates with congenital heart disease with ductal-dependent pulmonary blood flow in the United States. Ductal stenting is associated with decreased length of hospital stay and reduced overall cost for the index hospitalization but with a greater reintervention risk than surgical shunting.

Automated prediction of cardiorespiratory deterioration in patients with single-ventricle parallel circulation: A multicenter validation study

Objectives

Patients with single-ventricle physiology have a significant risk of cardiorespiratory deterioration between their first- and second-stage palliation surgeries. Detection of deterioration episodes may allow for early intervention and improved outcomes.

Methods

A prospective study was executed at Nationwide Children's Hospital, Children's Hospital of Philadelphia, and Children's Hospital Colorado to collect physiologic data of subjects with single ventricle physiology during all hospitalizations between neonatal palliation and II surgeries using the Sickbay software platform (Medical Informatics Corp). Timing of cardiorespiratory deterioration events was captured via chart review. The predictive algorithm previously developed and validated at Texas Children's Hospital was applied to these data without retraining. Standard metrics such as receiver operating curve area, positive and negative likelihood ratio, and alert rates were calculated to establish clinical performance of the predictive algorithm.

Results

Our cohort consisted of 58 subjects admitted to the cardiac intensive care unit and stepdown units of participating centers over 14 months. Approximately 28,991 hours of high-resolution physiologic waveform and vital sign data were collected using the Sickbay. A total of 30 cardiorespiratory deterioration events were observed. the risk index metric generated by our algorithm was found to be both sensitive and specific for detecting impending events one to two hours in advance of overt extremis (receiver operating curve = 0.927).

Conclusions

Our algorithm can provide a 1- to 2-hour advanced warning for 53.6% of all cardiorespiratory deterioration events in children with single ventricle physiology during their initial postop course as well as interstage hospitalizations after stage I palliation with only 2.5 alarms being generated per patient per day.

Norwood operation versus comprehensive stage II after bilateral pulmonary artery banding palliation for infants with critical left heart obstruction

OBJECTIVE

To determine patient characteristics and outcomes after Norwood versus comprehensive stage II (COMPSII) for infants with critical left heart obstruction who had prior hybrid palliation (bilateral pulmonary artery banding ± ductal stent).

METHODS

From 23 Congenital Heart Surgeons' Society institutions (2005-2020), 138 infants underwent hybrid palliation followed by either Norwood (n = 73, 53%) or COMPSII (n = 65). Baseline characteristics were compared between Norwood and COMPSII groups. Parametric hazard model with competing risk methodology was used to determine risk and factors associated with outcomes of Fontan, transplantation, or death.

RESULTS

Infants who underwent Norwood versus COMPSII had a higher prevalence of prematurity (26% vs 14%, P = .08), lower birth weight (median 2.8 vs 3.2 kg, P < .01) and less frequent ductal stenting (37% vs 99%; P < .01). Norwood was performed at a median age of 44 days and median weight of 3.5 kg, versus COMPSII at 162 days and 6.0 kg (both P < .01). Median follow-up was 6.5 years. At 5 years after Norwood and COMPSII, respectively; 50% versus 68% had Fontan (P = .16), 3% versus 5% had transplantation (P = .70), 40% versus 15% died (P = .10), and 7% versus 11% are alive without transition, respectively. For factors associated with either mortality or Fontan, only preoperative mechanical ventilation occurred more frequently in the Norwood group.

CONCLUSIONS

Higher prevalence of prematurity, lower birth weight, and other patient-related characteristics in the Norwood versus COMPSII groups may influence differences in outcomes that were not statistically significant for this limited risk-adjusted cohort. The clinical decision regarding Norwood versus COMPSII after initial hybrid palliation remains challenging.

New approach in stage 1 surgery for hypoplastic left heart syndrome: preliminary outcomes

OBJECTIVES

We present the short-term results of an alternative method in stage 1 surgery for hypoplastic left heart syndrome.

METHODS

Data of 16 consecutive patients who were treated with the novel method in our clinic between February 2019 and March 2021 were analysed retrospectively. Preoperative data and postoperative follow-up were recorded.

RESULTS

Of the 16 operated patients, 12 were diagnosed with hypoplastic left heart syndrome, while four were diagnosed with hypoplastic left heart syndrome variants. Seven patients died during early postoperative period. One patient died at home waiting stage 2 surgery. Three patient underwent stage 2 surgery. Pulmonary artery reconstruction was performed in one patient due to left pulmonary artery distortion.

CONCLUSIONS

We believe that our method can be an effective alternative in the surgery of hypoplastic left heart syndrome and its variants. It is hoped that with increasing number of studies and more experience better outcome will be achieved.

Textbook outcome for the Norwood operation-an informative quality metric in congenital heart surgery

Objectives

To develop a more holistic measure of center performance than operative mortality, we created a composite "textbook outcome" for the Norwood operation using several postoperative end points. We hypothesized that achieving the textbook outcome would have a positive prognostic and financial impact.

Methods

This was a single-center retrospective study of primary Norwood operations from 2005 to 2021. Through interdisciplinary clinician consensus, textbook outcome was defined as freedom from operative mortality, open or catheter-based reintervention, 30-day readmission, extracorporeal membrane oxygenation, cardiac arrest, reintubation, length of stay >75%ile from Society of Thoracic Surgeons data report (66 days), and mechanical ventilation duration >75%ile (10 days). Multivariable logistic regression and Cox proportional hazards modeling were used to determine predictive factors for textbook outcome achievement and association of the outcome with long-term survival, respectively.

Results

Overall, 30% (58/196) of patients met the textbook outcome. Common reasons for failure to attain textbook outcome were prolonged ventilation (68/138, 49%) and reintubation (63/138, 46%). In multivariable analysis, greater weight (odds ratio [OR], 2.11; 95% confidence interval [CI], 1.17-3.95; P = .02) was associated with achieving the textbook outcome whereas preoperative shock (OR, 0.36; 95% CI, 0.13-0.87; P = .03) and longer bypass time (OR, 0.99; 95% CI, 0.98-1.00; P = .002) were negatively associated. Patients who met the outcome incurred fewer hospital costs ($152,430 [141,798-177,983] vs $269,070 [212,451-372,693], P < .001), and after adjusting for patient factors, achieving textbook outcome was independently associated with decreased risk of all-cause mortality (hazard ratio, 0.45; 95% CI, 0.22-0.89; P = .02).

Conclusions

Outcomes continue to improve within congenital heart surgery, making operative mortality a less-sensitive metric. The Norwood textbook outcome may represent a balanced measure of a successful episode of care.

Risk of in-hospital Deterioration for Children with Single Ventricle Physiology

Children with single ventricle physiology (SV) are at high risk of in-hospital morbidity and mortality. Identifying children at risk for deterioration may allow for earlier escalation of care and subsequently decreased mortality.We conducted a retrospective chart review of all admissions to the pediatric cardiology non-ICU service from 2014 to 2018 for children < 18 years old. We defined clinical deterioration as unplanned transfer to the ICU or inpatient mortality. We selected children with SV by diagnosis codes and defined infants as children < 1 year old. We compared demographic, vital sign, and lab values between infants with and without a deterioration event. We evaluated vital sign and medical therapy changes before deterioration events.Among infants with SV (129 deterioration events over 225 admissions, overall 25% with hypoplastic left heart syndrome), those who deteriorated were younger (p = 0.001), had lower baseline oxygen saturation (p = 0.022), and higher baseline respiratory rate (p = 0.022), heart rate (p = 0.023), and hematocrit (p = 0.008). Median Duke Pediatric Early Warning Score increased prior to deterioration (p < 0.001). Deterioration was associated with administration of additional oxygen support (p = 0.012), a fluid bolus (p < 0.001), antibiotics (p < 0.001), vasopressor support (p = 0.009), and red blood cell transfusion (p < 0.001).Infants with SV are at high risk for deterioration. Integrating baseline and dynamic patient data from the electronic health record to identify the highest risk patients may allow for earlier detection and intervention to prevent clinical deterioration.

A dynamic Norwood mortality estimation: Characterizing individual, updated, predicted mortality trajectories after the Norwood operation

Objective

Post-Norwood mortality remains high and unpredictable. Current models for mortality do not incorporate interstage events. We sought to determine the association of time-related interstage events, along with (pre)operative characteristics, with death post-Norwood and subsequently predict individual mortality.

Methods

From the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort, 360 neonates underwent Norwood operations from 2005 to 2016. Risk of death post-Norwood was modeled using a novel application of parametric hazard analysis, in which baseline and operative characteristics and time-related adverse events, procedures, and repeated weight and arterial oxygen saturation measurements were considered. Individual predicted mortality trajectories that dynamically update (increase or decrease) over time were derived and plotted.

Results

After the Norwood, 282 patients (78%) progressed to stage 2 palliation, 60 patients (17%) died, 5 patients (1%) underwent heart transplantation, and 13 patients (4%) were alive without transitioning to another end point. In total, 3052 postoperative events occurred and 963 measures of weight and oxygen saturation were obtained. Risk factors for death included resuscitated cardiac arrest, moderate or greater atrioventricular valve regurgitation, intracranial hemorrhage/stroke, sepsis, lower longitudinal oxygen saturation, readmission, smaller baseline aortic diameter, smaller baseline mitral valve z-score, and lower longitudinal weight. Each patient's predicted mortality trajectory varied as risk factors occurred over time. Groups with qualitatively similar mortality trajectories were noted.

Conclusions

Risk of death post-Norwood is dynamic and most frequently associated with time-related postoperative events and measures, rather than baseline characteristics. Dynamic predicted mortality trajectories for individuals and their visualization represent a paradigm shift from population-derived insights to precision medicine at the patient level.

Age at surgery and outcomes following neonatal cardiac surgery: An analysis from the Pediatric Cardiac Critical Care Consortium

OBJECTIVE

The optimal timing for neonatal cardiac surgery is a potentially modifiable factor that may affect outcomes. We studied the relationship between age at surgery (AAS) and outcomes across multiple hospitals, focusing on neonatal operations where timing appears is not emergency.

METHODS

We studied neonates ≥37 weeks' gestation and ≥2.5 kg admitted to a treating hospital on or before day of life 2 undergoing selected index cardiac operations. The impact of AAS on outcomes was evaluated across the entire cohort and a standard risk subgroup (ie, free of preoperative mechanical ventilation, mechanical circulatory support, or other organ failure). Outcomes included mortality, major morbidity (ie, cardiac arrest, mechanical circulatory support, unplanned cardiac reintervention, or neurologic complication), and postoperative cardiac intensive care unit and hospital length of stay. Post hoc analyses focused on operations undertaken between day of life 2 and 7.

RESULTS

We studied 2536 neonates from 47 hospitals. AAS from day of life 2 through 7 was not associated with risk adjusted mortality or major morbidity among the entire cohort and the standard risk subgroup. Older AAS, although associated with modest increases in postoperative cardiac intensive care unit and hospital length of stay in the entire cohort, was not associated with hospital length of stay in the standard risk subgroup.

CONCLUSIONS

Among select nonemergency neonatal cardiac operations, AAS between day of life 2 and 7 was not found to be associated with risk adjusted mortality or major morbidity. Although delays in surgical timing may modestly increase preoperative resource use, studies of AAS and outcomes not evident at the time of discharge are needed.

Impact of Reintervention During Stage 1 Palliation Hospitalization: A National, Multicenter Study

BACKGROUND

Stage 1 palliation (S1P) for hypoplastic left heart syndrome remains associated with high morbidity and mortality. Previous studies on burden of reinterventions did not include patients who remain hospitalized before stage 2 palliation (S2P). This study described the rate of reintervention during S1P hospitalization and sought to determine the impact of reintervention on outcomes.

METHODS

All participants enrolled in phase II of the National Pediatric Cardiology Quality Improvement Collaborative after S1P were included in this study. The primary outcome was the rate of reintervention during hospitalization after S1P and before hospital discharge or S2P. Reintervention was defined as 1 or more unplanned interventional cardiac catheterizations or surgical reoperations.

RESULTS

Between March 1, 2016 and October 1, 2019, 1367 participants underwent S1P and 339 (24.8%) had a reintervention; most commonly to address the source of pulmonary blood flow. Gestational age, weight at S1P, atrioventricular septal defect, heterotaxy, preoperative pulmonary artery bands, hybrid S1P, and an additional bypass run or early extracorporeal membrane oxygenation were significantly associated with reintervention. Participants in the reintervention group experienced higher rates of nearly all postoperative complications, were less likely to be discharged before S2P (57.1% vs 86%; P < .001), and more likely to experience in-hospital mortality (17% vs 5%; P < .001).

CONCLUSIONS

Unplanned reintervention during hospitalization after S1P palliation occurred in 25% of participants in a large, registry-based national cohort. Participants who underwent reintervention were more likely to remain as inpatient and were less likely to survive to S2P. Reintervention was associated with a multitude of postoperative complications that affect survival and long-term outcome.

Norwood Operation: Immediate vs Delayed Sternal Closure

BACKGROUND

The Norwood operation is a complex neonatal surgery. There are limited data to inform the timing of sternal closure. After the Norwood operation, delayed sternal closure (DSC) is frequent. We aimed to examine the association of DSC with outcomes, with a particular interest in how sternal closure at the time of surgery compared with the timing of DSC. Our outcomes included mortality, length of ventilation, length of stay, and postoperative complications.

METHODS

This retrospective study included neonates who underwent a Norwood operation reported in the Pediatric Cardiac Critical Care Consortium registry from February 2019 through April 2021. Outcomes of patients with closed sternum were compared to those with sternal closure prior to postoperative day 3 (early closure) and prior to postoperative day 6 (intermediate closure).

RESULTS

The incidence of DSC was 74% (500 of 674). The median duration of open sternum was 4 days (interquartile range 3-5 days). Comparing patients with closed sternum to patients with early sternal closure, there was no statistical difference in mortality rate (1.1% vs 0%) and the median hospital postoperative stay (30 days vs 31 days). Compared with closed sternum, patients with intermediate sternal closure required longer mechanical ventilation (5.9 days vs 3.9 days) and fewer subsequent sternotomies (3% vs 7.5%).

CONCLUSIONS

For important outcomes following the Norwood operation there is no advantage to chest closure at the time of surgery if the chest can be closed prior to postoperative day 3.

Contemporary Outcomes of Tracheostomy in Patients With Single Ventricle Heart Lesions

OBJECTIVES

Approximately 0.2% to 2.7% of children with congenital heart disease require a tracheostomy after cardiac surgery with the majority having single ventricle (SV) type heart lesions. Tracheostomy in SV patients is reported to be associated with high mortality. We hypothesized that short- and long-term survival of patients with SV heart disease would vary according to tracheostomy indication.

METHODS

This is a single center, 20-year, retrospective review of all patients with SV heart disease who underwent tracheostomy. Demographic, cardiac anatomy, surgical, intensive care unit, and hospital course data were collected. The primary outcome was survival following tracheostomy. Secondary outcome was the completion of staged palliation to Fontan.

RESULTS

In total, 25 patients with SV heart disease who underwent tracheostomy were included. Indications for tracheostomy included one or more of the following: tracheobronchomalacia (n = 8), vocal cord paralysis (n = 7), tracheal/subglottic stenosis (n = 6), primary respiratory insufficiency (n = 4), diaphragm paralysis (n = 3), suboptimal hemodynamics (n = 2), and other upper airway issues (n = 1). Survival at six months, one year, five years, and ten years was 76%, 68%, 63%, and 49%, respectively. Most patients completed Fontan palliation (64%). Patients who underwent tracheostomy for suboptimal hemodynamics and/or respiratory insufficiency had a higher mortality risk compared to those with indications of upper airway obstruction or diaphragm paralysis (hazard ratio 4.1, 95% confidence interval 1.2-13.7; P = .02).

CONCLUSIONS

Mortality risk varies according to tracheostomy indication in patients with SV heart disease. Tracheostomy may allow staged surgical palliation to proceed with acceptable risk if it was indicated for anatomic or functional airway dysfunction.

The Prevalence of Congenital Anomalies of the Airway or Lung in Infants with Hypoplastic Left Heart Syndrome and Differences in Midterm Outcomes: A National Pediatric Cardiology Quality Improvement Collaborative Registry Analysis

Infants with single ventricle physiology and congenital anomalies of the airway and/or lung are potentially poor candidates for staged palliation. The prevalence and midterm outcomes for patients with anomalies of the airway or lung with hypoplastic left heart syndrome are unknown. We performed an analysis of data in infants with hypoplastic left heart syndrome from the National Pediatric Cardiology Quality Improvement Collaborative registry. The prevalence of congenital anomalies of the airway or lung in the registry was determined. Clinical characteristics and midterm outcomes were compared between infants with hypoplastic left heart syndrome with and without anomalies of the airway or lung. Fifty-seven (2.3%) of 2467 infants with hypoplastic left heart syndrome enrolled in the registry had congenital airway or lung anomalies. Infants congenital anomalies of the airway or lung had significantly lower transplant-free survival at 1 year (49.5 vs 77.2%, p < 0.001). Infants with airway or lung anomalies had longer combined hospital length of stay for stage 1 and stage 2 palliation (102 vs 65.1 days, p < 0.001) and underwent more major procedures (2.04 vs 0.93 procedures, p < 0.001) than those without. There was no difference in the number of interstage readmissions (1.85 vs 1.89, p = 0.87) or need for non-oral feeding supplementation (71.4 vs 54.5%, p = 0.12) between groups. Infants enrolled in the National Pediatric Cardiology Quality Improvement Collaborative registry with hypoplastic left heart syndrome and anomalies of the airway or lung have increased morbidity and mortality at 1 year compared to those with hypoplastic left heart syndrome alone.

Cumulative comorbid conditions influence mortality risk after staged palliation for hypoplastic left heart syndrome and variants

OBJECTIVE

Prematurity, low birth weight, genetic syndromes, extracardiac conditions, and secondary cardiac lesions are considered high-risk conditions associated with mortality after stage 1 palliation. We report the impact of these conditions on outcomes from a prospective multicenter improvement collaborative.

METHODS

The National Pediatric Cardiology Quality Improvement Collaborative Phase II registry was queried. Comorbid conditions were categorized and quantified to determine the cumulative burden of high-risk diagnoses on survival to the first birthday. Logistic regression was applied to evaluate factors associated with mortality.

RESULTS

Of the 1421 participants, 40% (575) had at least 1 high-risk condition. The aggregate high-risk group had lower survival to the first birthday compared with standard risk (76.2% vs 88.1%, P < .001). Presence of a single high-risk diagnosis was not associated with reduced survival to the first birthday (odds ratio, 0.71; confidence interval, 0.49-1.02, P = .066). Incremental increases in high-risk diagnoses were associated with reduced survival to first birthday (odds ratio, 0.23; confidence interval, 0.15-0.36, P < .001) for 2 and 0.17 (confidence interval, 0.10-0.30, P < .001) for 3 to 5 high-risk diagnoses. Additional analysis that included prestage 1 palliation characteristics and stage 1 palliation perioperative variables identified multiple high-risk diagnoses, poststage 1 palliation extracorporeal membrane oxygenation support (odds ratio, 0.14; confidence interval, 0.10-0.22, P < .001), and cardiac reoperation (odds ratio, 0.66; confidence interval, 0.45-0.98, P = .037) to be associated with reduced survival odds to the first birthday.

CONCLUSIONS

The presence of 1 high-risk diagnostic category was not associated with decreased survival at 1 year. Cumulative diagnoses across multiple high-risk diagnostic categories were associated with decreased odds of survival. Further patient accrual is needed to evaluate the impact of specific comorbid conditions within the broader high-risk categories.

Increased interstage morbidity and mortality following stage 1 palliation in patients with genetic abnormalities

BACKGROUND

Hypoplastic left heart syndrome and single ventricle variants with aortic hypoplasia are commonly classified as severe forms of CHD. We hypothesised patients with these severe defects and reported genetic abnormalities have increased morbidity and mortality during the interstage period.

METHODS AND RESULTS

This was a retrospective review of the National Pediatric Cardiology Quality Improvement Collaborative Phase I registry. Three patient groups were identified: major syndromes, other genetic abnormalities, and no reported genetic abnormality. Tukey post hoc test was applied for pairwise group comparisons of length of stay, death, and combined outcome of death, not a candidate for stage 2 palliation, and heart transplant. Participating centres received a survey to establish genetic testing and reporting practices. Of the 2182 patients, 110 (5%) had major genetic syndromes, 126 (6%) had other genetic abnormalities, and 1946 (89%) had no genetic abnormality. Those with major genetic syndromes weighed less at birth and stage 1 palliation. Patients with no reported genetic abnormalities reached full oral feeds sooner and discharged earlier. The combined outcome of death, not a candidate for stage 2 palliation, and heart transplant was more common in those with major syndromes. Survey response was low (n = 23, 38%) with only 14 (61%) routinely performing and reporting genetic testing.

CONCLUSIONS

Patients with genetic abnormalities experienced greater morbidity and mortality during the interstage period than those with no reported genetic abnormalities. Genetic testing and reporting practices vary significantly between participating centres.

Development of a Model for the Pediatric Survival After Veno-Arterial Extracorporeal Membrane Oxygenation Score: The Pedi-SAVE Score

Pediatric cardiac extracorporeal membrane oxygenation (ECMO) patients have high mortality rates. The purpose of our study was to develop and validate the Pediatric Survival After Veno-arterial ECMO (Pedi-SAVE) score for predicting survival at hospital discharge after pediatric cardiac veno-arterial (VA) ECMO. We used data for pediatric cardiac VA-ECMO patients from the Extracorporeal Life Support Organization registry (1/1/2001-12/31/2015). Development and validation cohorts were created using 2:1 random sampling. Predictors of survival to develop pre- and postcannulation models were selected using multivariable logistic regression and random forest models. ß-coefficients were standardized to create the Pedi-SAVE score. Of 10,091 pediatric cardiac VA-ECMO patients, 4,996 (50%) survived to hospital discharge. Pre- and postcannulation Pedi-SAVE scores predicted that the lowest risk patients have a 65% and 74% chance of survival at hospital discharge, respectively, compared to 33% and 22% in the highest risk patients. In the validation cohort, pre- and postcannulation Pedi-SAVE scores had c-statistics of 0.64 and 0.71, respectively. Precannulation factors associated with survival included: nonsingle ventricle congenital heart disease, older age, white race, lower STAT mortality category, higher pH, not requiring acid-buffer administration, <2 cardiac procedures, and indication for VA-ECMO other than failure to wean from cardiopulmonary bypass. Postcannulation, additional factors associated with survival included: lower ECMO pump flows at 24 hours and lack of complications. The Pedi-SAVE score is a novel validated tool to predict survival at hospital discharge for pediatric cardiac VA-ECMO patients, and is an important advancement in risk adjustment and benchmarking for this population.

Preoperative in-hospital mortality in neonates with critical CHD

OBJECTIVE

Data regarding preoperative mortality in neonates with critical CHD are sparse and would aid patient care and family counselling. The objective of this study was to utilise a multicentre administrative dataset to report the rate of and identify risk factors for preoperative in-hospital mortality in neonates with critical CHD across US centres.

STUDY DESIGN

The Pediatric Health Information System database was utilised to search for newborns ≤30 days old, born 1 January 2009 to 30 June 2018, with an ICD-9/10 code for d-transposition of the great arteries, truncus arteriosus, interrupted aortic arch, or hypoplastic left heart syndrome. Preoperative in-hospital mortality was defined as patients who died prior to discharge without an ICD code for cardiac surgery or interventional catheterisation.

RESULTS

Overall preoperative mortality rate was at least 5.4% (690/12,739) and varied across diagnoses (d-TGA 2.9%, TA 8.3%, IAA 5.5%, and HLHS 7.3%) and centres (0-20.5%). In multivariable analysis, risk factors associated with preoperative mortality included preterm delivery (<37 weeks) (OR 2.3, 95% CI: 1.8-2.9; p < 0.01), low birth weight (<2.5 kg) (OR 3.8, 95% CI: 3.0-4.7; p < 0.01), and genetic abnormality (OR 1.6, 95% CI: 1.2-2.2; p < 0.01). Centre average surgical volume was not a significant risk factor.

CONCLUSION

Approximately 1 in 20 neonates with critical CHD suffered preoperative in-hospital mortality, and rates varied across diagnoses and centres. Better understanding of the factors that drive the variation (e.g. patient factors, preoperative care models, surgical timing) could help identify patient care improvement opportunities and inform conversations with families.

Nutritional Considerations for the Neonate With Congenital Heart Disease

The importance of nutrition in managing critically ill infants with congenital heart disease (CHD) is foundational to optimizing short- and long-term health outcomes. Growth failure and malnutrition are common in infants with CHD. The etiology of growth failure in this population is often multifactorial and may be related to altered metabolic demands, compromised blood flow to the intestine leading to nutrient malabsorption, cellular hypoxia, inadequate energy intake, and poor oral-motor skills. A dearth of high-quality studies and gaps in previously published guidelines have led to wide variability in nutrition practices that are locally driven. This review provides recommendations from the nutrition subgroup of the Neonatal Cardiac Care Collaborative for best evidence-based practices in the provision of nutritional support in infants with CHD. The review of evidence and recommendations focused on 6 predefined areas of clinical care for a target population of infants &lt;6 months with CHD admitted to the ICU or inpatient ward. These areas include energy needs, nutrient requirements, enteral nutrition, feeding practice, parenteral nutrition, and outcomes. Future progress will be directed at quality improvement efforts to optimize perioperative nutrition management with an increasing emphasis on individualized care based on nutritional status, cardiorespiratory physiology, state of illness, and other vulnerabilities.

High-Risk Anatomic Subsets in Hypoplastic Left Heart Syndrome

Despite overall improvements in outcomes for patients with hypoplastic left heart syndrome, there remain anatomic features that can place these patients at higher risk throughout their treatment course. These include severe preoperative obstruction to pulmonary venous return, restrictive atrial septum, coronary fistulae, severe tricuspid regurgitation, smaller ascending aorta diameter (especially if <2 mm), and poor ventricular function. The risk of traditional staged palliation has led to the development of alternative strategies for such patients. To further improve the outcomes, we must continue to diligently examine and study anatomic details in HLHS patients.

Impact of Intraoperative Residual Lesions and Timing of Extracorporeal Membrane Oxygenation on Outcomes Following First-Stage Palliation of Single Ventricle Heart Disease

BACKGROUND

Data regarding the influence of intraoperative residual lesions on extracorporeal membrane oxygenation (ECMO) following the Norwood procedure are limited. Moreover, the significance of postoperative ECMO timing on in-hospital outcomes remains incompletely characterized.

METHODS

This was a single-center, retrospective review of consecutive patients who underwent the Norwood operation from January 1997 to November 2017. Patients with at least minor residual lesions based on the intraoperative postcardiopulmonary bypass echocardiogram were identified. The association between residual lesions and postoperative ECMO was assessed with logistic regression, adjusting for age, weight, prematurity, various preoperative system-specific and procedural risk factors, shunt type, and era. Among patients receiving ECMO, associations between late ECMO (≥3 days post-Norwood) and in-hospital mortality or transplant, postoperative hospital length-of-stay, and cost of hospitalization were evaluated using logistic regression or generalized linear models with a gamma distribution and logarithmic link.

RESULTS

Among 500 patients, 78 (15.6%) received ECMO postoperatively. On multivariable analysis, the presence of at least minor residual lesions (odds ratio, 4.4; 95% CI, 2.1-9.3; P < .001) was associated with postoperative ECMO. In the ECMO subpopulation, there were 44 (56.4%) deaths or transplants. Late ECMO was associated with increased risk of in-hospital mortality or transplant (adjusted odds ratio, 6.2; 95% CI, 1.5-26.0), longer postoperative hospital length of stay (regression coefficient, 0.7; 95% CI, 0.3-1.1), and greater cost (regression coefficient, 0.6; 95%, CI 0.4-0.7), versus early ECMO (all P values < .05).

CONCLUSIONS

The presence of even minor intraoperative residua significantly increases the risk of ECMO following the Norwood operation. Among patients receiving ECMO postoperatively, early institution of ECMO is associated with lower mortality and resource utilization.

Factors Associated with Inability to Discharge After Stage 1 Palliation for Single Ventricle Heart Disease: An Analysis of the National Pediatric Cardiology Quality Improvement Collaborative Database

Patient-level characteristics associated with survival for single ventricle heart disease following initial staged palliation have been described. However, the impact of peri-operative events on hospital discharge has not been examined. To characterize patient-level characteristics and peri-operative events that were associated with inability to be discharged after Stage 1 palliation (S1P). Analysis of the National Pediatric Cardiology Quality Improvement Collaborative Dataset including patients who underwent a S1P procedure between 2016 and 2019 (Norwood or Hybrid Stage 1 procedure). We examined patient-level characteristics and peri-operative events as possible predictors of inability to discharge after S1P. We constructed multivariate logistic regression models examining post-S1P discharge and in-hospital mortality, adjusting for covariates. 843 patients underwent a S1P and 717 (85%) patients were discharged home or remained inpatient until Stage 2 for social but not medical concerns. Moderate or greater pre-operative atrioventricular valve regurgitation (odds ratio (OR) 4.6, 95% confidence interval (CI) 1.8-12), presence of high-risk pre-operative adverse events (OR 1.5, 95%CI 1.0-2.3), peri-operative events: temporary dialysis (OR 5.4, 95%CI 1.5-18.9), cardiac catheterization or cardiac surgery (OR 2.9, 95%CI 1.8-4.6), sepsis (OR 2.7, 95%CI 1.2-6.2), junctional tachycardia (OR 2.6, 95%CI 1.0-6.3), necrotizing enterocolitis (OR 2.6, 95%CI 1.3-5.2), ECMO (OR 2.5, 95%CI 1.4-4.3), neurological injury (OR 2.1, 95%CI 1.1-4.1), and re-intubation (OR 1.8, 95%CI 1.1-2.9) were associated with inability to discharge after Stage 1. Cardiac anatomical factors, pre-operative adverse events, post-operative re-intubation, post-operative ECMO, infectious complications, and unplanned catheter or surgical re-interventions were associated with inability to discharge after S1P. These findings suggest that quality improvement efforts aimed at reducing these peri-operative events may improve Stage 1 survival and likelihood of discharge.

Association Between Digoxin Use and Cardiac Function in Infants With Single-Ventricle Congenital Heart Disease During the Interstage Period

OBJECTIVES

To examine the association between digoxin use and cardiac function assessed by echocardiographic indices in infants with single-ventricle (SV) congenital heart disease (CHD) during the interstage period.

DESIGN

Retrospective cohort study.

SETTING

Fifteen North American hospitals.

PATIENTS

Infants discharged home following stage 1 palliation (S1P) and prior to stage 2 palliation (S2P). Infants with no post-S1P and pre-S2P echocardiograms were excluded.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 373 eligible infants who met inclusion criteria, 140 (37.5%) were discharged home on digoxin. In multivariable linear and logistic regressions, we found that compared with infants discharged home without digoxin, those discharged with digoxin had a smaller increase in end-systolic volume (β = -8.17 [95% CI, -15.59 to -0.74]; p = 0.03) and area (β = -1.27 [-2.45 to -0.09]; p = 0.04), as well as a smaller decrease in ejection fraction (β = 3.38 [0.47-6.29]; p = 0.02) and fractional area change (β = 2.27 [0.14-4.41]; p = 0.04) during the interstage period.

CONCLUSIONS

Digoxin may partially mitigate the expected decrease in cardiac function during the interstage period through its positive inotropic effects. Prospective clinical trials are needed to establish the pharmacokinetics, safety, and efficacy of digoxin use in SV CHD.

Clinical and haemodynamic variables associated with intensive care unit length of stay and early adverse outcomes after the Norwood procedure

OBJECTIVES

This study was performed to determine the clinical and haemodynamic variables associated with early adverse outcomes after the neonatal Norwood procedure.

METHODS

Patients who underwent the neonatal Norwood procedure between 2001 and 2019 were included. The patient diagnosis, morphological characteristics and haemodynamic parameters were analysed to identify factors associated with length of stay (LOS) in the intensive care unit (ICU) and mortality during the stay.

RESULTS

A total of 322 patients were depicted. The median age and weight at the Norwood procedure were 9 days and 3.2 kg, respectively. Certain morphological and preoperative parameters, such as birth weight below 2.5 kg, restrictive atrial septal defect, extracardiac anomalies and the diameter of the ascending aorta, were found to be associated with the LOS in the ICU. Analysis using early postoperative haemodynamic variables revealed that systolic arterial pressure, diastolic arterial pressure, serum lactate levels and reduced ventricular function at 2 days postoperatively were associated with the LOS in the ICU. Birth weight <2.5 kg (P = 0.010), a restrictive atrial septal defect (P = 0.001) and smaller ascending aorta (P = 0.039) were associated with death in the ICU. Reduced ventricular function, lower systolic aortic pressure and higher lactate levels at various time points (P < 0.05) were also associated with ICU deaths. The LOS in the ICU was significantly associated with late mortality (P < 0.001, Hazard Ratio (HR) = 1.015).

CONCLUSIONS

The LOS in the ICU after the Norwood procedure was predicted by early postoperative haemodynamic variables, suggesting that good early postoperative haemodynamics determine early recovery. A prolonged stay in the ICU after the Norwood procedure was associated with late mortality.

Aspirin resistance in infants with shunt-dependent congenital heart disease

INTRODUCTION

Patients with cyanotic heart disease are at an increased risk of developing thrombosis. Aspirin has been the mainstay of prophylactic anticoagulation for shunt-dependent patients with several reports of prevalent aspirin resistance, especially in neonates. We investigate the incidence of aspirin resistance and its relationship to thrombotic events and mortality in a cohort of infants with shunt-dependent physiology.

METHODS

Aspirin resistance was assessed using the VerifyNow™ test on infants with single-ventricle physiology following shunt-dependent palliation operations. In-hospital thrombotic events and mortality data were collected. Statistical analysis was performed to evaluate the effect of aspirin resistance on in-hospital thrombotic events and mortality risk.

RESULTS

Forty-nine patients were included with 41 of these patients being neonates. Six patients (12%) were aspirin resistant. A birth weight < 2500 grams was a significant factor associated with aspirin resistance (p = 0.04). Following a dose increase or additional dose administration, all patients with initial aspirin resistance had a normal aspirin response. There was no statistically significant difference between aspirin resistance and non-resistance groups with respect to thrombotic events. However, a statistically significant incidence of in-hospital mortality in the presence of thrombotic events was observed amongst aspirin-resistant patients (p = 0.04) in this study.

CONCLUSION

Low birth weight was associated with a higher incidence of aspirin resistance. Inadequate initial dosing appears to be the primary reason for aspirin resistance. The presence of both thrombotic events and aspirin resistance was associated with significantly higher in-hospital mortality indicating that these patients warrant closer monitoring.

Distance from home to birth hospital, transfer, and mortality in neonates with hypoplastic left heart syndrome in California

BACKGROUND

Prior studies report a lower risk of mortality among neonates with hypoplastic left heart syndrome (HLHS) who are born at a cardiac surgical center, but many neonates with HLHS are born elsewhere and transferred for repair. We investigated the associations between the distance from maternal home to birth hospital, the need for transfer after birth, sociodemographic factors, and mortality in infants with HLHS in California from 2006 to 2011.

METHODS

We used linked data from two statewide databases to identify neonates for this study. Three groups were included in the analysis: "lived close/not transferred," "lived close/transferred," and "lived far/not transferred." We defined "lived close" versus "lived far" as 11 miles, the median distance from maternal residence to birth hospital. Log-binomial regression models were used to identify the association between sociodemographic variables, distance to birth hospital and transfer. Cox proportional hazards models were used to identify the association between mortality and distance to birth hospital and transfer. Models were adjusted for sociodemographic variables.

RESULTS

Infants in the lived close/not transferred and the lived close/transferred groups (vs. the lived far/not transferred group) were more likely to live in census tracts above the 75th percentile for poverty with relative risks 1.94 (95% confidence interval [CI] 1.41-2.68) and 1.21 (95% CI 1.05-1.40), respectively. Neonatal mortality was higher among the lived close/not transferred group compared with the lived far/not transferred group (hazard ratio 1.77, 95% CI 1.17-2.67).

CONCLUSIONS

Infants born to mothers experiencing poverty were more likely to be born close to home. Infants with HLHS who were born close to home and not transferred to a cardiac center had a higher risk of neonatal mortality than infants who were delivered far from home and not transferred. Future studies should identify the barriers to delivery at a cardiac center for mothers experiencing poverty.

Design and methods for the training in exercise activities and motion for growth (TEAM 4 growth) trial: A randomized controlled trial

BACKGROUND

Growth is often impaired in infants with congenital heart disease. Poor growth has been associated with worse neurodevelopment, abnormal behavioral state, and longer time to hospital discharge. Nutritional interventions, drug therapy, and surgical palliation have varying degrees of success enhancing growth. Passive range of motion (PROM) improves somatic growth in preterm infants and is safe and feasible in infants with hypoplastic left heart syndrome (HLHS), after their first palliative surgery (Norwood procedure).

METHODS

This multicenter, Phase III randomized control trial of a 21-day PROM exercise or standard of care evaluates growth in infants with HLHS after the Norwood procedure. Growth (weight-, height- and head circumference-for-age z-scores) will be compared at 4 months of age or at the pre-superior cavopulmonary connection evaluation visit, whichever comes first. Secondary outcomes include neonatal neurobehavioral patterns, neurodevelopmental assessment, and bone mineral density. Eligibility include diagnosis of HLHS or other single right ventricle anomaly, birth at ≥37 weeks gestation and Norwood procedure at <30 days of age, and family consent. Infants with known chromosomal or recognizable phenotypic syndromes associated with growth failure, listed for transplant, or expected to be discharged within 14 days of screening are excluded.

CONCLUSIONS

The TEAM 4 Growth trial will make an important contribution to understanding the role of PROM on growth, neurobehavior, neurodevelopment, and BMD in infants with complex cardiac anomalies, who are at high risk for growth failure and developmental concerns.

Outcomes After Stage I Norwood Palliation in a Recently Established Program Can Achieve Results Similar to Longer Established Services

BACKGROUND

Infants with hypoplastic left heart syndrome (HLHS) or similar single ventricle cardiac lesions require a three-stage surgical approach, the first step being the Stage I Norwood procedure. The Queensland Children's Hospital (QCH) in Australia is a tertiary hospital providing the only cardiac surgical service to children in Queensland and northern New South Wales.

OBJECTIVE

To review the centre's outcomes of Norwood procedures performed in the last 6 years.

MATERIALS AND METHODS

We retrospectively evaluated all infants undergoing the stage I Norwood procedure between January 2015 and August 2021. Mortality, intensive care length of stay, events of cardiac arrest following surgery and duration of mechanical ventilation were calculated and analysed for subgroups depending on type of pulmonary shunt type (right-ventricle-to-pulmonary-artery shunt [RVPAS] vs the modified Blalock-Taussig shunt [MBTS]).

RESULTS

Forty-nine (49) patients were included. Overall survival to stage two operation (Glenn) was 90%. Both shunts were used evenly with the RVPA conduit preferred for HLHS and the MBTS largely chosen for hypoplastic left heart variants. In univariable analysis there was no difference in cardiac arrest or mortality rate for the patient with a RVPAS compared to the patient with a MBTS.

CONCLUSION

We show that a recently established Norwood program can achieve results that are comparable to those reported by longer established centres, and the international literature.

Critical Care Unit Organizational and Personnel Factors Impact Cardiac Arrest Prevention and Rescue in the Pediatric Cardiac Population

OBJECTIVES

Patient-level factors related to cardiac arrest in the pediatric cardiac population are well understood but may be unmodifiable. The impact of cardiac ICU organizational and personnel factors on cardiac arrest rates and outcomes remains unknown. We sought to better understand the association between these potentially modifiable organizational and personnel factors on cardiac arrest prevention and rescue.

DESIGN

Retrospective analysis of the Pediatric Cardiac Critical Care Consortium registry.

SETTING

Pediatric cardiac ICUs.

PATIENTS

All cardiac ICU admissions were evaluated for cardiac arrest and survival outcomes.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Successful prevention was defined as the proportion of admissions with no cardiac arrest (inverse of cardiac arrest incidence). Rescue was the proportion of patients surviving to cardiac ICU discharge after cardiac arrest. Cardiac ICU organizational and personnel factors were captured via site questionnaires. The associations between organizational and personnel factors and prevention/rescue were analyzed using Fine-Gray and multinomial regression, respectively, accounting for clustering within hospitals. We analyzed 54,521 cardiac ICU admissions (29 hospitals) with 1,398 cardiac arrest events (2.5%) between August 1, 2014, and March 5, 2019. For both surgical and medical admissions, lower average daily cardiac ICU occupancy was associated with better cardiac arrest prevention. Better rescue for medical admissions was observed for higher registered nursing hours per patient day and lower proportions of "part time" cardiac ICU physician staff (< 6 service weeks/yr). Increased registered nurse experience was associated with better rescue for surgical admissions. Increased proportion of critical care certified nurses, full-time intensivists with critical care fellowship training, dedicated respiratory therapists, quality/safety resources, and annual cardiac ICU admission volume were not associated with improved prevention or rescue.

CONCLUSIONS

Our multi-institutional analysis identified cardiac ICU bed occupancy, registered nurse experience, and physician staffing as potentially important factors associated with cardiac arrest prevention and rescue. Recognizing the limitations of measuring these variables cross-sectionally, additional studies are needed to further investigate these organizational and personnel factors, their interrelationships, and how hospitals can modify structure to improve cardiac arrest outcomes.

Transient and persistent acute kidney injury phenotypes following the Norwood operation: a retrospective study

BACKGROUND

Acute kidney injury is a common complication following the Norwood operation. Most neonatal studies report acute kidney injury peaking within the first 48 hours after cardiac surgery. The aim of this study was to evaluate if persistent acute kidney injury (>48 postoperative hours) after the Norwood operation was associated with clinically relevant outcomes.

METHODS

Two-centre retrospective study among neonates undergoing the Norwood operation. Acute kidney injury was initially identified as developing within the first 48 hours after cardiac surgery and stratified into transient (≤48 hours) and persistent (>48 hours) using the neonatal modification of the Kidney Disease: Improving Global Outcomes serum creatinine criteria. Severe was defined as stage ≥2. Primary and secondary outcomes were mortality and duration of ventilation and hospital length of stay.

RESULTS

One hundred sixty-eight patients were included. Transient and persistent acute kidney injuries occurred in 24 and 17%, respectively. Cardiopulmonary bypass and aortic cross clamp duration, and incidence of cardiac arrest were greater among those with persistent kidney injury. Mortality was four times higher (41 versus 12%, p < 0.001) and mechanical ventilation duration 50 hours longer in persistent acute kidney injury patients (158 versus 107 hours; p < 0.001). In multivariable analysis, persistent acute kidney injury was not associated with mortality, duration of ventilation or length of stay. Severe persistent acute kidney injury was associated with a 59% increase in expected ventilation duration (aIRR:1.59, 95% CI:1.16, 2.18; p = 0.004).

CONCLUSIONS

Future large studies are needed to determine if risk factors and outcomes change by delineating acute kidney injury into discrete timing phenotypes.

Associations With Extubation Failure and Predictive Value of Risk Analytics Algorithms With Extubation Readiness Tests Following Congenital Cardiac Surgery

OBJECTIVES

Extubation failure is associated with morbidity and mortality in children following cardiac surgery. Current extubation readiness tests (ERT) do not consider the nonrespiratory support provided by mechanical ventilation (MV) for children with congenital heart disease. We aimed to identify factors associated with extubation failure in children following cardiac surgery and assess the performance of two risk analytics algorithms for patients undergoing an ERT.

DESIGN

Retrospective cohort study.

SETTING

CICU at a tertiary-care children's hospital.

PATIENTS

Children receiving MV greater than 48 hours following cardiac surgery between January 1, 2017, and December 31, 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Six hundred fifty encounters were analyzed with 49 occurrences (8%) of reintubation. Extubation failure occurred most frequently within 6 hours of extubation. On multivariable analysis, younger age (per each 3-mo decrease: odds ratio [OR], 1.06; 95% CI, 1.001-1.12), male sex (OR, 2.02; 95% CI, 1.03-3.97), Society of Thoracic Surgery-European Association for Cardiothoracic Surgery category 5 procedure (p equals to 0.005), and preoperative respiratory support (OR, 2.08; 95% CI, 1.09-3.95) were independently associated with unplanned reintubation. Our institutional ERT had low sensitivity to identify patients at risk for reintubation (23.8%; 95% CI, 9.7-47.6%). The addition of the inadequate delivery of oxygen (IDO2) index to the ERT increased the sensitivity by 19.0% (95% CI, -2.5 to 40.7%; p = 0.05), but the sensitivity remained low and the accuracy of the test dropped by 8.9% (95% CI, 4.7-13.1%; p < 0.01).

CONCLUSIONS

Preoperative respiratory support, younger age, and more complex operations are associated with postoperative extubation failure. IDO2 and IVCO2 provide unique cardiorespiratory monitoring parameters during ERTs but require further investigation before being used in clinical evaluation for extubation failure.

Social Determinants of Disparities in Mortality Outcomes in Congenital Heart Disease: A Systematic Review and Meta-Analysis

Background

Social determinants of health (SDoH) affect congenital heart disease (CHD) mortality across all forms and age groups. We sought to evaluate risk of mortality from specific SDoH stratified across CHD to guide interventions to alleviate this risk.

Methods

We searched electronic databases between January 1980 and June 2019 and included studies that evaluated occurrence of CHD deaths and SDoH in English articles. Meta-analysis was performed if SDoH data were available in &gt;3 studies. We included race/ethnicity, deprivation, insurance status, maternal age, maternal education, single/multiple pregnancy, hospital volume, and geographic location of patients as SDoH. Data were pooled using random-effects model and outcome was reported as odds ratio (OR) with 95% confidence interval (CI).

Results

Of 17,716 citations reviewed, 65 met inclusion criteria. Sixty-three were observational retrospective studies and two prospective. Of 546,981 patients, 34,080 died. Black patients with non-critical CHD in the first year of life (Odds Ratio 1.62 [95% confidence interval 1.47–1.79], I2 = 7.1%), with critical CHD as neonates (OR 1.27 [CI 1.05-1.55], I2 = 0%) and in the first year (OR 1.68, [1.45-1.95], I2 = 0.3%) had increased mortality. Deprived patients, multiple pregnancies, patients born to mothers &lt;18 years and with education &lt;12 years, and patients on public insurance with critical CHD have greater likelihood of death after the neonatal period.

Conclusion

This systematic review and meta-analysis found that Black patients with CHD are particularly vulnerable for mortality. Numerous SDoH that affect mortality were identified for specific time points in CHD course that may guide interventions, future research and policy.

Systematic Review Registration

[https://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42019139466&amp;ID=CRD42019139466], identifier [CRD42019139466].

Right Ventricular Global Longitudinal Strain in Fetuses with Hypoplastic Left Heart Syndrome Does Not Differ Between Those With and Without Genetic Conditions

The presence of a genetic condition is a risk factor for increased mortality in hypoplastic left heart syndrome (HLHS). Speckle tracking strain analysis in interstage echocardiograms have shown promise in identifying patients with HLHS at increased risk of mortality. We hypothesized that fetuses with a genetic condition and HLHS have impaired right ventricular global longitudinal strain compared with fetuses with HLHS and no evident genetic condition. We performed a retrospective analysis of 60 patients diagnosed in fetal life with HLHS from 11/2015 to 11/2019. We evaluated presenting echocardiograms and calculated right ventricular global longitudinal strain (RV GLS) and fractional area of change (FAC) using post-processing software. We first compared RV GLS and FAC between those with genetic conditions to those without. We examined the secondary outcome of mortality among those with and without genetic conditions and among HLHS subgroups. Of the 60 patients with available genetic testing, 11 (18%) had an identified genetic condition. Neither RV GLS nor FAC was significantly different between patients with and without genetic conditions. There was no difference in RV GLS or FAC among HLHS phenotype or those who died or survived as infants. However, patients with a genetic syndrome had increased neonatal and overall mortality. In this cohort, RV GLS did not differ between those with and without a genetic diagnosis, among HLHS phenotypes, or between those surviving and dying as infants. Further analysis of strain throughout gestation and after birth could provide insight into the developing heart in fetuses with HLHS.

Surgical reintervention on the neo-aorta after the Norwood operation

OBJECTIVES

We sought to identify the prevalence of surgical reintervention on the neo-aorta after Norwood procedure and its impact on long-term outcomes.

METHODS

We reviewed the medical records of all patients who underwent Norwood procedure. The impacts of surgical neoaortic reintervention on outcomes were analysed in each stage of palliation.

RESULTS

A total of 335 patients were included in this study. Thirty patients underwent surgical reintervention on the neo-aorta after Norwood procedure. The timing of initial reintervention was before stage II in 13 patients, at stage II in 7, between stage II and stage III in 5, at stage III in 3 and after stage III in 2. A reintervention before stage II was significantly associated with mortality (HR 14.4, 95% confidence interval 6.00-34.6, P < 0.001). In patients who underwent stage II (n = 251), reintervention had no significant impact on mortality. In patients who underwent stage III (n = 188), the previous reintervention was significantly associated with higher mean pulmonary pressure (P = 0.05) and a higher rate of reduced ventricular function (P = 0.002). Greater than mild atrioventricular valve regurgitation was significantly associated with the development of a neoaortic arch stenosis after stage II (P = 0.03).

CONCLUSIONS

Surgical reinterventions on the neo-aorta were required in each inter-stage phase. A surgical neoaortic reintervention was not related to increased mortality after stage II but significantly associated with a higher rate of reduced ventricular function and elevated mean pulmonary artery pressure.