Characteristics of Interstage Death After Discharge from Stage I Palliation.

BACKGROUND: Interstage mortality (IM) remains high for patients with single-ventricle congenital heart disease (SVCHD) in the period between Stage 1 Palliation (S1P) and Glenn operation. We sought to characterize IM. METHODS: This was a descriptive analysis of 2184 patients with SVCHD discharged home after S1P from 60 National Pediatric Cardiology Quality Improvement Collaborative sites between 2008 and 2015. Patients underwent S1P with right ventricle-pulmonary artery conduit (RVPAC), modified Blalock-Taussig-Thomas shunt (BTT), or Hybrid; transplants were excluded. RESULTS: IM occurred in 153 (7%) patients (median gestational age 38 weeks, 54% male, 77% white), at 88 (IQR 60,136) days of life, and 39 (IQR 17,84) days after hospital discharge; 13 (8.6%) occurred ≤ 30 days after S1P. The mortality rate for RVPAC was lower (5.2%; 59/1138) than BTT (9.1%; 65/712) and Hybrid (20.1%; 27/134). More than half of deaths occurred at home (20%) or in the emergency department (33%). The remainder occurred while inpatient at center of S1P (cardiac intensive care unit 36%, inpatient ward 5%) or at a different center (5%). Fussiness and breathing problems were most often cited as harbingers of death; distance to surgical center was the biggest barrier cited to seeking care. Cause of death was unknown in 44% of cases overall; in the subset of patients who underwent post-mortem autopsy, the cause of death remained unknown in 30% of patients, with the most common diagnosis being low cardiac output. CONCLUSIONS: Most IM occurred in the outpatient setting, with non-specific preceding symptoms and unknown cause of death. These data indicate the need for research to identify occult causes of death, including arrhythmia.

Arterial duct stent versus surgical shunt for patients with duct-dependent pulmonary circulation: a meta-analysis.

BACKGROUND: Both systemic-pulmonary shunt and arterial duct stent could be the palliation of duct-dependent pulmonary circulation. We aimed to compare the safety and efficacy of the two approaches. METHODS: The PubMed, EMBASE, and Cochrane Library databases were searched through December 2019 for studies comparing stent implantation and surgical shunt in duct-dependent pulmonary circulation. The baseline characteristics included ventricle physiology and cardiac anomaly. The main outcomes were hospital stay and total mortality. Additional outcomes included procedural complications, intensive care unit (ICU) stay, pulmonary artery growth at follow-up, and other indexes. A random- or fixed-effects model was used to summarize the estimates of the mean difference (MD)/risk ratio (RR) with 95% confidence intervals (CIs). RESULTS: In total, 757 patients with duct-dependent pulmonary circulation from six studies were included. Pooled estimates of hospital stay (MD, - 4.83; 95% CI - 7.92 to - 1.74; p < 0.05), total mortality (RR 0.44; 95% CI 0.28-0.70; p < 0.05), complications (RR 0.49; 95% CI 0.30-0.81; p < 0.05) and ICU stay (MD, - 4.00; 95% CI - 5.96 to - 2.04; p < 0.05) favored the stent group. Significant differences were found in the proportions of patients with a single ventricle (RR 0.82; 95% CI 0.68-0.98; p < 0.05) or a double ventricle (RR 1.23; 95% CI 1.07-1.41; p < 0.05) between the stent and shunt groups. Additionally, pulmonary artery growth showed no significant differences between the two groups. CONCLUSION: Arterial duct stent appears to have not inferior outcomes of procedural complications, mortality, hospital and ICU stay, and pulmonary artery growth in selected patients compared with a surgical shunt. TRIAL REGISTRATION: CRD42019147672.

Anterograde blood flow associated with modified Blalock-Taussig shunt does not modify pulmonary artery growth compared with modified Blalock-Taussig shunt alone.

BACKGROUND: The main difference between extreme tetralogy of Fallot (TOF) and pulmonary atresia with ventricle septal defect (PA/VSD) is anterograde pulmonary blood flow (APBF). It is speculated that the association of modified Blalock-Taussig shunt (mBTS) with APBF favours shunt thrombosis, but promotes better pulmonary artery growth. AIM: To compare pulmonary artery growth after mBTS between TOF and PA/VSD. METHODS: From 1995 to 2018, 77 mBTS procedures were performed in infants (aged<1 year): 45 for TOF; 32 for PA/VSD. Using a 1/1 propensity score-matched analysis, 38 patients were included (19 per group). Delta Nakata was defined as the difference in the Nakata index before biventricular repair and before mBTS. RESULTS: After matching, the preoperative Nakata index was similar in the two groups (TOF 101±34 vs. PA/VSD 106±35 mm2/m2; P=0.75). Age and weight were similar (TOF 24±20 days, 3.3±0.6kg vs. PA/VSD 24±33 days, 3.3±0.9kg; P=0.84 and P=0.77, respectively). There was no difference in rates of in-hospital mortality (TOF 0% vs. PA/VSD 10%; P=0.13) or mBTS thrombosis (TOF 15% vs. PA/VSD 10%; P=0.63). The left and right pulmonary artery diameters at time of biventricular repair were similar (TOF 7.5±2.2 and 6.7±2.1 vs. PA/VSD 8±2.7 and 7.1±2.5mm; P=0.43 and P=0.78, respectively), as were delta Nakata (TOF 112±102 vs. PA/VSD 107±66 mm2/m2; P=0.89), median age for biventricular repair (P=0.83) and reintervention rates (TOF 10% vs. PA/VSD 15%; P=0.67). CONCLUSIONS: We found no difference in pulmonary artery growth between APBF with mBTS versus mBTS alone. Thus, we could not show an increase in mBTS thrombosis with APBF.

Red Blood Cell Transfusion After Stage I Palliation Is Associated With Worse Clinical Outcomes.

Background Packed red blood cell transfusion may improve oxygen content in single-ventricle neonates, but its effect on clinical outcomes after Stage 1 palliation is unknown. Methods and Results Retrospective multicenter analysis of packed red blood cell transfusion exposures in neonates after Stage 1 palliation, excluding those with intraoperative mortality or need for extracorporeal membrane oxygenation. Transfusion practice variability was assessed, and multivariable regression used to identify transfusion risk factors. After propensity score adjustment for severity of illness, clinical outcomes were compared between transfused and nontransfused subjects. Of 396 subjects, 323 (82%) received 930 postoperative red blood cell transfusions. Packed red blood cell volume (median 9-42 mL/kg [P<0.0001]), donor exposures (1-2 [P<0.0001]), transfusion number (1-3 [P<0.0001]), and pretransfusion hemoglobin (12.1-13 g/dL, P=0.0049) varied between sites. Cyanosis (P=0.02), chest tube output (P=0.0003), and delayed sternal closure (P=0.0033) increased transfusion risk. Transfusion was associated with prolonged mechanical ventilation (6 [interquartile range 4, 12] versus 3 [1, 5] days, P=0.02) and intensive care unit stay (19 [12, 33] versus 9 [6, 19] days, P=0.016). When stratified by number of transfusions (0, 1, or >1), duration of mechanical ventilation (3 [1, 5] versus 4 [3, 6] versus 9 [5, 16] days [P<0.0001]) and intensive care unit stay (9 [6, 19] versus 13 [8, 25] versus 21 [13, 38] days [P<0.0001]) increased for those transfused more than once. Most subjects who died were transfused, though the association with mortality was not significant. Conclusions Packed red blood cell transfusion after Stage 1 palliation is common, and transfusion practice is variable. Transfusion is a significant predictor of longer intensive care unit stay and mechanical ventilation. Further studies to define evidence-based transfusion thresholds are warranted.

Survival, Neurocognitive, and Functional Outcomes After Completion of Staged Surgical Palliation in a Cohort of Patients With Hypoplastic Left Heart Syndrome.

Background Management of patients with hypoplastic left heart syndrome has benefited from advancements in medical and surgical care. Outcomes have improved, although survival and long-term functional and cognitive deficits remain a concern. Methods and Results This is a cohort study of all consecutive patients with hypoplastic left heart syndrome undergoing surgical palliation at a single center. We aimed to examine demographic and perioperative factors from each surgical stage for their association with survival and neurocognitive outcomes. A total of 117 consecutive patients from 1996 to 2010 underwent surgical palliation. Seventy patients (60%) survived to the Fontan stage and 68 patients (58%) survived to undergo neurocognitive assessment at a mean (SD) age of 56.6 months (6.4 months). Full-scale, performance, and verbal intelligence quotient, as well as visual-motor integration mean (SD) scores were 86.7 (16.1), 86.3 (15.8), 88.8 (17.2), and 83.2 (14.8), respectively. On multivariable analysis, older age at Fontan, sepsis peri-Norwood, lowest arterial partial pressure of oxygen postbidirectional cavopulmonary anastomosis, and presence of neuromotor disability pre-Fontan were strongly associated with lower scores for all intelligence quotient domains. Older age at Fontan and sepsis peri-Norwood remained associated with lower scores for all intelligence quotient domains in a subgroup analysis excluding patients with disability pre-Fontan or with chromosomal abnormalities. Conclusions Older age at Fontan and sepsis are among independent predictors of poor neurocognitive outcomes for patients with hypoplastic left heart syndrome. Further studies are required to identify the appropriate age range for Fontan completion, balancing a lower risk of acute and long-term hemodynamic complications while optimizing long-term neurocognitive outcomes.

Development of a validated risk score for interstage death or transplant after stage I palliation for single-ventricle heart disease.

OBJECTIVE: To develop a risk score to predict mortality or transplant in the interstage period. BACKGROUND: The "interstage" period between the stage 1 and stage 2 palliation is a time of high morbidity and mortality for infants with single-ventricle congenital heart disease. METHODS: This was an analysis of patients with single-ventricle congenital heart disease requiring arch reconstruction who were enrolled in the National Pediatric Cardiology Quality Improvement Collaborative registry from 2008 to 2015. The primary composite endpoint was interstage mortality or transplant. Multivariable logistic regression and classification and regression tree analysis were performed on two-thirds of the patients ("learning cohort") to build a risk score for the composite endpoint, that was validated in the remaining patients ("validation cohort"). RESULTS: In the 2128 patients analyzed in the registry, the overall event rate was 9% (153 [7%] deaths, 42 [2%] transplants). In the learning cohort, factors independently associated with the composite endpoint were (1) type of Norwood; (2) postoperative ECMO; (3) discharge with Opiates; (4) No Digoxin at discharge; (5) postoperative Arch obstruction, (6) moderate-to-severe Tricuspid regurgitation without an oxygen requirement, and (7) Extra Oxygen required at discharge in patients with moderate-to-severe tricuspid regurgitation. This model was used to create a weighted risk score ("NEONATE" score; 0-76 points), with >75% accuracy in the learning and validation cohorts. In the validation cohort, the event rate in patients with a score >17 was nearly three times those with a score ≤17. CONCLUSIONS: We introduce a risk score that can be used post-stage 1 palliation to predict freedom from interstage mortality or transplant.

Pulmonary artery growth after Modified Blalock-Taussig shunt: A single center experience.

OBJECTIVE: This study evaluates growth of pulmonary artery (PA) between different age groups after Modified Blalock-Taussig shunt (MBTS) based on a single center experience. METHODS: We retrospective analyzed outcomes of 90 patients undergoing MBTS in our institute from January 1, 2010 to May 1, 2018. Patients were divided into three groups: Group 1, ≦2 months, Group 2, >2 months, ≦24 wmonths, Group 3, >24 months. The outcome included PA growth, overall survival rates and postoperative complications. RESULTS: 23 patients were involved in Group 1, while 49 in Group 2 and 18 in Group 3. The diameter of the PA, McGoon ratio, Nakata index and the oxygen saturation increased significantly after MBTS. Compared to pre-MBTS, there was no statistically significant increase of McGoon ratio in Group 3 after performing MBTS, but it witnessed less secondary cardiac surgery rate compared with Group 2 (11.11% vs. 48.98%, P = 0.005). Cumulative survival rates of three groups were 60.53%, 85.70%, 94.40% at 1 year; 60.53%, 78.30%, 87.75% at 3 years and 60.53%, 78.30%, 87.75% at 5 years. Multivariable analysis showed diastolic blood pressure <30 mmHg [OR 14.14 (1.92-104.32), P = 0.009], cardiopulmonary bypass use [OR 16.79 (2.05-137.67), P = 0.009] and single ventricle anomaly [OR 8.80 (1.18-65.54), P = 0.034] were predictors of perioperative mortality. CONCLUSION: MBTS in our institute is a conventional and effective procedure for growth of PA especially for patients younger than 24 months. Patients with biventricular anomaly, no cardiopulmonary bypass use in surgery and relatively high postoperative diastolic blood pressure will likely offer a good prognosis.

Comparison of Outcomes at Time of Superior Cavopulmonary Connection Between Single Ventricle Patients With Ductal-Dependent Pulmonary Blood Flow Initially Palliated With Either Blalock-Taussig Shunt or Ductus Arteriosus Stent: Results From the Congenital Catheterization Research Collaborative.

BACKGROUND: Patients with single ventricle anatomy and ductal-dependent pulmonary blood flow may be initially palliated with either modified Blalock-Taussig shunt (BTS) or ductus arteriosus stent (DAS). Comparisons of outcomes during the interstage period and at the time of superior cavopulmonary connection (SCPC) are lacking and may differ between palliation strategies. METHODS: Infants with single ventricle anatomy and ductal-dependent pulmonary blood flow palliated with either DAS or BTS from 2008 to 2015 were reviewed across 4 centers. Interstage outcomes, and for those who had SCPC, anatomy, hemodynamics, and perioperative clinical outcomes were compared. Thirty-five patients with DAS and 136 patients with BTS were included. RESULTS: At initial palliation, demographic, clinical variables, and pulmonary artery size were similar. Interstage death, transplant, or unplanned reintervention to treat cyanosis occurred in 25.7% of DAS and 35.8% of BTS, P=0.27. Reintervention was more common with DAS (48.6% versus 2.2%; P<0.001). Twenty-three DAS patients and 111 BTS patients underwent SCPC. Preoperative hemodynamics and overall pulmonary atresia growth were similar, although right pulmonary artery growth was better with DAS (change in z-score: 1.57 versus 0.65, P=0.026). SCPC intraoperative and postoperative courses were similar. CONCLUSIONS: In patients with single-ventricle anatomy and ductal-dependent pulmonary blood flow, interstage outcomes, hemodynamics before SCPC, and acute postoperative outcomes were similar. Overall reintervention was more common in the DAS group, driven by more frequent planned reintervention. Unplanned reintervention, death, and transplant were similar. Both groups demonstrated good pulmonary atresia growth. DAS is a reasonable initial palliative alternative to BTS in select patients.

Determinants of acute events leading to mortality after shunt procedure in univentricular palliation.

OBJECTIVE: The study objective was to identify determinants of adverse outcomes in patients undergoing univentricular palliation after the shunt procedure. METHODS: We performed a retrospective study of patients with univentricular lesions undergoing modified Blalock-Taussig shunt and central shunt placement, with or without concomitant Norwood/Damus-Kaye-Stansel procedures, between 2004 and 2014. RESULTS: Overall, 246 patients were included, with 150 patients undergoing concomitant Norwood/Damus-Kaye-Stansel procedure. The 30-day and in-hospital mortality were 7.3% and 14.6%, respectively. Progression to bidirectional cavopulmonary connection was achieved in 76% of patients. Acute events occurred in 66 patients (27%), with 42 having an acute event in the first 72 hours postoperatively. Of all in-hospital deaths, 75% had preceding acute events. On multivariable analysis, the risk factor for 30-day or in-hospital mortality was the incidence of an acute event (odds ratio [OR], 13.5; 95% confidence interval [CI], 5.51-36.4; P < .001). Postoperative pH was associated with fewer acute events (OR, 0.61 per 0.1 unit increase; 95% CI, 0.45-0.82; P = .002). Risk factors for shunt thrombosis associated with an acute event were increased postoperative hematocrit (OR, 2.12 per 0.1 unit increase; 95% CI, 1.01-4.58; P = .049) and 3.0-mm shunt size (OR, 3.78; 95% CI, 1.47-10.6; P = .007). Damus-Kaye-Stansel/Norwood procedure, shunt type, morphology, and extracardiac or genetic anomaly were not risk factors for mortality or acute events. CONCLUSIONS: More than one-fifth of patients shunted during univentricular palliation die before the second stage. The majority of these deaths are associated with acute events occurring early after surgery. Strategies to improve survival should focus on prevention and management of acute events.

Reasons for Failure of Systemic-to-Pulmonary Artery Shunts in Neonates.

BACKGROUND: Systemic-to-pulmonary artery shunt placement is an established palliative procedure for congenital heart disease. Although it is thought to be a simple operation, it is associated with significant morbidity and mortality. METHODS: Data for all neonates who underwent surgery for a systemic-to-pulmonary artery shunt between 2000 and 2016 were reviewed. The study endpoints were shunt failure and shunt-related mortality. Shunt failure was defined as a shunt dysfunction because of thrombosis or stenosis requiring intervention or reoperation; shunt mortality was defined as death because of a shunt dysfunction. RESULTS: A total of 305 shunts (central shunt, n = 135; Blalock-Taussig shunt, n = 170) were implanted in 280 patients. The median patients' age at the time of surgery was 9 days (1-31 days). The median shunt size was 3.5 mm (3-4 mm). Twenty-four patients (8%) were diagnosed with a shunt failure, with a median time of 7 days (0-438 days). Freedom from shunt failure at 1 year was 91.6% ± 2%. A shunt-related mortality was ascertained for 12 patients (4%). Freedom from shunt-related mortality at 1 year was 96% ± 1%. Perioperative platelet transfusion (p = 0.01), central shunt (p = 0.02), 3-mm shunt size (p = 0.02), and postoperative extra corporeal membrane oxygenation (ECMO) (p < 0.01) were identified as risk factors for shunt failure. Platelet transfusion (p = 0.04) and postoperative ECMO (p < 0.01) were further identified as risk factors for shunt mortality. CONCLUSION: Based on these data, we recommend implanting a modified Blalock-Taussig shunt of at least 3.5 mm in neonates. Perioperative platelet transfusion and postoperative ECMO increase the risk of shunt failure.

Major Adverse Events Following Over-Shunting Are Associated With Worse Outcomes Than Major Adverse Events After a Blocked Systemic-to-Pulmonary Artery Shunt Procedure.

OBJECTIVES: Causes of major adverse event after systemic-to-pulmonary shunt procedure are usually shunt occlusion or over-shunting. Outcomes categorized on the basis of these causes will be helpful both for quality improvement and prognostication. DESIGN: Retrospective cohort analysis of children who underwent a systemic-to-pulmonary shunt after excluding those who had it for Norwood or Damus-Kaye-Stansel procedure. SETTING: The Royal Children's Hospital, Melbourne, VIC, Australia. PATIENTS: From 2008 to 2015, 201 children who had a systemic-to-pulmonary shunt were included. INTERVENTIONS: Major adverse event is defined as one or more of cardiac arrest, chest reopening, or requirement for extracorporeal membrane oxygenation. Study outcome is a "composite poor outcome," defined as one or more of acute kidney injury, necrotizing enterocolitis, brain injury, or in-hospital mortality. MEASUREMENTS AND MAIN RESULTS: Median (interquartile range) age was 12 days (6-38 d) and median (interquartile range) time to major adverse event was 5.5 hours (2-17 hr) after admission. Overall, 36 (18%) experienced a major adverse event, and reasons were over-shunting (n = 17), blocked shunt (n = 13), or other (n = 6). Fifteen (88%) in over-shunting group suffered a cardiac arrest compared with two (15%) in the blocked shunt group (p < 0.001). The composite poor outcome was seen in 15 (88%) in over-shunting group, four (31%) in the blocked shunt group, and 56 (34%) in those who did not experience a major adverse event (p < 0.001). By multivariable analysis, predictors for composite poor outcome were major adverse event due to over-shunting (no major adverse event-reference; over-shunting odds ratio, 18.60; 95% CI, 3.87-89.4 and shunt-block odds ratio, 1.57; 95% CI, 0.46-5.35), single ventricle physiology (odds ratio, 4.70; 95% CI, 2.34-9.45), and gestation (odds ratio, 0.84/wk increase; 95% CI, 0.74-0.96). CONCLUSIONS: Infants who suffer major adverse event due to over-shunting experience considerably poorer outcomes than those who experience events due to shunt block. A mainly hypoxic event with maintenance of systemic perfusion (as often seen in a blocked shunt) is less likely to result in poorer outcomes than those after a hypoxic-ischemic event (commonly seen in over-shunting).

Risk Factors for Failure of Systemic-to-Pulmonary Artery Shunts in Biventricular Circulation.

Systemic-to-pulmonary artery shunt placement is an established palliative procedure for congenital heart disease, but it is associated with high morbidity and mortality. Data of all patients with biventricular circulation who underwent systemic-to-pulmonary artery shunt implantation between 2000 and 2016 were reviewed. Endpoints of the study were shunt failure and shunt-related mortality. Shunt failure was defined as any shunt dysfunction requiring intervention or reoperation. Shunt-related mortality was defined as death due to shunt dysfunction. A total of 217 shunts (central shunt, n = 131, Blalock-Taussig shunt, n = 86) were implanted in 178 patients. The median age of the patients was 98 days [1 day to 1.2 years]. Corrective surgery was performed at a median time of 0.6 years [3 months to 7 years] after shunt placement. Shunt failure was diagnosed in 21 patients (9.6%) at a median time of 14.6 days [0 days to 2 years]. Causes of shunt failure were stenosis (n = 11; 5%) and thrombosis (n = 10; 4.6%). The rate of freedom from shunt failure was 89.9 ± 2.6% at 1 year, the rate of shunt-related mortality was 3% (n = 5), and the rate of freedom from shunt-related mortality at 1 year was 97.5 ± 1%. Platelet transfusion was required in 43 patients (20%), all for postoperative thrombocytopenia. Perioperative platelet transfusion (p = 0.03) and shunt size of 3 mm (p = 0.03) were identified as risk factors for shunt failure. Shunt size of 3 mm was also identified as a risk factor for shunt-related mortality. The ideal shunt size in patients with biventricular circulation requiring a systemic-to-pulmonary artery shunt is 3.5 mm or larger. Platelet transfusion increases the risk of shunt failure and should be avoided. Type of shunt and diagnosis have no influence on morbidity or mortality after shunt placement.

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

BACKGROUND: Stage 1 palliation of hypoplastic left heart syndrome (HLHS) involves the Norwood procedure combined with a modified Blalock-Taussig shunt (mBTS) or right ventricle to pulmonary artery shunt (RVPAS). Short-term survival has been described previously, whereas longer-term outcomes remain a subject of debate. This meta-analysis aimed to describe the short and long-term survival outcomes of these two shunts, and explore factors that might influence survival. METHODS: Medline, Cochrane Libraries and EMBASE were systematically searched, and 32 studies were included for statistical synthesis, comprising 1348 mBTS and 1258 RVPAS patients. RESULTS: While early in-hospital survival was superior in the RVPAS group (RR=1.5, p<0.05, 95% CI: 1.21-1.85), this difference was lost from 2years post-stage 1 palliation (RR=0.91, p>0.05, 95% CI: 0.79-1.04), and maintained unchanged up to 6years. This shift in survival was also reflected in inter-stage survival, with superior RVPAS outcomes between stage 1 and 2 (RR=1.62, p<0.05, 95% CI: 1.39-1.88), and equivalent outcomes between stage 2 and 3. Potential contributors to this included a significantly higher rate of pulmonary artery stenosis in the RVPAS group and an increased requirement for shunt re-intervention in this group prior to stage 2. CONCLUSIONS: Despite early advantages, RVPAS and mBTS for palliation of hypoplastic left heart syndrome produced comparable long-term survival. The RVPAS patients experienced more pulmonary artery stenosis and requirement for shunt re-intervention. The impact of shunt type on quality and survival with a Fontan is yet to be assessed.

Heparin-Coated Grafts Reduce Mortality in Pediatric Patients Receiving Systemic-to-Pulmonary Shunts.

We aimed to evaluate the outcomes of systemic-to-pulmonary (SP) shunt procedures utilizing heparin-coated (HC) polytetrafluoroethylene (PTFE) vascular grafts compared to uncoated (non-HC) grafts, in order to observe any benefits in pediatric patients. Our institution switched from using non-HC grafts to HC grafts in March 2011. We conducted a retrospective review of consecutive pediatric patients receiving SP shunts from May 2008 to December 2015. Perioperative variables including baseline characteristics, morbidity, mortality, and blood product utilization were evaluated between the HC and non-HC groups. A total of 142 pediatric patients received SP shunts during the study period: 69 patients received HC shunts and 73 patients received non-HC shunts. The HC group had significantly fewer desaturation or arrest events (P < 0.01), fewer shunt occlusions/thromboses (P < 0.01). There was no statistically significant difference in unplanned reoperations between groups (P = 0.18). The HC group demonstrated significantly lower overall 30-day mortality (P < 0.01), as well as shunt-related mortality (P < 0.01). The HC group had significantly lower postoperative packed red blood cell utilization as compared to the non-HC group (P < 0.01). In this study, pediatric patients receiving HC PTFE grafts in SP shunts demonstrated significantly lower shunt-related mortality. The majority of HC grafts remained patent. These findings suggest that HC grafts used in SP shunt procedures may benefit pediatric patients in terms of efficacy and outcomes.

Duct Stenting Versus Modified Blalock-Taussig Shunt in Neonates With Duct-Dependent Pulmonary Blood Flow: Associations With Clinical Outcomes in a Multicenter National Study.

BACKGROUND: Infants born with cardiac abnormalities causing dependence on the arterial duct for pulmonary blood flow are often palliated with a shunt usually between the subclavian artery and either pulmonary artery. A so-called modified Blalock-Taussig shunt allows progress through early life to an age and weight at which repair or further more stable palliation can be safely achieved. Modified Blalock-Taussig shunts continue to present concern for postprocedural instability and early mortality such that other alternatives continue to be explored. Duct stenting (DS) is emerging as one such alternative with potential for greater early stability and improved survival. METHODS: The purpose of this study was to compare postprocedural outcomes and survival to next-stage palliative or reparative surgery between patients undergoing a modified Blalock-Taussig shunt or a DS in infants with duct-dependent pulmonary blood flow. All patients undergoing cardiac surgery and congenital interventions in the United Kingdom are prospectively recruited to an externally validated national outcome audit. From this audit, participating UK centers identified infants <30 days of age undergoing either a Blalock-Taussig shunt or a DS for cardiac conditions with duct-dependent pulmonary blood flow between January 2012 and December 31, 2015. One hundred seventy-one patients underwent a modified Blalock-Taussig shunt, and in 83 patients, DS was attempted. Primary and secondary outcomes of survival and need for extracorporeal support were analyzed with multivariable logistic regression. Longer-term mortality before repair and reintervention were analyzed with Cox proportional hazards regression. All multivariable analyses accommodated a propensity score to balance patient characteristics between the groups. RESULTS: There was an early (to discharge) survival advantage for infants before next-stage surgery in the DS group (odds ratio, 4.24; 95% confidence interval, 1.37-13.14; P=0.012). There was also a difference in the need for postprocedural extracorporeal support in favor of the DS group (odds ratio, 0.22; 95% confidence interval, 0.05-1.05; P=0.058). Longer-term survival outcomes showed a reduced risk of death before repair in the DS group (hazard ratio, 0.25; 95% confidence interval, 0.07-0.85; P=0.026) but a slightly increased risk of reintervention (hazard ratio, 1.50; 95% confidence interval, 0.85-2.64; P=0.165). CONCLUSIONS: DS is emerging as a preferred alternative to a surgical shunt for neonatal palliation with evidence for greater postprocedural stability and improved patient survival to destination surgical treatment.

Comparison Between Patent Ductus Arteriosus Stent and Modified Blalock-Taussig Shunt as Palliation for Infants With Ductal-Dependent Pulmonary Blood Flow: Insights From the Congenital Catheterization Research Collaborative.

BACKGROUND: Infants with ductal-dependent pulmonary blood flow may undergo palliation with either a patent ductus arteriosus (PDA) stent or a modified Blalock-Taussig (BT) shunt. A balanced multicenter comparison of these 2 approaches is lacking. METHODS: Infants with ductal-dependent pulmonary blood flow palliated with either a PDA stent or a BT shunt from January 2008 to November 2015 were reviewed from the 4 member centers of the Congenital Catheterization Research Collaborative. Outcomes were compared by use of propensity score adjustment to account for baseline differences between groups. RESULTS: One hundred six patients with a PDA stent and 251 patients with a BT shunt were included. The groups differed in underlying anatomy (expected 2-ventricle circulation in 60% of PDA stents versus 45% of BT shunts; P=0.001) and presence of antegrade pulmonary blood flow (61% of PDA stents versus 38% of BT shunts; P<0.001). After propensity score adjustment, there was no difference in the hazard of the primary composite outcome of death or unplanned reintervention to treat cyanosis (hazard ratio, 0.8; 95% confidence interval [CI], 0.52-1.23; P=0.31). Other reinterventions were more common in the PDA stent group (hazard ratio, 29.8; 95% CI, 9.8-91.1; P<0.001). However, the PDA stent group had a lower adjusted intensive care unit length of stay (5.3 days [95% CI, 4.2-6.7] versus 9.19 days [95% CI, 7.9-10.6]; P<0.001), a lower risk of diuretic use at discharge (odds ratio, 0.4; 95% CI, 0.25-0.64; P<0.001) and procedural complications (odds ratio, 0.4; 95% CI, 0.2-0.77; P=0.006), and larger (152 mm2/m2 [95% CI, 132-176] versus 125 mm2/m2 [95% CI, 113-138]; P=0.029) and more symmetrical (symmetry index, 0.84 [95% CI, 0.8-0.89] versus 0.77 [95% CI, 0.75-0.8]; P=0.008] pulmonary arteries at the time of subsequent surgical repair or last follow-up. CONCLUSIONS: In this multicenter comparison of palliative PDA stent and BT shunt for infants with ductal-dependent pulmonary blood flow adjusted for differences in patient factors, there was no difference in the primary end point, death or unplanned reintervention to treat cyanosis. However, other markers of morbidity and pulmonary artery size favored the PDA stent group, supporting PDA stent as a reasonable alternative to BT shunt in select patients.

Determinants of Adverse Outcomes After Systemic-To-Pulmonary Shunts in Biventricular Circulation.

BACKGROUND: Systemic-to-pulmonary shunts are useful palliative procedures, although many teams have been deterred by high mortality and morbidity. We aimed to identify predictors of adverse outcomes after shunts in biventricular lesions. METHODS: From 2004 to 2014, 173 children had shunt procedures. Morphologies included: tetralogy of Fallot, pulmonary atresia with ventricular septal defect (VSD) with and without major aortopulmonary collaterals (MAPCAs), transposition of great arteries with pulmonary stenosis, and double outlet right ventricle. Median age was 22 days (range, 3 to 3,438 days) and median weight 3.2 kg (range, 1.7 to 20 kg). Shunt sizes ranged from 3 to 5 mm with median shunt size/weight ratio 1.03 mm/kg (range, 0.3 to 2.5 mm/kg). RESULTS: In-hospital mortality was 5.2% for the initial shunt procedure. Inter-stage mortality was 3.6%. Overall, 86% of patients progressed to corrective surgery. Acute events were observed in 41 patients, leading to 6 deaths. Events included 30 emergency chest openings, 16 shunt thrombosis, and 17 pulmonary overcirculation. Independent predictors of acute events or in-hospital mortality were genetic or extracardiac anomalies (hazard ratio [HR] = 1.9, p = 0.04), and preoperative shock/acidosis (HR = 2.73, p = 0.003). Diagnosis of pulmonary atresia with VSD and MAPCAs was protective (HR = 0.23, p = 0.042). Weight, shunt size, and size/weight ratios were not significant risk factors. Shunt thrombosis occurred at a median 3 hours (range, 0 to 46 hours) postoperatively, leading to 33% of in-hospital deaths. Low postoperative oxygen saturation and higher platelet counts in intensive care were independent predictors of thrombosis (p = 0.022, p = 0.005 respectively). CONCLUSIONS: Early adverse events contribute to mortality and morbidity for the shunt procedure. Patients with lower oxygen saturation and higher platelet counts in the postoperative period are at higher risk of shunt thrombosis.

Right ventricular outflow tract stent versus BT shunt palliation in Tetralogy of Fallot.

OBJECTIVE: This study sets out to compare morbidity, mortality and reintervention rates after stenting of the right ventricular outflow tract (RVOT) versus modified Blalock-Taussig shunt (mBTS) for palliation in patients with tetralogy of Fallot (ToF)-type lesions. METHODS: Retrospective case review study evaluating 101 patients (64 males) with ToF lesions who underwent palliation with either mBTS (n=41) or RVOT stent (n=60) to augment pulmonary blood flow over a 10-year period. Procedure-related morbidity, mortality and reintervention rates were assessed and compared. RESULTS: Admission rate to paediatric intensive care unit (PICU) was lower in the RVOT stent group (22% vs 100%; p<0.001). Thirty-day mortality in the RVOT stent group was (1/60 (1.7%)) compared with (2/41 (4.9%)) in the mBTS group (p=0.565). Mortality until surgical repair was comparable in both groups (5/60, 8.4%, including three non-cardiac death in the RVOT stent group vs 2/41, 4.9% (p=0.698)). Total hospital length of stay was shorter for the RVOT stent group (median 7 days vs 14 days; p<0.003). Time to surgical repair was shorter in the RVOT stent group (median 232 days, IQR 113-360) compared with the mBTS group (median 428 days, IQR 370-529; p<0.001) due to improved pulmonary arterial growth. CONCLUSION: RVOT stenting in Fallot-type lesions can be accomplished safely, with lower PICU admission rate, a shorter hospital length of stay and shorter duration of palliation until complete repair compared with mBTS palliation.

Outcomes of Blalock-Taussig shunts in current era: A single center experience.

OBJECTIVES: Mortality associated with the modified Blalock-Taussig shunt (MBTS) remains high despite advanced perioperative management. This study was formulated to provide data on (1) current indications, (2) outcomes, and (3) factors affecting mortality and morbidity. DESIGN: A retrospective single center chart review identified 95 children (excluding hypoplastic left heart lesions) requiring a MBTS. Mortality and major morbidity were analyzed using the Kaplan Meier method and risk factor analysis using Cox's proportional hazard regression. RESULTS: Median age was 8 (0-126) days, weight 3.1(1.7-5.4) kg. Seventy-three percent were neonates, 58% duct dependent and 73% had single ventricle physiology. Ninety-seven percent had a sternotomy approach for shunt placement with 70% receiving a 3.5 mm graft. Mean graft index (shunt cross sectional area [mm2 ]/BSA [m2 ]) was 44.39 ± 8.04 and shunt size (mm) to body weight (kg) ratio 1.1 ± 0.2. Hospital mortality was 12%, with an interval mortality of 6%. Shunt thrombosis/stenosis occurred in 23% and pulmonary over circulation in 30%, while shunt reoperation was required in 12% and catheter intervention in 8% of the cohort. At 1-year, survival was 82.0% (95% CI [72.7%, 88.4%]), and survival free of major morbidity 61.4% (95% CI [50.7%, 70.5%]). Duct dependency predisposed to mortality (P = .01, HR 6.74 [1.54, 29.53]) and composite outcome (mortality and major morbidity) (P = .04, HR 2.15, CI [1.036, 4.466]) and higher graft index to mortality (P = .005, HR 1.07 [1.02, 1.12]). CONCLUSIONS: The commonest indication for a MBTS in the current era was single ventricle palliation. Morbidity and mortality was considerable, partly explained by the higher at risk population. Alternative methods to maintain pulmonary blood flow in place of a MBTS requires further investigation.

Is a hybrid strategy a lower-risk alternative to stage 1 Norwood operation?

BACKGROUND: For neonates with critical left ventricular outflow tract obstruction (LVOTO), hybrid procedures are an alternative to the Norwood stage 1 procedure. Despite perceived advantages, however, outcomes are not well defined. Therefore, we compared outcomes after stage 1 hybrid and Norwood procedures. METHODS: In a critical LVOTO inception cohort (2005-2014; 20 institutions), a total of 564 neonates underwent stage 1 palliation with the Norwood operation with a modified Blalock-Taussig shunt (NW-BT; n = 232; 41%), Norwood operation with a right ventricle-to-pulmonary artery conduit (NW-RVPA; n = 222; 39%), or a hybrid procedure (n = 110; 20%). Post-stage 1 outcomes were analyzed via competing-risks and parametric hazard analyses and compared among all 564 patients and between patients who underwent propensity-matched hybrid and those who underwent NW-BT/NW-RVPA. RESULTS: By 6 years after the stage 1 operation, 50% ± 3%, 7% ± 2%, and 4% ± 1% of patients transitioned to Fontan, transplantation, and biventricular repair, respectively, whereas 7% ± 2% were alive without transition and 32% ± 2% died. Risk factors for death without transition included procedure type, smaller ascending aorta, aortic valve atresia, and lower birth weight. Risk-adjusted 4-year survival was better after NW-RVPA than after NW-BT or hybrid (76% vs 60% vs 61%; P < .001). Furthermore, for neonates with lower birth weight (<∼2 kg), an interaction between birth weight and hybrid resulted in a trend toward better survival after hybrid compared with NW-BT or NW-RVPA. For propensity-matched neonates between hybrid and NW-BT (88 pairs), 4-year survival was similar (62% vs 57%; P = .58). For propensity-matched neonates between hybrid and NW-RVPA (81 pairs), 4-year survival was better after NW-RVPA (59% vs 75%; P = .008). CONCLUSIONS: For neonates with critical LVOTO undergoing single-ventricle palliation, NW-RVPA was associated with the best overall survival. Hybrid strategies are not a lower-risk alternative to Norwood operations overall; however, the impact of lower birth weight on survival may be mitigated after hybrid procedures compared with Norwood operations.