Shunt Failure—Risk Factors and Outcomes: An Analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

Outcomes and Risk Factors for Morbidity and Mortality of Systemic-to-Pulmonary Shunts in a Tertiary Hospital in Thailand

OBJECTIVES

A systemic-to-pulmonary shunt is the palliation of choice for many children with cyanotic congenital heart disease. However, significant morbidity and mortality related to these procedures and the postoperative course still exists. We aim to report our outcomes of systemic-to-pulmonary shunts as well as to define certain risk factors for adverse events.

MATERIALS AND METHODS

We retrospectively collected data from the electronic medical records of Ramathibodi hospital from January 01, 2013, to April 30, 2024. Demographic data, operative, and postoperative details were collected and reviewed. Inclusion criteria included patients whose primary operation was a systemic-to-pulmonary shunt. Exclusion criteria were patients diagnosed with hypoplastic left heart syndrome and whose medical record data were missing significant information.

RESULTS

There were initially 56 patients eligible for our study. After exclusion, the total number of patients enrolled was 42. Overall the results were excellent, with only one operative mortality, no discharge mortality, and four reinterventions. Outcomes between different shunt types, shunt sizes, surgical approaches, and diagnoses were statistically similar.

CONCLUSIONS

We demonstrate that systemic-to-pulmonary shunts are a safe and reliable procedure based on our results at a tertiary hospital in Thailand. We emphasize meticulous surgical techniques as well as utilization of proper and reproducible postoperative care protocols to optimize patient outcomes.

Comparison of Blalock-Taussig-Thomas Shunts With Patent Ductus Arteriosus Ligated Versus Left Open

BACKGROUND

The optimal approach to patent ductus arteriosus management during systemic-to-pulmonary artery shunt placement is currently unknown. The purpose of this study is to examine the outcomes of variable strategies for patent ductus arteriosus management during Blalock-Taussig-Thomas shunt surgery.

METHODS

A retrospective cohort study of infants who underwent shunt placement was performed, comparing those who had the ductus ligated with those who had the ductus left open. Indicators of low cardiac output syndrome, development of necrotizing enterocolitis, and secondary outcomes such as resuscitation events were examined.

RESULTS

Thirty-six infants were included all of whom had their shunt placed via median sternotomy. Twenty infants had their ductus ligated at the time of the shunt, and they were compared with 16 infants whose ductus was left open. There was no statistical difference in preoperative baseline characteristics, including corrected gestational age, age in days, weight, mechanical ventilation, vasoactive use, heterotaxy, and gastrointestinal anomalies. There was also no statistical difference in postoperative indicators of low cardiac output, including urine production, total fluids given, renal injury, maximum lactate, and vasoactive-inotropic score. Three patients had postoperative renal injury, and all were in the ligated duct group. There was also no statistical difference in any secondary outcomes, including the development of necrotizing eneterocolitis, resuscitation events, reinterventions, length of intubation, total length of stay, and mortality.

CONCLUSIONS

This study provides evidence that variable management of the ductus during shunt placement does not significantly impact outcomes. Leaving the ductus open allows for a potential rescue source of pulmonary blood flow and does not appear to increase the risk of postoperative low cardiac output.

Safety of drug-eluting stents for stenting patent arterial duct in neonates

OBJECTIVES

The primary objective was to evaluate the trend of blood sirolimus concentrations in neonates following ductal stenting. The long-term outcomes and incidence of infections were also evaluated.

METHODS

Prospective open-label observational study in a tertiary referral centre over a 1-year period. Serum sirolimus levels were estimated at 1 hour and 24hrs post-stent insertion followed by 7 days in neonates who underwent ductal stenting. The trend in sirolimus levels, incidence of infections, complications and outcomes following ductal stenting were studied.

RESULTS

Seven neonates with duct-dependent pulmonary circulation underwent ductal stenting at median age of 8.5 days and weight of 2.83kg. The average stent size was 3.5±0.4 mm, and average stent length was 16.3±5.1 mm. The mean sirolimus concentrations at 1 hour, 24 hours and 7 days were 41.3±6.9ng/ml, 15.4±7.1ng/ml and 3.1±0.85ng/ml respectively. Levels fell below therapeutic range for all patients by 7 days. Three patients had sepsis or necrotising enterocolitis, but responded well to antibiotics; 1 patient had aspiration related sudden death. There were no further events at a mean follow-up of 207 days, and 4 patients underwent elective surgery at 238 ± 81 days after ductal stenting.

CONCLUSIONS

This study demonstrates applicability of drug-eluting stents for ductal stenting in newborns. Drug-eluting stents with abluminal drug delivery are associated with high sirolimus levels in initial hours but rapidly taper to negligible levels within a week of implantation. Neonates with high pre-procedure likelihood of infection developed sepsis but responded well to conservative management. The patency of drug-eluting ductal stents is preserved over long-term follow-up.

A Narrative Review of Multiinstitutional Data Registries of Pediatric Congenital Heart Disease in Pediatric Cardiac Anesthesia and Critical Care Medicine

Congenital heart disease (CHD) is one of the most common birth anomalies. While the care of children with CHD has improved over recent decades, children with CHD who undergo general anesthesia remain at increased risk for morbidity and mortality. Electronic health record systems have enabled institutions to combine data on the management and outcomes of children with CHD in multicenter registries. The application of descriptive analytics methods to these data can improve clinicians' understanding and care of children with CHD. This narrative review covers efforts to leverage multicenter data registries relevant to pediatric cardiac anesthesia and critical care to improve the care of children with CHD.

Outcome after stage 1 palliation in non-hypoplastic left heart syndrome patients as a univentricular palliation

OBJECTIVES

Studies focused on infants with univentricular heart undergoing stage I palliation other than the Norwood procedure remain a topic of great interest. This study evaluated the outcome of infants who underwent systemic to pulmonary shunt (SPS) or pulmonary artery banding (PAB).

METHODS

Infants who underwent SPS or PAB as stage I palliation between 1994 and 2019 were included. Survival and late systemic ventricular function were evaluated.

RESULTS

Out of 242 patients, 188 underwent SPS (77.7%) and 54 PAB (22.3%). Main diagnosis included tricuspid atresia, unbalanced atrioventricular septal defects, double inlet left ventricles and single ventricles with other morphology. Thirty-eight patients died before stage II palliation (15.7%). Stage II palliation was performed in 182 patients (75.2%), and mortality between stages II and III was 11 (5.6%). Stage III palliation was performed in 160 (66.1%) patients. Survival at 1, 5 and 15 years after stage I procedure was 81.9, 77.1 and 76.2%, respectively, and similar between both procedures (P = 0.97). Premature birth [P = 0.03, hazard ratio (HR) = 2.1], heterotaxy (P = 0.006, HR = 2.4) and dominant right ventricle (P = 0.015, HR = 2.2) were factors associated to mortality. Unbalanced atrioventricular septal defect (P = 0.005, HR = 4.6) was a factor associated to systemic ventricular dysfunction.

CONCLUSIONS

In patients with univentricular heart who underwent SPS and PAB as stage I palliation, survival at 15 years was 76%, regardless of th chosen approach. Premature birth, heterotaxy and dominant right ventricle were associated to mortality.

Contactless Ultrasonic Cavitation for the Prevention of Shunt Obstruction in Hydrocephalus: A Proof-of-Concept Study

BACKGROUND

Obstructive failure of implanted shunts is the most common complication in the treatment of hydrocephalus. Biological material and debris accumulate in the inner walls of the valve and catheters block the normal flow of the drained cerebrospinal fluid causing severe symptoms with high morbidity and mortality. Unfortunately, at present, there is no effective preventive protocol or cleaning procedure available.

OBJECTIVE

To assess whether externally applied, focused ultrasound beams can be used to resuspend deposits accumulated in brain shunts safely.

METHODS

A computational model of an implanted brain shunt was implemented to test the initial design parameters of a system comprising several ultrasound transducers. Under laboratory conditions, configurations with 3 and 4 transducers were arranged in a triangle and square pattern with their radiation axis directed towards a target model of the device, 2 catheters and a brain shunt filled with water and deposited graphite powder. The ultrasound beams were then concentrated on the device across a head model.

RESULTS

The computational model revealed that by using only 3 transducers, the acoustic field intensity on the valve was approximately twice that on the brain surface suggesting that acoustic cavitation could be selectively achieved. Resuspension of graphite deposits inside the catheters and the valve were then physically demonstrated and video-recorded with no temperature increase.

CONCLUSION

The technology presented here has the potential to be used routinely as a noninvasive, preventive cleaning procedure to reduce the likelihood of obstruction-related events in patients with hydrocephalus treated with an implanted shunt.

Impact of total anomalous pulmonary venous connection in staged single ventricle palliation

BACKGROUND

Total anomalous pulmonary venous connection (TAPVC) with a functional single ventricle is a risk factor for mortality during staged palliation. This study aimed to assess TAPVC's impact on staged palliation outcomes.

METHODS

In a total of 602 patients with a functional single ventricle who underwent stage 1 palliation (S1P) at our center between 2001 and 2020, 39 (6.5%) patients were associated with TAPVC. Median age at S1P was 12.0 (interquartile range, 7-21) days with a body weight of 3.1 (interquartile range, 2.8-3.6) kg. Outcomes during staged palliation were compared with the remaining 563 patients without TAPVC. Risk factors for mortality were identified using a Cox proportional hazards regression model.

RESULTS

Primary diagnosis in functional single-ventricle patients with TAPVC included hypoplastic left heart syndromes (n = 13), unbalanced atrioventricular septal defects (n = 12) tricuspid atresias (n = 2), double inlet left ventricle (n = 1), and others (n = 11). Types of TAPVC were supracardiac (n = 21), cardiac (n = 10), infracardiac (n = 6), and mixed (n = 2). Pulmonary venous obstruction (PVO) was associated in 19 (49%) patients. S1Ps included Norwood (n = 13), aortopulmonary shunt (n = 21), and pulmonary artery banding (n = 5). Thirty-day mortality after S1P was significantly increased in patients with TAPVC vs without TAPVC (43.6% vs 16.3%; P < .001). After bidirectional cavopulmonary shunt and total cavopulmonary connection procedures, mortality was low in both groups, and no statistically significant differences were found. Correction of TAPVC at the time of S1P was not found to be a significant risk factor in univariable Cox regression analysis. In univariate and multivariate analysis, PVO was identified as an independent risk factor for mortality in patients with TAPVC (P < .001).

CONCLUSIONS

Overall survival is lower in TAPVC single-ventricle patients than in non-TAPVC patients. Most deaths after S1P were associated with TAPVC, but not after S2P. PVO is a mortality risk factor in TAPVC patients.

Current evidence for pharmacologic therapy following stage 1 palliation for single ventricle congenital heart disease

INTRODUCTION

Infants with single ventricle congenital heart disease are vulnerable to complications between stage 1 and stage 2 of palliation. Pharmaceutical treatment during this period is varied and often dependent on institutional practices as there is little evidence supporting a particular treatment path.

AREAS COVERED

This review focuses on medical management of patients following stage I palliation. We performed a scoping review of the current literature regarding angiotensin converting enzyme inhibitors and digoxin treatment in the interstage period. In addition, we discuss other medication classes frequently used in these patients.

EXPERT OPINION

Due to significant heterogeneity of anatomy, rarity of disease, and other confounding factors, there is limited evidence to support most commonly used medications within the interstage period. Digoxin is associated with improved mortality within the interstage period and should be considered; however, no large randomized controlled trial exists supporting its use. Prevention of thrombotic complication with aspirin is also associated with improved outcomes and should be considered unless a contraindication exists. The addition of other prescriptions in this patient population should be considered only after an evaluation of the risks and benefits of each medication, recognizing the burden and risk of polypharmacy in this fragile patient population.

Type I and II pulmonary atresia with intact ventricular septum in infants: a 10-year experience in initial surgery at one center

Background

To explore the effect of initial surgery for type I and II pulmonary atresia with intact ventricular septum (PA/IVS).

Methods

50 children with type I PA/IVS and 50 with type II PA/IVS who had undergone initial surgery were enrolled. Children with Type I were divided into groups A (n = 25) and B (n = 25). Group A had received BT shunt combined with PDA ligation and balloon dilatation of pulmonary valve, whereas group B had undergone BT shunt combined with PDA ligation and pulmonary valve incision. Children with type II were divided into groups C (n = 25) and D (n = 25). Group C had received BT shunt combined with PDA ligation, right ventricular outflow tract (RVOT) incision and transannular patch. Group D had undergone BT shunt combined with PDA ligation, RVOT incision, transannular patch and artificial pulmonary valve implantation. The differences in mechanical ventilation time, length of ICU stay, mortality rate, tricuspid Z value, tricuspid regurgitation, oxygen saturation, pulmonary regurgitation, McGoon ratio, pulmonary artery transvalvular pressure, survival rate were compared between groups A and B, between groups C and D respectively.

Results

The ventilator assistance time and length of ICU stay were greater in group C than in group D (80.96 ± 8.42 h vs. 65.16 ± 4.85 h, P = 0.045; 222.00 ± 11.72 h vs. 162.48 ± 7.91 h, P = 0.048). The pulmonary artery transvalvular pressure was significantly higher in group A than in group B at 3, 6, 12, 24 and 36 months after surgery (64.86 ± 4.13 mmHg vs. 53.04 ± 5.64 mmHg, P = 0.045; 69.47 ± 1.93 mmHg vs. 55.95 ± 4.04 mmHg, P = 0.005; 80.16 ± 3.76 mmHg vs. 73.24 ± 2.34 mmHg, P = 0.035; 62.95 ± 5.64 mmHg vs. 48.47 ± 7.44 mmHg, P = 0.04; 53.69 ± 4.89 vs. 45.77 ± 3.26, P = 0.02). Furthermore, the tricuspid Z value was significantly greater in group B than in group A at 3 and 24 months after surgery (− (1.37 ± 0.04) vs. − (1.43 ± 0.06), P = 0.03; − (0.41 ± 0.06) vs. − (0.51 ± 0.11), P = 0.02).

Conclusions

The effect of BT shunt combined with PDA ligation and pulmonary valve incision is superior to BT shunt combined with PDA ligation and balloon dilatation of pulmonary valve, and the effect of BT shunt combined with PDA ligation, RVOT incision, transannular patch and artificial pulmonary valve implantation is superior to BT shunt combined with PDA ligation, RVOT incision and transannular patch.

In-hospital Morbidity and Mortality Following Modified Blalock-Taussig-Thomas Shunts

BACKGROUND

The modified Blalock-Taussig-Thomas shunt (mBTTs) is a critically important palliation for patients with insufficient pulmonary blood flow associated with congenital heart disease. Following creation of a mBTTs, patients experience high rates of early postoperative morbidity and mortality.

METHODS

This is a single-institution retrospective cohort study. A query of the Society of Thoracic Surgeons database identified relevant patients whose health records were manually queried for echocardiography and operative reports. Patients with ductal-dependent systemic circulation were excluded. Primary outcomes were early serious adverse events and in-hospital mortality. Secondary outcomes were time to primary outcomes and postoperative lengths of stay. We investigated the correlation of demographics, presence of competitive pulmonary blood flow, and surgical and anatomic factors on outcomes.

RESULTS

After exclusions, our cohort resulted in 155 patients. 33 (21.3%) patients experienced an early serious adverse event, ten (6.5%) early shunt malfunction, and 11 (7.1%) in-hospital mortality. Smaller shunt size, smaller shunted pulmonary artery size, surgical approach, and site of proximal shunt anastomosis were independently associated with morbidity and mortality.

CONCLUSIONS

Anatomical elements imparting increased resistance along the mBTTs predispose to increased morbidity and mortality, particularly in the early postoperative period. Despite the significant heterogeneity of patients receiving such shunts, similar risk profiles are observed regardless of lesion or presence of competitive flow. Surgical approach via thoracotomy with shunt anastomosis to the subclavian artery, where feasible, results in the subclavian artery as the point of natural resistance allowing for placement of larger shunts, yielding lower morbidity and mortality.

Outcomes of Infants Undergoing Modified Blalock-Taussig Shunt Procedures in Oman: A retrospective study

Objectives

A modified Blalock-Taussig (mBT) shunt procedure is a common palliative surgery used to treat infants and children with cyanotic congenital heart disease (CCHD). This study aimed to report the outcomes of infants and children undergoing mBT shunt procedures in Oman. In addition, risk factors associated with early mortality, inter-stage mortality and reintervention were assessed.

Methods

This retrospective cohort study was conducted from January 2016 to December 2018 at the National Heart Centre, Muscat, Oman. All paediatric patients with CCHD undergoing mBT shunt procedures as a primary palliative procedure during this period were included. Data were retrieved from electronic hospital records. Kaplan-Meier survival curves were used to describe overall survival.

Results

A total of 50 infants and children were included in this study. The in-hospital mortality and interstage mortality rates were 10% and 6.7%, respectively. Preoperative mechanical ventilation (odds ratio [OR] = 3.00, 95% confidence interval [CI]: 1.98–4.76; P = 0.007) and cardiopulmonary bypass (OR = 4.09, 95% CI: 2.44–6.85; P = 0.002) were significant risk factors for early mortality. In-hospital and interval surgical reintervention rates were 12% and 13.3%, respectively. Following the primary shunt procedure, the median time to second-stage surgery was 15.5 months (range: 5.0–34.0 months).

Conclusion

The findings of this study support those reported in international research regarding the risks associated with mBT shunt surgeries. In particular, preoperative mechanical ventilation and cardiopulmonary bypass were significant risk factors for early mortality.

Contemporary patterns of the management of truncus arteriosus (primary versus staged repair): outcomes from the Japanese National Cardiovascular Database

OBJECTIVES

Although primary repair in early infancy has for decades been the prevalent strategy for management of truncus arteriosus (TA), recent concerns about the levels of morbidity and mortality have led to consideration of a staged surgical approach. Our goal was to describe recent patterns of management, to characterize patients who underwent primary or staged repair and to evaluate risk factors associated with operative mortality in a contemporary multicentre cohort.

METHODS

In the Japanese Cardiovascular Surgery Database, we identified all cases of TA undergoing an initial surgical procedure from 2008 to 2018. Operative mortality was defined as death within 30 days of an operation or in-hospital death regardless of the length of hospital stay. The hospital volume was defined by the average volume of TA repairs per year.

RESULTS

The total number of patients undergoing initial surgery for TA was 286. Sixty-eight (24%, 68/286) underwent primary repair (primary repair group). The remaining 218 (76%, 218/286) underwent initial bilateral pulmonary artery banding as part of a planned staged approach (staged repair group). One hundred sixty-two patients out of 218 initially banded patients underwent the repair of TA during this study period. Concomitant diagnoses in the entire cohort included interrupted aortic arch repair in 36 patients and truncal valve regurgitation in 32. No centres handling an average of ≥2 truncus cases/year of the repair of TA were identified in this cohort. A total of 30% (85/286) of the cases were performed at centres that handled an average of ≥1 and <2 cases/year. The remaining 70% were at centres with <1 case/year. Overall, 37 patients (12.9%; 37/286) died. The operative mortality rates in the primary and staged repair groups were similar: that for the primary repair group was 16.2% (11/68) versus 11.9% for the staged repair group (26/218; P = 0.41). With multivariable logistic regression analysis, the factors most strongly associated with operative mortality were preoperative heart failure requiring catecholamine support (odds ratio, 4.18; 95% confidence interval 1.96-8.96) and the repeat bilateral pulmonary artery banding (odds ratio, 3.89; 95% confidence interval 1.08-14.07).

CONCLUSIONS

The staged repair of TA has emerged as the preferred option for surgical timing at most of the centres participating in the Japanese Cardiovascular Surgery Database. The management outcomes of the patients with TA were favourable, even for the patients at low-volume centres.

Are early palliative procedures providing an adequate long-term benefit in young cyanotic infants from developing countries, despite advances in surgery and interventions?

OBJECTIVES

Ductal stents, right ventricular outflow tract stents, and aortopulmonary shunts are used to palliate newborns and infants with reduced pulmonary blood flow. Current long-term outcomes of these palliations from resource-restricted countries are unknown.

METHODS

This single-centre, retrospective, observational study analysed the technical success, immediate and late mortality, re-interventions, and length of palliation in infants ≤5 kg who underwent aortopulmonary shunts, ductal, and pulmonary outflow stents. Patients were grouped by their anatomy.

RESULTS

There were 69 infants who underwent one of the palliations. Technical success was 90% for aortopulmonary shunts (n = 10), 91% for pulmonary outflow stents (n = 11) and 100% for ductal stents (n = 48). Early mortality within 30 days in 12/69 patients was observed in 20% after shunts, 9% after pulmonary outflow stents, and 19% after ductal stents. Late mortality in 11 patients was seen in 20% after shunts, 18% after outflow stents, and 15% after ductal stents. Seven patients needed re-interventions; two following shunts, one following outflow stent, and four following ductal stents for hypoxia. Among the anatomical groups, 10/12 patients with pulmonary atresia, intact ventricular septum survived after valvotomy and ductal stenting. Survival to Glenn shunt after ductal stent for pulmonary atresia, intact ventricular septum and diminutive right ventricle was very low in two out of eight patients, but very good (100%) for other univentricular hearts. Among 35 patients with biventricular lesions, 22 survived to the next stage.

CONCLUSIONS

Cyanotic infants, despite undergoing technically successful palliation had a high inter-stage mortality irrespective of the type of palliation. Duct stenting in univentricular hearts and in pulmonary atresia with an intact ventricular septum and adequate sized right ventricle tended to have low mortality and better long-term outcome. Completion of biventricular repair after palliation was achieved only in 63% of patients, reflecting unique challenges in developing countries despite advances in intensive care and interventions.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

National Variation in Congenital Heart Surgery Outcomes

BACKGROUND

Optimal strategies to improve national congenital heart surgery outcomes and reduce variability across hospitals remain unclear. Many policy and quality improvement efforts have focused primarily on higher-risk patients and mortality alone. Improving our understanding of both morbidity and mortality and current variation across the spectrum of complexity would better inform future efforts.

METHODS

Hospitals participating in the Society of Thoracic Surgeons Congenital Heart Surgery Database (2014-2017) were included. Case mix-adjusted operative mortality, major complications, and postoperative length of stay were evaluated using Bayesian models. Hospital variation was quantified by the interdecile ratio (IDR, upper versus lower 10%) and 95% credible intervals (CrIs). Stratified analyses were performed by risk group (Society of Thoracic Surgeons-European Association for Cardiothoracic Surgery [STAT] category) and simulations evaluated the potential impact of reductions in variation.

RESULTS

A total of 102 hospitals (n=84 407) were included, representing ≈85% of US congenital heart programs. STAT category 1 to 3 (lower risk) operations comprised 74% of cases. All outcomes varied significantly across hospitals: adjusted mortality by 3-fold (upper versus lower decile 5.0% versus 1.6%, IDR 3.1 [95% CrI 2.5-3.7]), mean length of stay by 1.8-fold (19.2 versus 10.5 days, IDR 1.8 [95% CrI 1.8-1.9]), and major complications by >3-fold (23.5% versus 7.0%, IDR 3.4 [95% CrI 3.0-3.8]). The degree of variation was similar or greater for low- versus high-risk cases across outcomes, eg, ≈3-fold mortality variation across hospitals for STAT 1 to 3 (IDR 3.0 [95% CrI 2.1-4.2]) and STAT 4 or 5 (IDR 3.1 [95% CrI 2.4-3.9]) cases. High-volume hospitals had less variability across outcomes and risk categories. Simulations suggested potential reductions in deaths (n=282), major complications (n=1539), and length of stay (101 183 days) over the 4-year study period if all hospitals were to perform at the current median or better, with 37% to 60% of the improvement related to the STAT 1 to 3 (lower risk) group across outcomes.

CONCLUSIONS

We demonstrate significant hospital variation in morbidity and mortality after congenital heart surgery. Contrary to traditional thinking, a substantial portion of potential improvements that could be realized on a national scale were related to variability among lower-risk cases. These findings suggest modifications to our current approaches to optimize care and outcomes in this population are needed.

Outcomes of systemic-to-pulmonary artery shunt for single ventricular heart with extracardiac total anomalous pulmonary venous connection

OBJECTIVES

A few studies have described the outcomes of systemic-to-pulmonary artery shunt (SPS) for functional single ventricular heart with extracardiac total anomalous pulmonary venous connection (TAPVC). This study aimed to examine the outcomes of SPS with extracardiac TAPVC and identify the predictors of mortality before bidirectional Glenn operation (BDG).

METHODS

Medical records of 41 children with single ventricular heart and extracardiac TAPVC who underwent SPS between 1998 and 2019 were reviewed retrospectively. The median age and body weight at SPS were 36 days and 3.4 kg, respectively. Surgical outcomes and predictors of mortality were investigated.

RESULTS

Four operative deaths (10%) and 10 late deaths (27%) occurred before BDG. Of all the children, 19 underwent BDG at a median of 10 months since SPS and eight are waiting for BDG. In the multivariate analysis, preoperative pulmonary venous obstruction (p = 0.01) at initial surgery was most predictive of death before BDG. Patients who underwent simultaneous SPS and TAPVC repair were younger, had high preoperative rate of pulmonary venous obstruction, and more deaths before BDG.

CONCLUSIONS

Survival outcomes of SPS for SVH with extracardiac TAPVC were improved as a whole due to the increase in knowledge and technique of management SPS. However, the patients who have preoperative pulmonary venous obstruction (PVO) and need SPS and TAPVC repair concomitantly in the early postnatal period have poor outcomes and still challenging. In such a case, staged TAPVC repair and SPS may be beneficial.

Platelet Inhibition With IV Glycoprotein IIb/IIIa Inhibitor to Prevent Thrombosis in Pediatric Patients Undergoing Aortopulmonary Shunting

OBJECTIVES

Shunt thrombosis, a potential complication of aortopulmonary shunting, is associated with high mortality. Commonly used oral antiplatelet drugs such as aspirin demonstrate variable absorption and inconsistent antiplatelet effect in critically ill patients early after surgery. IV glycoprotein IIb/IIIa inhibitors are antiplatelet agents with rapid and reproducible effect that may be beneficial as a bridge to oral therapy.

DESIGN

Retrospective review of pediatric patients undergoing treatment with IV tirofiban. Discarded blood samples were used to determine pharmacokinetic parameters.

SETTING

Pediatric cardiac ICU at a single institution.

PATIENTS

Fifty-two pediatric patients (< 18 yr) undergoing surgical aortopulmonary shunt procedure who received tirofiban infusion as a bridge to oral aspirin.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Primary outcome measures were shunt thrombosis and bleeding events, whereas secondary outcomes included measurement of platelet inhibition by thromboelastography with platelet mapping and pharmacokinetic analysis (performed in a subset of 15 patients). Shunt thrombosis occurred in two of 52 patients (3.9%) after prophylaxis treatment with tirofiban; both thrombosis events occurred after discontinuation of the drug. One patient (1.9%) experienced bleeding complication during the infusion. A tirofiban bolus of 10 µg/kg and infusion of 0.15 µg/kg/min resulted in significantly increased platelet inhibition via adenosine diphosphate pathway (median 66% [43-96] pre-tirofiban compared with 97% [92-99%] at 2 hr; p < 0.05). Half-life of tirofiban in plasma was 142 ± 1.5 minutes, and the average steady-state concentration was 112 ± 62 ng/mL. Age and serum creatinine were significant covariates associated with systemic clearance. Dosing simulations were generated based upon one compartment model.

CONCLUSIONS

IV glycoprotein IIb/IIIa inhibitor as a bridge to oral antiplatelet therapy is safe in pediatric patients after aortopulmonary shunting. Dosing considerations should include both age and renal function. Randomized trials are warranted to establish efficacy compared with current anticoagulation practices.

Surgical Options for Pulmonary Atresia with Ventricular Septal Defect in Neonates and Young Infants

BACKGROUND

The optimal surgical strategy for pulmonary atresia with ventricular septal defect (PA/VSD) in neonates and young infants is controversial. Staged repair may be associated with a higher risk of inter-stage mortality, while primary repair may lead to frequent post-repair re-interventions.

METHODS

From 2004 to 2017, 65 patients with PA/VSD who underwent surgical intervention before 90 days of age were identified and enrolled in this retrospective study. The cohort was divided into two groups: group-SR, who underwent initial palliation with staged repair (n = 50), and group-PR who underwent primary repair (n = 15).

RESULTS

There were three post-palliation in-hospital mortalities, four inter-stage mortalities, and one post-repair in-hospital mortality in group-SR. In group-PR, there was one in-hospital death and one late death. Five-year survival rates were comparable between the two groups (group-SR: 83.6%; group-PR: 86.7%; p = 0.754). During the median follow-up duration of 44.7 months (Inter-quartile range, 19-109 months), 40 post-repair re-interventions (22 in group-SR, 18 in group-PR) were performed in 26 patients (18 in group-SR, 8 in group-PR). On Cox proportional hazards model, primary repair was identified as the only risk factor for decreased time to death/1st post-repair re-intervention (Hazard ratio (HR): 2.3, p = 0.049) and death/2nd post-repair re-intervention (HR 2.91, p = 0.033).

CONCLUSIONS

A staged repair strategy, compared with primary repair, was associated with comparable overall survival with less frequent re-interventions after repair in young infants with PA/VSD. Lowering the inter-stage mortality after initial palliation by vigilant outpatient care and aggressive home monitoring may be the key to better surgical outcomes in this subset. Surgical outcomes of PA with VSD according to the surgical strategies. Patient 1 (birth weight: 2.7 kg) underwent primary Rastelli-type repair at post-natal day # 50 (body weight: 3.8 kg) using Contegra® 12 mm. The postoperative course was rocky, with long ventilatory support (10 days), ICU stay (14 days), and hospital stay (20 days). Cardiac CT scan at 9 months post-repair showed severe branch pulmonary artery stenosis, which necessitated LPA stenting at 12 months post-repair and RV-PA conduit replacement with extensive pulmonary artery reconstruction at 25 months post-repair. Patient 2 (birth weight: 2.5 kg) underwent RMBT at post-natal day #30 (body weight: 3.4 kg) using 4 mm PTFE vascular graft and staged Rastelli-type repair at post-natal 11 months using a hand-made Gore-Tex valved conduit (14 mm). No post-repair re-intervention has been performed. Cardiac CT scan at 90 months post-repair showed no branch pulmonary artery stenosis.CT computed tomography, ICU intensive care unit, LPA left pulmonary artery, PA pulmonary atresia, PTFE polytetrafluoroethylene, RMBT right modified Blalock-Taussig shunt, RV-PA right ventricle to pulmonary artery, VSD ventricular septal defect.