A modified intraventricular balloon method for functional assessment of hearts from donation after circulatory death.

Objective: Functional assessment of hearts during ex-vivo heart perfusion is not well-established. Conventional intraventricular balloon methods for large animals sacrifice the mitral valve. This study assessed the effectiveness of the modified intraventricular balloon method in comparison with other modalities used during working mode in juvenile pigs. Methods: Following asphyxia circulatory arrest, hearts were ischemic for 15 minutes and then reperfused on an ex-vivo device for 2 hours before switching to working mode. Left ventricular pressure was continuously measured during reperfusion by a saline-filled balloon fixated in the left atrium. Spearman Correlation Coefficients with linear regression lines with confidence intervals were analyzed. Results: Maximum dp/dt at 90 minutes of reperfusion and minimum dp/dt at 60 minutes of reperfusion showed a moderate positive correlation to that in working mode, respectively (Rs = 0.61, P = .04 and Rs = 0.60, P = .04). At 60 minutes of reperfusion, minimum dp/dt showed moderate positive correlation to tau (Rs = 0.52, P = .08). Myocardial oxygen consumption during reperfusion consistently decreased at least 30% compared to working mode (at 90 minutes as the highest during reperfusion, 3.3 ± 0.8; in working mode, 5.6 ± 1.4, mLO2/min/100 g, P < .001). Conclusions: Functional parameters of contractility and relaxation measured during reperfusion by the modified balloon method showed significant correlations to respective parameters in working mode. This mitral valve sparing technique can be used to predict viability and ventricular function in the early phase of ex-vivo heart perfusion without loading the heart during working mode.

Longitudinal Evaluation of Congenital Cardiovascular Surgical Performance and Skills Retention Using Silicone-Molded Heart Models.

Objective: Hands-on surgical training (HOST) for congenital heart surgery (CHS), utilizing silicone-molded models created from 3D-printing of patients' imaging data, was shown to improve surgical skills. However, the impact of repetition and frequency of repetition in retaining skills has not been previously investigated. We aimed to longitudinally evaluate the outcome for HOST on two example procedures of different technical difficulties with repeated attempts over a 15-week period. Methods: Five CHS trainees were prospectively recruited. Repair of coarctation of the aorta (CoA) and arterial switch operation (ASO) were selected as example procedures of relatively low and high technical difficulty. Procedural time and technical performance (using procedure-specific assessment tools by the participant, a peer-reviewer, and the proctor) were measured. Results: Coarctation repair performance scores improved after the first repetition but remained unchanged at the follow-up session. Likewise, CoA procedural time showed an early reduction but then remained stable (mean [standard deviation]: 29[14] vs 25[15] vs 23[9] min at 0, 1, and 4 weeks). Conversely, ASO performance scores improved during the first repetitions, but decreased after a longer time delay (>9 weeks). Arterial switch operation procedural time showed modest improvements across simulations but significantly reduced from the first to the last attempt: 119[20] versus 106[28] min at 0 and 15 weeks, P = .049. Conclusions: Complex procedures require multiple HOST repetitions, without excessive time delay to maintain long-term skills improvement. Conversely, a single session may be planned for simple procedures to achieve satisfactory medium-term results. Importantly, a consistent reduction in procedural times was recorded, supporting increased surgical efficiency.

Early outcomes of moderate-to-high-risk pediatric congenital cardiac surgery and predictors of extracorporeal circulatory life support requirement.

Background: Cardiopulmonary failure refractory to medical management after moderate-to-high-risk congenital cardiac surgery may necessitate mechanical support with veno-arterial extracorporeal membrane oxygenation (ECMO). On the extreme, ECMO can also be initiated in the setting of cardiac arrest (extracorporeal cardiopulmonary resuscitation, ECPR) unresponsive to conventional resuscitative measures. Methods: This was a single-center retrospective cohort study of patients (n = 510) aged <3 years old who underwent cardiac surgery with cardiopulmonary bypass with a RACHS-1 score ≥3 between 2011 and 2014. Perioperative factors were reviewed to identify predictors of ECMO initiation and mortality in the operating room (OR) and the intensive care unit (ICU). Results: A total of 510 patients with a mean surgical age of 10.0 ± 13.4 months were included. Among them, 21 (4%) patients received postoperative ECMO-12 were initiated in the OR and 9 in the ICU. ECMO cannulation was associated with cardiopulmonary bypass duration, aortopulmonary shunt, residual severe mitral regurgitation, vaso-inotropic score, and postprocedural lactate (p < 0.001). Of the 32 (6%) total deaths, 7 (22%) were ECMO patients-4 were elective OR cannulations and 3 were ICU ECPR. Prematurity [hazard ratio (HR): 2.61, p < 0.01), Norwood or Damus-Kaye-Stansel procedure (HR: 4.29, p < 0.001), postoperative left ventricular dysfunction (HR: 5.10, p = 0.01), residual severe tricuspid regurgitation (HR: 6.06, p < 0.001), and postoperative ECMO (ECPR: HR: 15.42, p < 0.001 vs. elective: HR: 5.26, p = 0.01) were associated with mortality. The two patients who were electively cannulated in the ICU survived. Discussion: Although uncommon, postoperative ECMO in children after congenital cardiac surgery is associated with high mortality, especially in cases of ECPR. Patients with long cardiopulmonary bypass time, residual cardiac lesions, or increased vaso-inotropic requirement are at higher risk of receiving ECMO. Pre-emptive or early ECMO initiation before deterioration into cardiac arrest may improve survival.

Impact of Hemoglobin Level in Ex Vivo Heart Perfusion on Donation After Circulatory Death Hearts: A Juvenile Porcine Experimental Model.

BACKGROUND: Ex vivo heart perfusion (EVHP) of donation after circulatory death (DCD) hearts has become an effective strategy in adults; however, the small circulating volume in pediatrics poses the challenge of a low-hemoglobin (Hb) perfusate. We aimed to determine the impact of perfusate Hb levels during EVHP on DCD hearts using a juvenile porcine model. METHODS: Sixteen DCD piglet hearts (11-14 kg) were reperfused for 4 h in unloaded mode followed by working mode. Metabolism, cardiac function, and cell damage were compared between the low-Hb (Hb, 5.0-5.9 g/dL; n = 8) and control (Hb, 7.5-8.4 g/dL; n = 8) groups. Between-group differences were evaluated using 2-sample t-tests or Fisher's Exact tests. RESULTS: During unloaded mode, the low-Hb group showed lower myocardial oxygen consumption (P < 0.001), a higher arterial lactate level (P = 0.001), and worse systolic ventricular function (P < 0.001). During working mode, the low-Hb group had a lower cardiac output (mean, 71% versus 106% of normal cardiac output, P = 0.010) and a higher arterial lactate level (P = 0.031). Adjusted cardiac troponin-I (P = 0.112) did not differ between the groups. Morphological myocyte injury in the left ventricle was more severe in the low-Hb group (P = 0.028). CONCLUSIONS: Low-Hb perfusate with inadequate oxygen delivery induced anaerobic metabolism, resulting in suboptimal DCD heart recovery and declined cardiac function. Arranging an optimal perfusate is crucial to organ protection, and further endeavors to refine the priming volume of EVHP or the transfusion strategy are required.

Coronary artery lesions are associated with adverse cardiac events in children undergoing supravalvular aortic stenosis repair.

OBJECTIVES: The aim of this study was to identify the prevalence and anatomic characteristics of coronary artery lesions and their associated postoperative risk in patients undergoing supravalvular aortic stenosis repair. METHODS: The association between structural risk factors, postoperative ST-segment changes, and major adverse cardiac events was explored using logistic regression and the Fisher's exact test. RESULTS: In 51 consecutive patients with supravalvular aortic stenosis treated between 2000 and 2017, a total of 48 coronary lesions were identified in 27 patients (53%). Prominent ostial ridge (type I) was the most common coronary lesion, followed by small ostium with (IIIb) or without (IIIa) diffuse long-segment coronary narrowing, and adhesion of the coronary cusp (type II). There were 54 concomitant coronary procedures, including 43 primary corrections and 11 revisions. Thirty-three patients underwent supravalvular aortic stenosis repair with a bifurcated patch, of which 13 (39.4%) had right coronary artery distortion/kinking requiring patch plication (n = 8) and reimplantation (n = 5). Postoperative major adverse cardiac events (MACE) occurred in 9 patients (17.6%), including 3 deaths, 4 needing mechanical circulatory support, and 6 experiencing ventricular arrhythmias. Twenty-two patients (43.1%) had postoperative ST-segment changes, including 13 early changes that resolved within 24 h and 9 persistent changes lasting >24 h. Patients with type III lesions were associated with postoperative persistent ST-segment change (P = 0.04) and these lesions independently predicted postoperative MACE (P = 0.02). Patients with pre-existing coronary lesions were at elevated risk of right coronary artery distortion/kinking (P = 0.045). CONCLUSIONS: The prevalence of ST-segment changes and MACE is high in patients undergoing supravalvular aortic stenosis repair. The preoperative presence of complex coronary lesions is the most important predictor for postoperative major adverse cardiac events.

A Pediatric Primary Cardiac Spindle Cell Neoplasm With a Rare PDGFRA::USP8 Gene Fusion: A Case Report.

We report a case of a primary cardiac spindle cell neoplasm with concerning histological features and a rare PDGFRA::USP8 gene fusion in a 3 year old boy. The patient presented with a large cardiac mass predominantly in the right ventricle, originating from the ventricular septum. The mass was resected with grossly negative margins. Pathology revealed an unclassified spindle cell neoplasm with a PDGFRA::USP8 gene fusion. This gene fusion has only been previously reported twice in the medical literature, one in a pediatric cardiac sarcoma and the other in an abdominal soft tissue tumor in an adult woman. The patient is alive and well with no evidence of recurrence 11 months after excision.

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.

Mechanical atrioventricular valve replacement in patients with single ventricle palliation.

OBJECTIVES: Atrioventricular valve (AVV) replacements in patients with single-ventricle circulations pose significant surgical risks and are associated with high morbidity and mortality. METHODS: From 1997 to 2021, 16 consecutive patients with functionally single-ventricle physiology underwent mechanical AVV replacement. Primary outcome was transplant-free survival. Secondary outcomes included major postoperative morbidity. RESULTS: The median age of AVV replacement was 2 years old (interquartile range 0.6-3.8 years). All AVV replacements were performed with a St. Jude Medical mechanical valve, median 24 mm (range, 19-31mm). Extracorporeal membrane oxygenation (ECMO) was required in 4 patients. Operative mortality was 38% (6/16). There were 2 late deaths and 3 transplants. Transplant-free survival was 50% at 1 year, 37.5% at 5 years, and 22% at 10 years. Transplant-free survival was higher for patients with preserved ventricular function (P = 0.01). Difference in transplant-free survival at 1 year was 75% vs 25%, at 5 years was 62.5% vs 12.5% and at 10 years was 57% vs 0%. Three (19%) patients had complete heart block requiring permanent pacemaker insertion. 6 of 13 patients (46%) patients reached Fontan completion (3 patients operated at/after Fontan). Significant bleeding events occurred in 8 patients (50%) with 3 patients suffering major cerebrovascular accidents. There were 6 events of valve thrombosis in 5 patients, resulting in 2 deaths and 2 heart transplants. CONCLUSIONS: Mechanical valve replacement carries significant morbidity and mortality risk. While it successfully salvages about half of patients with preserved ventricular function, careful consideration of alternative options should be made before embarking upon mechanical valve replacement.

Left atrial appendage aneurysm in pediatrics: Case study and literature review.

Left atrial appendage aneurysm (LAAA) is a rare cardiac pathology that is often identified in adulthood. There are a myriad of presentations related to atrial appendage enlargement, but most are asymptomatic. Pediatric cases of LAAA are extremely rare. We report a case of an incidental giant LAAA found in a healthy 6-year-old boy. He was successfully treated with surgical resection. A review of the literature shows that the presentation of LAAA in pediatrics likely involves cardiac or respiratory symptoms but can also be incidental findings. Similar to adults, diagnosis requires cardiac imaging, with echocardiography being the mainstay. Surgical intervention is indicated in symptomatic and most asymptomatic patients to prevent complications. More research is warranted into the optimal timing of surgery and alternative surgical approaches for complex cases.

Reintervention Before Bidirectional Cavopulmonary Shunt and Intermediate Outcomes in Children with Single Ventricle Who Underwent Main Pulmonary Artery Banding.

Unplanned reinterventions following pulmonary artery banding (PAB) in single ventricle patients are common before stage 2 palliation (S2P) but associated risk factors are unknown. We hypothesized that reintervention is more common when PAB is placed at younger age and with a looser band, reflected by lower PAB pressure gradient. Retrospective single center study of single ventricle patients undergoing PAB between Jan 2000 and Dec 2020. The association with reintervention and successful S2P was modeled using exploratory cause-specific hazard regression. A multivariable model was developed adjusting for clinical and statistically relevant predictors. The cumulative proportion of patients undergoing reintervention were summarized using a competing risk model. 77 patients underwent PAB at median (IQR) 47 (24-66) days and 3.73 (3.2-4.5) kg. Within18 months of PAB, 60 (78%) reached S2P, 9 (12%) died, 1 (1%) transplanted and 7 (9%) were alive without S2P. Within 18 months of PAB 10 (13%) patients underwent reintervention related to pulmonary blood flow modification: PAB adjustment (n = 6) and conversion to Damus-Kaye-Stansel/Blalock-Taussig-Thomas shunt (n = 4). 6/10 (60%) reached S2P following reintervention. A trend toward higher intervention in patients with a genetic syndrome (p-0.06) and weight < 3 kg (p-0.057) at time of PAB was noted. Only genetic syndrome was a risk factor associated with poor outcome (p-0.025). PAB has a reasonable outcome in SV patients with unobstructed systemic and pulmonary blood flow, but with a high reintervention rate. Only a quarter of patients with genetic syndromes reach S2P and further study is required to explore the benefits from an alternative palliative strategy.

Epinephrine Dosing Use During Extracorporeal Cardiopulmonary Resuscitation: Single-Center Retrospective Cohort.

OBJECTIVES: During pediatric cardiac arrest, contemporary guidelines recommend dosing epinephrine at regular intervals, including in patients requiring extracorporeal membrane oxygenation (ECMO). The impact of epinephrine-induced vasoconstriction on systemic afterload and venoarterial ECMO support is not well-defined. DESIGN: Nested retrospective observational study within a single center. The primary exposure was time from last dose of epinephrine to initiation of ECMO flow; secondary exposures included cumulative epinephrine dose and arrest time. Systemic afterload was assessed by mean arterial pressure and use of systemic vasodilator therapy; ECMO pump flow and Vasoactive-Inotrope Score (VIS) were used as measures of ECMO support. Clearance of lactate was followed post-cannulation as a marker of systemic perfusion. SETTING: PICU and cardiac ICU in a quaternary-care center. PATIENTS: Patients 0-18 years old who required ECMO cannulation during resuscitation over the 6 years, 2014-2020. Patients were excluded if ECMO was initiated before cardiac arrest or if the resuscitation record was incomplete. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 92 events in 87 patients, with 69 events having complete data for analysis. The median (interquartile range) of total epinephrine dosing was 65 mcg/kg (37-101 mcg/kg), with the last dose given 6 minutes (2-16 min) before the initiation of ECMO flows. Shorter interval between last epinephrine dose and ECMO initiation was associated with increased use of vasodilators within 6 hours of ECMO ( p = 0.05), but not with mean arterial pressure after 1 hour of support (estimate, -0.34; p = 0.06). No other associations were identified between epinephrine delivery and mean arterial blood pressure, vasodilator use, pump speed, VIS, or lactate clearance. CONCLUSIONS: There is limited evidence to support the idea that regular dosing of epinephrine during cardiac arrest is associated with increased in afterload after ECMO cannulation. Additional studies are needed to validate findings against ECMO flows and clinically relevant outcomes.

Heart transplantation in neonatal Marfan syndrome: Saving life in a rare and fatal condition.

BACKGROUND: Neonatal Marfan syndrome is a rare disease with mortality in the first year of life reported as high as 95% predominantly due to progressive heart failure from valvar regurgitation and cardiomyopathy. Multisystem involvement and uncertain prognosis have historically precluded transplant candidacy, and current management options are of limited success. CASE REPORT: We present a baby girl with a postnatal diagnosis of neonatal Marfan syndrome who at 1 year of age underwent mitral valve and tricuspid valve repair with postoperative profound left ventricular and moderate right ventricular dysfunction necessitating biventricular assist device (BiVAD) support and subsequent heart transplant. A number of noncardiac issues persisted in our patient; however, she enjoyed a good quality of life for the initial 3 years posttransplant. Unfortunately, she subsequently developed rapidly progressive coronary allograft vasculopathy (CAV) with progressive deterioration in function and cardiac arrest. CONCLUSION: To our best knowledge, this is only the second case of neonatal Marfan syndrome to undergo heart transplant reported in the literature and the first with BiVAD support as a bridge to candidacy. This is also the first case of neonatal Marfan syndrome associated with intragenic duplication. This case though demonstrating that earlier listing, ventricular assist device (VAD) support and even primary transplant as treatment in neonatal Marfan syndrome should all be considered viable options but also portends a cautionary tale given the spectrum of comorbidities in this rare and severe disorder.

Hybrid palliation versus nonhybrid management for a multi-institutional cohort of infants with critical left heart obstruction.

OBJECTIVE: To compare patient characteristics and overall survival for infants with critical left heart obstruction after hybrid palliation (bilateral pulmonary artery banding with or without ductal stenting) versus nonhybrid management (eg, Norwood, primary transplantation, biventricular repair, or transcatheter/surgical aortic valvotomy). METHODS: From 2005 to 2019, 1045 infants in the Congenital Heart Surgeons' Society critical left heart obstruction cohort underwent interventions across 28 institutions. Using a balancing score propensity analysis, 214 infants who underwent hybrid palliation and 831 infants who underwent nonhybrid management were proportionately matched regarding variables significantly associated with mortality and variables noted to significantly differ between groups. Overall survival between the 2 groups was adjusted by applying balancing scores to nonparametric estimates. RESULTS: Compared with the nonhybrid management group, infants who underwent hybrid palliation had lower birth weight, smaller gestational age, and higher prevalence of in-utero interventions, noncardiac comorbidities, preoperative mechanical ventilation, absent interatrial communication, and moderate or severe mitral valve stenosis (all P values < .03). Unadjusted 12-year survival after hybrid palliation and nonhybrid management, was 55% versus 69%, respectively. After matching, 12-year survival after hybrid palliation versus nonhybrid management was 58% versus 63%, respectively (P = .37). Among matched infants born weighing <2.5 kg, 2-year survival after hybrid palliation versus nonhybrid management was 37% versus 51%, respectively (P = .22). CONCLUSIONS: Infants born with critical left heart obstruction who undergo hybrid palliation have more high-risk characteristics and anatomy versus infants who undergo nonhybrid management. Nonetheless, after adjustment, there was no significant difference in 12-year survival after hybrid palliation versus nonhybrid management. Mortality remains high, and hybrid palliation confers no survival advantage, even for lower-birth-weight infants.

Modified central shunt in pulmonary atresia with diminutive pulmonary arteries.

The commonly used central shunt (i.e. direct connection of the divided main pulmonary artery to the ascending aorta) to facilitate the growth of the diminutive branch pulmonary artery in patients with pulmonary atresia with major aortopulmonary collateral arteries can cause main pulmonary artery distortion, and subsequent disproportional branch pulmonary artery flow and growth. This report describes a novel technique of shunt construction to minimize pulmonary artery torque and tension by using a modified central shunt constructed from autologous pericardium that is anastomosed in an end-to-side fashion to the lateral aspect of the ascending aorta. This shunt will serve as an intermediary conduit to facilitate the main pulmonary artery anastomosis while minimizing torque and tension on the main pulmonary artery. The tension-free connection between the main pulmonary artery and the aorta enabled by the modified central shunt supports proportional pulmonary artery flow and growth in patients with pulmonary atresia, ventricular septal defect, or multiple aortopulmonary collateral arteries and concomitant diminutive native pulmonary arteries.

Pitfalls and Possibilities of Ventricular Assist Device Support in Congenitally Corrected Transposition of the Great Arteries in Children.

Congenitally corrected transposition of the great arteries (ccTGAs) represents a complex form of congenital heart disease that is associated with several cardiac complications. Herein is a case series of three children with ccTGA and ventricular assist device (VAD) inserted for systemic right ventricle failure at a single institution. All patients remained hemodynamically stable postimplant and were successfully discharged from the intensive care unit to undergo postoperative rehabilitation. All three patients received an orthotopic heart transplant with uneventful posttransplant courses. This case series provides insight into the medical management and technical feasibility of VAD support in children with ccTGA with end-stage heart failure.

Surgical management of acute life-threatening events affecting esophageal atresia and/or tracheoesophageal fistula patients.

BACKGROUND: Following surgical correction, many patients with esophageal atresia with or without tracheoesophageal fistula (EA/TEF) present to the emergency department (ED) with acute airway complications. We sought to determine the incidence and risk factors for severe acute life-threatening events (ALTEs) in pediatric patients with repaired congenital EA/TEF and the outcomes of operative interventions. METHODS: A retrospective cohort chart review was performed on patients with EA/TEF with surgical repair and follow-up at a single centre from 2000 to 2018. Primary outcomes included 5-year ED visits and/or hospitalizations for ALTEs. Demographic, operative, and outcome data were collected. Chi-square tests and univariate analyses were performed. RESULTS: In total, 266 EA/TEF patients met inclusion criteria. Of these, 59 (22.2%) had experienced ALTEs. Patients with low birth weight, low gestational age, documented tracheomalacia, and clinically significant esophageal strictures were more likely to experience ALTEs (p < 0.05). ALTEs occurred prior to 1 year of age in 76.3% (45/59) of patients with a median age at presentation of 8 months (range 0-51 months). Recurrence of ALTEs after esophageal dilatation was 45.5% (10/22), mostly due to stricture recurrence. Patients experiencing ALTEs received anti-reflux procedures (8/59, 13.6%), airway pexy procedures (7/59, 11.9%), or both (5/59, 8.5%) within a median age of 6 months of life. The resolution and recurrence of ALTEs after operative interventions are described. CONCLUSION: Significant respiratory morbidity is common among patients with EA/TEF. Understanding the multifactorial etiology and operative management of ALTEs have an important role in their resolution. TYPE OF STUDY: Original Research, Clinical Research. LEVEL OF EVIDENCE: Level III Retrospective Comparative Study.

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.

Osteosarcoma emboli presenting as chronic thromboembolic pulmonary hypertension in a child.

A 13-year-old girl presented with hypoxemia during adjuvant chemotherapy for an osteosarcoma of the left distal femur. She underwent an amputation complicated by a post-operative pulmonary embolism (PE). Three months post-operatively, she was admitted to hospital with severe hypoxemia and diagnosed with pulmonary hypertension on echocardiogram in the context of extensive bilateral PE on computed tomography. She was planned for elective pulmonary thromboendarterectomy, but rapidly deteriorated requiring emergent surgery. At the time of surgery, she was found to have extensive tumor emboli throughout both pulmonary arteries. She recovered well post-operatively but died 2 months later from progressive disease.

Cardioprotective Actions of a Glucagon-like Peptide-1 Receptor Agonist on Hearts Donated After Circulatory Death.

Background Heart transplantation with a donation after circulatory death (DCD) heart is complicated by substantial organ ischemia and ischemia-reperfusion injury. Exenatide, a glucagon-like peptide-1 receptor agonist, manifests protection against cardiac ischemia-reperfusion injury in other settings. Here we evaluate the effects of exenatide on DCD hearts in juvenile pigs. Methods and Results DCD hearts with 15-minutes of global warm ischemia after circulatory arrest were reperfused ex vivo and switched to working mode. Treatment with concentration 5-nmol exenatide was given during reperfusion. DCD hearts treated with exenatide showed higher myocardial oxygen consumption (exenatide [n=7] versus controls [n=7], over 60-120 minutes of reperfusion, P<0.001) and lower cardiac troponin-I release (27.94±11.17 versus 42.25±11.80 mmol/L, P=0.04) during reperfusion compared with controls. In working mode, exenatide-treated hearts showed better diastolic function (dp/dt min: -3644±620 versus -2193±610 mm Hg/s, P<0.001; Tau: 15.62±1.78 versus 24.59±7.35 milliseconds, P=0.02; lateral e' velocity: 11.27 ± 1.46 versus 7.19±2.96, P=0.01), as well as lower venous lactate levels (3.17±0.75 versus 5.17±1.44 mmol/L, P=0.01) compared with controls. Higher levels of activated endothelial nitric oxide synthase (phosphorylated to total endothelial nitric oxide synthase levels: 2.71±1.16 versus 1.37±0.35, P=0.02) with less histological evidence of endothelial damage (von Willebrand factor expression: 0.024±0.007 versus 0.331±0.302, pixel/µm, P=0.04) was also observed with exenatide treatment versus controls. Conclusions Acute treatment of DCD hearts with exenatide limits myocardial and endothelial injury and improves donor cardiac function.