Changes in estimated glomerular filtration rate over the first year following repeat heart transplant in children and young adults.

BACKGROUND: Renal function is reduced in patients undergoing heart transplant due to hemodynamic compromise, cardiorenal syndrome, and nephrotoxin exposure. No current studies evaluate renal function in retransplants. METHODS: We reviewed all heart transplants at our center from 1995 to 2021 and matched first-time heart transplants with retransplants, based on age at transplant, sex, and race. Estimated glomerular filtration rate (eGFR) was derived from CKiD-U25 calculator using creatinine and measured prior to transplant, 1-week post-transplant, 1-3, 6, and 12 months post-transplant, and recent follow-up. Changes in eGFR were measured within and between patients using a piecewise linear mixed effect model with matching. Exploratory univariate analysis was performed to evaluate pre-transplant risk factors for decreased eGFR. RESULTS: The unmatched cohort included 393 heart transplant recipients, with 47 being retransplants. Thirty-eight patients in both groups with at least 1 year of follow-up underwent matching. Both retransplants and first-time transplants had an initial decline in eGFR. eGFR rebounded to baseline or above baseline at 1-3 months post-transplant, but eGFR in retransplants remained significantly lower. At 1-year post-transplant, the average eGFR was 67.8 ± 4.3 mL/min/1.73 m2 versus 104.7 ± 4.3 mL/min/1.73 m2 (p < .001) in the retransplants and first-time transplants group, respectively. CONCLUSION: This study provides data on anticipated renal trajectory following retransplantation.

Risk factors associated with post-transplant superior caval vein stenosis in paediatric heart transplantation.

Superior caval vein stenosis is a known complication following paediatric heart transplantation. Herein, we sought to assess the incidence of superior caval vein stenosis and need for intervention in a single centre paediatric heart transplantation programme. A retrospective review was performed to identify variables associated with superior caval vein stenosis and need for intervention. Patients were identified based on angiographic and echocardiographic signs of superior caval vein stenosis. Of 204 paediatric heart transplantation recipients, 49 (24.0%) had evidence of superior caval vein stenosis with no need for catheter intervention and 12 (5.9%) had superior caval vein stenosis requiring catheter intervention. Overall, patients with superior caval vein stenosis with and without intervention had more cavopulmonary anastomosis (41.7%; 20.4%), pre-transplant superior caval vein procedures (41.7%; 28.6%), and bicaval approach (100.0%; 98.0%), compared to the group with no stenosis (11.9% and p = 0.015, 12.6% and p = 0.004, 73.4% and p < 0.001, respectively). Smaller recipients and donors were more likely to need intervention. Intervention was also seen more frequently in recipients who were younger at diagnosis (4.7 years) compared to non-intervention (13.3 years; p = 0.040). Re-intervention was required in 16.7% patients (n = 2) and was not associated with any complications.

Postoperative vasoactive inotropic score is predictive of outcomes in pediatric heart transplantation.

Vasoactive inotrope score (VIS) is scarcely studied in pediatric orthotopic heart transplantation (pOHT). We conducted a retrospective review of pOHT (<21 years) recipients. Max VIS and mean VIS were calculated at 0-24 and 24-48 hours post-pOHT. Patients were divided into groups based on ISHLT guidelines: high (>10) and low (≤10). In our group (n = 104), patients with high max and mean VIS groups at 0-24 and 24-48 hours had longer bypass times (high: >130 minutes; low: <108 minutes; P < .05) and high max and mean VIS groups at 0-24 hours had longer ischemic times (high: >215 minutes; low: <192 minutes; P < .05). Patients with high max and mean VIS at 0-24 and 24-48 hours had longer hospital stay, ventilation, inotrope duration, more cardiac events, and acute kidney injury postoperatively (P < .05). High max VIS at 24-48 hours and high mean VIS at 24-48 hours had higher 3-year mortality (P = .04; P = .02). Multivariate analysis confirmed the association of VIS with short-term outcomes. However, VIS was not identified as an independent predictor of mortality. The ROC curve exhibits 10 as the ideal cutoff with area under the curve >0.8 for primary graft dysfunction (PGD).

Family functioning in pediatric heart transplantation: Variables associated with poor outcomes.

Family functioning is integral in a child's life and is linked to quality of life in health as well as disease. This has been scarcely studied in pediatric orthotopic heart transplantation (pOHT). In this study, we evaluate demographic and clinical factors associated with family functioning in this patient population. Pediatric post-transplant families were recruited in an outpatient setting (n = 71). The PedsQL Family Impact Module was administered, along with the Parent and Adolescent Medication Barriers Scales (PMBS; AMBS) and the McArthur socioeconomic scale. Associations between clinical and demographic variables and scaled scores were evaluated. In our sample, patients with congenital heart disease, developmental delay, and enteral feeding had lower total impact (P = .026; P = .011; P = .008) and parent self-reported HRQL scores (P = .018; P = .012; P = .005). Patients with developmental delay and enteral feeding also had lower family functioning summary scores (P = .025; P = .031). Higher parent educational status was associated with lower total impact scores (P = .043). Higher PMBS scores demonstrated negative correlation with total impact (P < .001), parent self-reported HRQL (P < .001), and family functioning summary scores (P = .003). Multiple linear regression analysis identified developmental delay, parental education, and PMBS as independent variables associated with family functioning. Our study highlights important factors impacting family functioning in pOHT. Developmental delay, higher parental education, and PMBS were associated with poorer family functioning. Our findings emphasize the need for a multi-disciplinary approach including serial psychological assessment and interventions in the management of pOHT patients in order to optimize family functioning.

Thenar Muscle Oxygen Saturation Using Vascular Occlusion Test: A Novel Technique to Study Microcirculatory Abnormalities in Pediatric Heart Failure Patients.

Heart failure (HF) is associated with microcirculatory changes secondary to neuro-humoral imbalance, vascular stiffness and increased sympathetic tone. Near Infra-Red Spectroscopy (NIRS) derived Thenar muscle tissue oxygenation levels (StO2) can provide an estimate of the functional status of microcirculation. There is a paucity of literature regarding evaluation of microcirculation in pediatric subjects with HF. We hypothesized that microcirculation and oxygen saturation dynamics as assessed by Thenar StO2 levels using vascular occlusion test (VOT) would be altered in HF subjects and that these changes may correlate with the severity of heart failure. We prospectively enrolled 60 pediatric subjects (29 healthy control, 31 HF). Baseline StO2 levels were measured using InSpectra™ StO2 probe placed over the Thenar eminence of right hand, followed by a VOT for 3 min, during which the changes in StO2 levels during the occlusion phase and post occlusion phase were recorded. Baseline Thenar StO2 levels (72 ± 8 vs 76 ± 5, p = 0.02) and time to baseline StO2 in seconds (150 ± 70 vs 200 ± 70, p = 0.007) were significantly lower in HF group compared to healthy control (HC). In addition, HF patients had a significantly lower trough StO2 (37 ± 9 vs 42 ± 11%, p = 0.04) and peak StO2 compared to HC (87 ± 8 vs 91 ± 5%, p = 0.01). However, there was no difference in the rate of desaturation, rate of resaturation or time to peak StO2 levels in between the 2 groups. Significant correlation was present between baseline Thenar StO2 levels and NYU Pediatric Heart Failure Index Score (NYU-PHFI) (p = 0.003). This study is the first to report an objective assessment of microcirculation and Thenar tissue oxygen dynamics in pediatric subjects with HF in comparison with HC. Our study suggests altered microcirculation and oxygenation patterns in these subjects as well as correlation with a validated pediatric heart failure clinical score. Large-scale prospective studies are needed to further study the utility of this novel technology in HF subjects.

Anti-LFA-1 induces CD8 T-cell dependent allograft tolerance and augments suppressor phenotype CD8 cells.

The induction of tolerance to transplanted organs is a major objective in transplantation immunology research. Lymphocyte function-associated antigen-1 (LFA-1) interactions have been identified as a key component of the T-cell activation process that may be interrupted to lead to allograft tolerance. In mice, αLFA-1 mAb is a potent monotherapy that leads to the induction of donor-specific transferable tolerance. By interrogating important adaptive and innate immunity pathways, we demonstrate that the induction of tolerance relies on CD8+T-cells. We further demonstrate that αLFA-1 induced tolerance is associated with CD8+CD28-T-cells with a suppressor phenotype, and that while CD8 cells are present, the effector T-cell response is abrogated. A recent publication has shown that CD8+CD28- cells are not diminished by cyclosporine or rapamycin, therefore CD8+CD28- cells represent a clinically relevant population. To our knowledge, this is the first time that a mechanism for αLFA-1 induced tolerance has been described.

Hypoplastic left heart in Turner's syndrome: a primary indication for transplant?

Survival for hypoplastic left heart syndrome patients following the Norwood procedure is 71-90%. Mortality in patients with Turner's syndrome and hypoplastic left heart syndrome after conventional palliation (Norwood operation) has been reported as high as 80%. This questions the approach of traditional staged palliation. Here, we report a patient with hypoplastic left heart syndrome and Turner's syndrome bridged to orthotopic heart transplantation following a hybrid procedure.

Ectopic expression of Fas Ligand on cardiomyocytes renders cardiac allografts resistant to CD4(+) T-cell mediated rejection.

Fas Ligand limits inflammatory injury and permits allograft survival by inducing apoptosis of Fas-bearing lymphocytes. Previous studies have shown that the CD4(+) T-cell is both sufficient and required for murine cardiac allograft rejection. Here, utilizing a transgenic mouse that over-expresses Fas Ligand specifically on cardiomyocytes as heart donors, we sought to determine if Fas Ligand on graft parenchymal cells could resist CD4(+) T-cell mediated rejection. When transplanted into fully immunocompetent BALB/c recipients Fas Ligand transgenic hearts were acutely rejected. However, when transplanted into CD4(+) T-cell reconstituted BALB/c-rag(-/-) recipients, Fas Ligand hearts demonstrated long-term survival. These results indicate that Fas Ligand over-expression on cardiomyocytes can indeed resist CD4(+) T-cell mediated cardiac rejection and suggests contact dependence between Fas Ligand expressing graft parenchymal cells and the effector CD4(+) T-cells.

Comprehensive Approach to the Management of Patients with HLHS: Analysis of 100 Consecutive Neonates.

BACKGROUND: We report our comprehensive approach to patients with hypoplastic left heart syndrome (HLHS) and describe our outcomes in 100 consecutive neonates. METHODS: One-hundred consecutive neonates (2015-2023) were stratified into 3 pathways: Pathway(1): 77/100=77% were standard-risk and underwent initial Norwood (Stage 1). Pathway(2): 10/100=10% were high-risk with noncardiac risk factors and underwent initial Hybrid Stage 1. Pathway(3): 13/100=13% were high-risk with cardiac risk factors: 10 underwent initial Hybrid Stage 1 + ventricular assist device insertion (HYBRID+VAD), while 3 underwent primary transplantation. RESULTS: One-year mortality=9/100=9%. Pathway(1): Operative Mortality for initial Norwood (Stage 1)=2/77=2.6%. Of 75 survivors of Norwood (Stage 1): 72 underwent successful Glenn, 2 underwent successful biventricular repair, and 1 underwent successful cardiac transplantation. Pathway(2): Operative Mortality for initial Hybrid Stage 1 without VAD=1/10=10%. Of 9 survivors of Hybrid (Stage 1): 4 underwent successful cardiac transplantation, 2 died while awaiting cardiac transplantation, 3 underwent Comprehensive Stage 2 (with 1 death), and 1 underwent successful biventricular repair. Pathway(3): Of 10 HYBRID+VAD: 7/10=70% underwent successful cardiac transplantation and are alive today and 3/10=30% died on VAD while awaiting transplantation. Median VAD support time=134 days (range=56-226). (Two of three patients who were bridged-to-transplant with prostaglandin underwent successful transplantation and one died while awaiting transplantation.) CONCLUSIONS: A comprehensive approach to the management of patients with HLHS is associated with Operative Mortality after Norwood of 2/77=2.6% and an overall one-year mortality of 9/100=9%. 10/100 patients=10% were stabilized with HYBRID+VAD while awaiting transplantation. VAD facilitates survival on the waiting list during prolonged wait times.

Early predictors of survival to and after heart transplantation in children with dilated cardiomyopathy.

BACKGROUND: The importance of clinical presentation and pretransplantation course on outcome in children with dilated cardiomyopathy listed for heart transplantation is not well defined. METHODS AND RESULTS: The impact of age, duration of illness, sex, race, ventricular geometry, and diagnosis of myocarditis on outcome in 261 children with dilated cardiomyopathy enrolled in the Pediatric Cardiomyopathy Registry and Pediatric Heart Transplant Study was studied. End points included listing as United Network for Organ Sharing status 1, death while waiting, and death after transplantation. The median age at the time of diagnosis was 3.4 years, and the mean time from diagnosis to listing was 0.62±1.3 years. Risk factors associated with death while waiting were ventilator use and older age at listing in patients not mechanically ventilated (P=0.0006 and P=0.03, respectively). Shorter duration of illness (P=0.04) was associated with listing as United Network for Organ Sharing status 1. Death after transplantation was associated with myocarditis at presentation (P=0.009), nonwhite race (P<0.0001), and a lower left ventricular end-diastolic dimension z score at presentation (P=0.04). In the myocarditis group, 17% (4 of 23) died of acute rejection after transplantation. CONCLUSIONS: Mechanical ventilator use and older age at listing predicted death while waiting, whereas nonwhite race, smaller left ventricular dimension, and myocarditis were associated with death after transplantation. Although 97% of children with clinically or biopsy-diagnosed myocarditis at presentation survived to transplantation, they had significantly higher posttransplantation mortality compared with children without myocarditis, raising the possibility that preexisting viral infection or inflammation adversely affects graft survival.

The hemodynamic response to dexmedetomidine loading dose in children with and without pulmonary hypertension.

BACKGROUND: Dexmedetomidine, an α-2 receptor agonist, is widely used in children with cardiac disease. Significant hemodynamic responses, including systemic and pulmonary vasoconstriction, have been reported after dexmedetomidine administration. Our primary goal of this prospective, observational study was to quantify the effects of dexmedetomidine initial loading doses on mean pulmonary artery pressure (PAP) in children with and without pulmonary hypertension. METHODS: Subjects were children undergoing cardiac catheterization for either routine surveillance after cardiac transplantation (n = 21) or pulmonary hypertension studies (n = 21). After anesthetic induction with sevoflurane and tracheal intubation, sevoflurane was discontinued and anesthesia was maintained with midazolam 0.1 mg/kg i.v. (or 0.5 mg/kg orally preoperatively) and remifentanil i.v. infusion 0.5 to 0.8 µg/kg/min. Ventilation was mechanically controlled to maintain PCO2 35 to 40 mm Hg. When end-tidal sevoflurane was 0% and fraction of inspired oxygen (FIO2) was 0.21, baseline heart rate, mean arterial blood pressure, PAP, right atrial pressure, pulmonary artery occlusion pressure, right ventricular end-diastolic pressure, cardiac output, and arterial blood gases were measured, and indexed systemic vascular resistance, indexed pulmonary vascular resistance, and cardiac index were calculated. Each subject then received a 10-minute infusion of dexmedetomidine of 1 µg/kg, 0.75 µg/kg, or 0.5 µg/kg. Measurements and calculations were repeated at the conclusion of the infusion. RESULTS: Most hemodynamic responses were similar in children with and without pulmonary hypertension. Heart rate decreased significantly, and mean arterial blood pressure and indexed systemic vascular resistance increased significantly. Cardiac index did not change. A small, statistically significant increase in PAP was observed in transplant patients but not in subjects with pulmonary hypertension. Changes in indexed pulmonary vascular resistance were not significant. CONCLUSION: Dexmedetomidine initial loading doses were associated with significant systemic vasoconstriction and hypertension, but a similar response was not observed in the pulmonary vasculature, even in children with pulmonary hypertension. Dexmedetomidine does not appear to be contraindicated in children with pulmonary hypertension.

Assessment of parental decision making in congenital heart disease, cardiomyopathy and heart transplantation: an observational study analysing decisional characteristics and preferences.

OBJECTIVE: We explore shared decision making (DM) in guardians of children with heart disease by assessing the desired weight of influence on DM and factors that may alter the relative weight of parent or medical team influence. METHODS: Guardians of patients <21 years and admitted >1 week in the paediatric cardiac intensive care unit (PCICU) were recruited. Twelve vignettes were designed including technical (antibiotic selection, intubation, peripherally inserted central catheter placement, ventricular assist device placement, heart transplant, organ rejection, heart rhythm abnormalities and resuscitation effort) and non-technical vignettes (cessation of life-sustaining therapies, depression treatment, obesity and palliative care referral). Participants responded to questions on DM characteristics and one question querying preference for relative weight of parent or medical team influence on DM. RESULTS: Of 209 participants approached, 183 were included. Most responded with equal desire of medical team and parental influence on DM in all vignettes (range 41.0%-66.7%). Technical scenarios formed one cluster based on DM characteristics, compared with non-technical scenarios. Factors that increase the relative weight of parental influence on DM include desired input and involvement in big-picture goals (OR 0.274, CI [0.217 to 0.346]; OR 0.794, CI [0.640 to 0.986]). Factors that increase the relative weight of medical team influence on DM include perception of medical expertise needed (OR 1.949 [1.630 to 2.330]), urgency (OR 1.373 [1.138 to 1.658]), benefit (OR 1.415 [1.172 to 1.710]), number of PCICU admissions (OR 1.134 [1.024 to 1.256]) and private insurance (OR 1.921 [1.144 to 3.226]). CONCLUSION: Although factors may alter the weight of influence on DM, most parents desire equal parental and medical team influence on DM.

An Analysis of 186 Transplants for Pediatric or Congenital Heart Disease: Impact of Pretransplant VAD.

BACKGROUND: We reviewed our management strategy and outcome data for all 181 patients with pediatric or congenital heart disease who received 186 heart transplants from January 1, 2011, to March 1, 2022, and evaluated the impact of pretransplant ventricular assist device (VAD). METHODS: Continuous variables are presented as mean (SD); median [interquartile range] (range). Categorical variables are presented as number (percentage). Univariable associations with long-term mortality were assessed with Cox proportional hazards models. Impact of pretransplant VAD on survival was estimated with multivariable models. RESULTS: Pretransplant VAD was present in 53 of 186 transplants (28.5%). Patients with VAD were younger (years): 4.8 (5.6); 1 [0.5-8] (0.1-18) vs 12.1 (12.7); 10 [0.7-17] (0.1-58); P = .0001. Patients with VAD had a higher number of prior cardiac operations: 3.0 (2.3); 2 [1-4] (1-12) vs 1.8 (1.9); 2 [0-3] (0-8); P = .0003. Patients with VAD were also more likely to receive an ABO-incompatible transplant: 10 of 53 (18.9%) vs 9 of 133 (6.8%); P = .028. Univariable associations with long-term mortality included: In multivariable analysis, pretransplant VAD did not impact survival while controlling for each one of the factors shown in univariable analysis to be associated with long-term mortality. Kaplan-Meier 5-year survival (95% CI) was 85.8% (80.0%-92.1%) for all patients, 84.3% (77.2%-92.0%) without pretransplant VAD, and 91.1% (83.1%-99.9%) with pretransplant VAD. CONCLUSIONS: Our single-institution analysis of 181 patients receiving 186 heart transplants for pediatric or congenital heart disease over 11.25 years reveals similar survival in patients with (n = 51) and without (n = 130) pretransplant VAD. The presence of a pretransplant VAD is not a risk factor for mortality after transplantation for pediatric or congenital heart disease.

Heart Transplantation in Patients Less Than 18 Years of Age: Comparison of 2 Eras Over 36 Years and 323 Transplants at a Single Institution.

BACKGROUND: We reviewed our management strategy and outcome data for all 311 patients less than 18 years of age who underwent 323 heart transplants at our institution (1986 to 2022) in order to assess changes in patterns of practice and outcomes over time and to compare two consecutive eras: era 1 (154 heart transplants [1986 to 2010]) and era 2 (169 heart transplants [2011 to 2022]). STUDY DESIGN: Descriptive comparisons between the two eras were performed at the level of the heart transplant for all 323 transplants. Kaplan-Meier survival analyses were performed at the level of the patient for all 311 patients, and log-rank tests were used to compare groups. RESULTS: Transplants in era 2 were younger (6.6 ± 6.5 years vs 8.7 ± 6.1 years, p = 0.003). More transplants in era 2 were in infants (37.9% vs 17.5%, p < 0.0001), had congenital heart disease (53.8% vs 39.0%, p < 0.010), had high panel reactive antibody (32.1% vs 11.9%, p < 0.0001), were ABO-incompatible (11.2% vs 0.6%, p < 0.0001), had prior sternotomy (69.2% vs 39.0%, p < 0.0001), had prior Norwood (17.8% vs 0%, p < 0.0001), had prior Fontan (13.6% vs 0%, p < 0.0001), and were in patients supported with a ventricular assist device at the time of heart transplant (33.7% vs 9.1%, p < 0.0001). Survival at 1, 3, 5, and 10 years after transplant was as follows: era 1 = 82.4% (76.5 to 88.8), 76.9% (70.4 to 84.0), 70.7% (63.7 to 78.5), and 58.8% (51.3 to 67.4), respectively; era 2 = 90.3% (85.7 to 95.1), 85.4% (79.7 to 91.5), 83.0% (76.7 to 89.8), and 66.0% (49.0 to 88.8), respectively. Overall Kaplan-Meier survival in era 2 was better (log-rank p = 0.03). CONCLUSIONS: Patients undergoing cardiac transplantation in the most recent era are higher risk but have better survival.

An Analysis of 183 Heart Transplants for Pediatric or Congenital Heart Disease-Impact of High Panel Reactive Antibody.

BACKGROUND: We reviewed our management strategy and outcome data for all 179 patients with pediatric and/or congenital heart disease who underwent 183 heart transplants from January 1, 2011, to December 31, 2021, and evaluated the impact of elevated panel reactive antibody (PRA). METHODS: High PRA was defined as PRA >10%. Univariate associations with long-term survival were assessed with Cox proportional hazards models. Impact of high PRA on survival was estimated with multivariable models. RESULTS: PRA >10% was present in 60 of 183 transplants (32.8%), who were more likely to have prior cardiac surgery, higher number of prior cardiac operations, prior sternotomy, prior heart transplant, and positive crossmatch (24 of 60 [40.0%] vs 11 of 123 [8.9%], P < .0001). Univariate associations with long-term survival include acquired heart disease vs congenital or retransplant (hazard ratio [HR], 0.18; 95% CI, 0.053-0.593; P = .005), prior cardiac surgery (HR, 5.6; 95% CI, 1.32-23.75; P = .020), number of prior cardiac operations (HR, 1.3 for each additional surgery; 95% CI, 1.12-1.50; P = .0004), single ventricle (HR, 2.4; 95% CI, 1.05-5.48; P = .038), and preoperative renal dysfunction (HR, 3.4; 95% CI, 1.43-7.49; P = .002). In multivariate analysis, high PRA does not impact survival when controlling for each of the factors shown in univariable analysis to be associated with long-term survival. The Kaplan-Meier method provided the following survival estimates at 1 year (95% CI) and 5 years (95% CI) after cardiac transplantation: All patients, 93.6% (89.9%-97.3%) and 85.8% (80.0%-92.1%); PRA <10%, 96.6% (93.4%-99.9%) and 86.7% (79.6%-94.3%); and PRA >10%, 86.7% (78.0%-96.4%) and 83.8% (74.0%-95.0%). Despite high PRA being associated with higher mortality at 1 year (14.9% vs 3.8%, P = .035), no significant difference exists in Kaplan-Meier overall survival at 5 years posttransplant in patients with and without high PRA (log-rank P = .4). CONCLUSIONS: In our cohort, 5-year survival in patients with high PRA (PRA >10%) is similar to that in patients without high PRA (PRA <10%), despite the presence of more risk factors in those with high PRA. Individualized immunomodulatory strategies can potentially mitigate the risk of high PRA.

Palliation Plus Ventricular Assist Device Insertion in 15 Neonates and Infants With Functionally Univentricular Circulation.

BACKGROUND: We report 15 high-risk neonates and infants with functionally univentricular circulation stabilized with initial surgical palliation plus ventricular assist device (VAD) insertion (PALLIATION+VAD) in preparation for transplantation. METHODS: Fifteen functionally univentricular patients with ductal-dependent systemic circulation (8 hypoplastic left heart syndrome, 1 hypoplastic left heart syndrome-related malformation: 7 neonates, 2 infants) or ductal-dependent pulmonary circulation (6 hypoplastic right heart syndrome: 5 neonates, 1 infant) presented with anatomical and/or physiological features associated with increased risk for conventional univentricular palliation (large coronary sinusoids with ventricular-dependent coronary circulation, severe systemic atrioventricular valvar regurgitation, cardiogenic shock, or restrictive atrial septum). PALLIATION+VAD for patients with ductal-dependent systemic circulation was: VAD insertion plus application of bilateral pulmonary bands, stent placement in the arterial duct, and atrial septectomy, if needed. PALLIATION+VAD for patients with ductal-dependent pulmonary circulation was: VAD insertion plus stent placement in the arterial duct or systemic-to-pulmonary artery shunt with pulmonary arterioplasty, if needed. RESULTS: At PALLIATION+VAD, median age was 20 days (range, 4-143 days) and median weight was 3.47 kg (range, 2.43-4.86 kg). Ten patients (67%) survived and 5 patients (33%) died. All ten survivors are at home doing well after successful transplantation. Only 2 of 10 survivors (20%) required intubation >10 days after PALLIATION+VAD. Median length of VAD support for all 15 patients was 138 days (range, 56-226 days). CONCLUSIONS: High-risk neonates with functionally univentricular hearts who are suboptimal candidates for conventional palliation can be successfully stabilized with pulsatile VAD insertion along with initial palliation while awaiting cardiac transplantation; these patients may be extubated, enterally nourished, and optimized for transplantation while on VAD.

A Comprehensive Approach to the Management of Patients With HLHS and Related Malformations: An Analysis of 83 Patients (2015-2021).

Background: Some patients with hypoplastic left heart syndrome (HLHS) and HLHS-related malformations with ductal-dependent systemic circulation are extremely high-risk for Norwood palliation. We report our comprehensive approach to the management of these patients designed to maximize survival and optimize the utilization of donor hearts. Methods: We reviewed our entire current single center experience with 83 neonates and infants with HLHS and HLHS-related malformations (2015-2021). Standard-risk patients (n = 62) underwent initial Norwood (Stage 1) palliation. High-risk patients with risk factors other than major cardiac risk factors (n = 9) underwent initial Hybrid Stage 1 palliation, consisting of application of bilateral pulmonary bands, stent placement in the patent arterial duct, and atrial septectomy if needed. High-risk patients with major cardiac risk factors (n = 9) were bridged to transplantation with initial combined Hybrid Stage 1 palliation and pulsatile ventricular assist device (VAD) insertion (HYBRID + VAD). Three patients were bridged to transplantation with prostaglandin. Results: Overall survival at 1 year = 90.4% (75/83). Operative Mortality for standard-risk patients undergoing initial Norwood (Stage 1) Operation was 2/62 (3.2%). Of 60 survivors: 57 underwent Glenn, 2 underwent biventricular repair, and 1 underwent cardiac transplantation. Operative Mortality for high-risk patients with risk factors other than major cardiac risk factors undergoing initial Hybrid Stage 1 palliation without VAD was 0/9: 4 underwent transplantation, 1 awaits transplantation, 3 underwent Comprehensive Stage 2 (with 1 death), and 1 underwent biventricular repair. Of 9 HYBRID + VAD patients, 6 (67%) underwent successful cardiac transplantation and are alive today and 3 (33%) died while awaiting transplantation on VAD. Median length of VAD support was 134 days (mean = 134, range = 56-226). Conclusion: A comprehensive approach to the management of patients with HLHS or HLHS-related malformations is associated with Operative Mortality after Norwood of 2/62 = 3.2% and a one-year survival of 75/83 = 90.4%. A subset of 9/83 patients (11%) were stabilized with HYBRID + VAD while awaiting transplantation. VAD facilitates survival on the waiting list during prolonged wait times.

Pediatric heart transplantation after declaration of cardiocirculatory death.

In three infants awaiting orthotopic cardiac transplantation, transplantation was successfully performed with the use of organs from donors who had died from cardiocirculatory causes. The three recipients had blood group O and were in the highest-risk waiting-list category. The mean age of donors was 3.7 days, and the mean time to death after withdrawal from life support was 18.3 minutes. The 6-month survival rate was 100% for the 3 transplant recipients and 84% for 17 control infants who received transplants procured through standard organ donation. The mean number of rejection episodes among the three infants during the first 6 months after surgery was 0.3 per patient, as compared with 0.4 per patient among the controls. Echocardiographic measures of ventricular size and function at 6 months were similar among the three infants and the controls (left ventricular shortening fraction, 43.6% and 44.9%, respectively; P=0.73). No late deaths (within 3.5 years) have occurred in the three infants, and they have had functional and immunologic outcomes similar to those of controls. Mortality while awaiting a transplant is an order of magnitude higher in infants than in adults, and donors who died from cardiocirculatory causes offer an opportunity to decrease this waiting-list mortality.

Outcome of acute graft rejection associated with hemodynamic compromise in pediatric heart transplant recipients.

We sought to analyze the outcome of hemodynamically significant acute graft rejection in pediatric heart transplant recipients from a single-center experience. Acute graft rejection remains a major cause of morbidity and mortality for patients who undergo orthotopic heart transplantation and has been associated with the severity of the rejection episode. A retrospective review of all children experiencing a hemodynamically significant rejection episode after orthotopic heart transplantation was performed. Fifty-three patients with 54 grafts had 70 rejection episodes requiring intravenous inotropic support. Forty-one percent of these patients required high-dose inotropic support, with the remaining 59% of patients requiring less inotropic support. Overall graft survival to hospital discharge was 41% for patients in the high-dose group compared to 94% in the low-dose group. Six-month graft survival in patients who required high-dose inotropes remained at 41% compared to 44% in the low-dose group. Hemodynamically significant acute graft rejection in pediatric heart transplant recipients is a devastating problem with poor short- and long-term outcomes. Survival to hospital discharge is dismal in patients who require high-dose inotropic support. In contrast, survival to discharge is quite good in patients who require only low-dose inotropic support; however, six-month graft survival in this group is low secondary to a high incidence of graft failure related to worsening or aggressive transplant coronary artery disease.

Long-term outcome of palliation with internal pulmonary artery bands after primary heart transplantation for hypoplastic left heart syndrome.

The purpose of this study was to describe the long-term outcome of infants with hypoplastic left heart syndrome (HLHS) who underwent placement of internal pulmonary artery bands as part of a transcatheter palliation procedure followed by primary heart transplantation. Transcatheter palliation included stenting of the ductus arteriosus, decompression of the left atrium by atrial septostomy, and internal pulmonary artery band placement. Cardiac hemodynamics, pulmonary artery architecture, and pulmonary artery growth since transplantation are described. Nine infants with HLHS had internal pulmonary artery bands placed and underwent successful heart transplant. No infant required reconstruction of the pulmonary arteries at the time of transplant. At 1 year after transplant, all of the recipients had normal mean pulmonary artery pressure, pulmonary vascular resistance, and transpulmonary gradient. Pulmonary angiography performed at 1 year after transplant demonstrated no distortion of pulmonary artery anatomy with significant interval growth of the branch pulmonary arteries. There was 100% survival to hospital discharge after transplant in this cohort of infants. Transcatheter placement of internal pulmonary artery bands for HLHS offers protection of the pulmonary vascular bed while preserving pulmonary artery architecture and growth with good long-term outcome.