Review on clinician bias and its impact on racial and socioeconomic disparities in pediatric heart transplantation.

This expert review seeks to highlight implicit bias in health care, transplant medicine, and pediatric heart transplantation to focus attention on the role these biases may play in the racial/ethnic and socioeconomic disparities noted in pediatric heart transplantation. This review breaks down the transplant decision making process to highlight points at which implicit bias may affect outcomes and discuss how the science of human decision making may help understand these complex processes.

Contemporary Provider Management Practices and Attitudes Toward Referral for Advanced Heart Failure Therapies in Fontan Patients Across North America.

BACKGROUND: To date, no reports have described clinicians' management practices for patients with Fontan circulatory failure or their understanding of risk factors for mortality and transplant outcomes in these patients. METHODS AND RESULTS: A cross-sectional survey of caregivers across North America was conducted from February to September 2020. Responses were compared by primary specialty (heart failure/transplant vs non-heart failure/transplant), years of experience (early, mid, and late career), and Fontan center volume (low, medium, and high). Of 400 responses, the majority were from general cardiologists (111, 28%) followed by heart failure/transplant specialists (93, 23%). Although most agreed that patients with Fontan physiology will have signs/symptoms of heart failure (369 [93%]) and eventuate in heart transplant (286 [72%]), many disagreed (180 [45%]) that routine evaluation by a transplant cardiologist is needed without symptoms. Transplant providers were more likely than non-transplant providers to suggest referral for manifestations of Fontan circulatory failure such as protein-losing enteropathy, plastic bronchitis, liver fibrosis/cirrhosis, and worsening valve regurgitation. Non-transplant providers were more likely to suggest that protein-losing enteropathy, plastic bronchitis, and Fontan-associated liver disease lead to inferior outcomes after transplantation. Early career and transplant providers more favorably viewed ventricular assist device use for Fontan patients failing traditional heart failure therapy (P < .05 for all). CONCLUSIONS: There is significant variation in the management of Fontan patients, including heterogeneous timing of referral of such patients to the heart failure/transplant team, which may have implications for future outcomes.

Fontan-associated plastic bronchitis waitlist and heart transplant outcomes: A PHTS analysis.

Plastic bronchitis is a rare post-Fontan complication with limited treatment options. Heart transplantation has evolved as a potential curative option, but outcomes have not been well-defined. This study aims to assess contemporary waitlist and post-transplant outcomes in patients with plastic bronchitis. All Fontan patients were identified in the PHTS database (2010 - 2018). Waitlist and post-transplant outcomes were compared between Fontan patients with and without plastic bronchitis. Competing outcomes and Kaplan-Meier analyses were used to assess the impact of plastic bronchitis on waitlist and post-transplant survival. A secondary analysis excluded those with PLE from the comparison cohort. Of 645 Fontan patients listed for heart transplant, 69 (11%) had plastic bronchitis. At listing, patients with plastic bronchitis were younger (8.9 vs 11.1 years, P = .02), but had few other differences in baseline characteristics. A fewer Fontan patients with plastic bronchitis were listed in the more recent era (46 [15.4%] in 2010-2014 vs 23 [6.6%] in 2015-2018, P < .01). Overall, there was no difference in waitlist (P = .30) or post-transplant (P = .66) survival for Fontan patients with and without plastic bronchitis. The results were similar after excluding patients with PLE. Contrary to prior reports, this relatively large series showed that plastic bronchitis did not have a negative impact on survival to or after heart transplantation in Fontan patients. Our study also found a 50% reduction in listing in the current era, which may indicate evolution in management of Fontan patients.

Variability in clinical decision-making for ventricular assist device implantation in pediatrics.

BACKGROUND: Minimal data exist on clinical decision-making in VAD implantation in pediatrics. This study aims to identify areas of consensus/variability among pediatric VAD physicians in determining eligibility and factors that guide decision-making. METHODS: An 88-item survey with clinical vignettes was sent to 132 pediatric HT cardiologists and surgeons at 37 centers. Summary statistics are presented for the variables assessed. RESULTS: Total respondents were 65 (72% cardiologists, 28% surgeons) whose centers implanted 1-5 (34%), 6-10 (40%), or >10 (26%) VADs in the past year. Consensus varied by patients' age, diagnosis, and Pedimacs profile. Highest agreement to offer VAD (97%) was a mechanically ventilated teenager with dilated cardiomyopathy. Patients stable on inotropes were less likely offered VAD (11%-25%). SV infant with Pedimacs profile 2 had the most varied responses: 37% offered VAD; estimated survival ranged from 15% to 90%. Variables considered for VAD eligibility included mild developmental delays (100% offered VAD), moderate-severe behavioral concerns (46%), cancer in remission >2 years (100%), active malignancy with good prognosis (68%) or uncertain prognosis (36%), and BMI >35 (74%) or <15 (69%). Most respondents (91%) would consider destination therapy VADs in pediatrics, though not currently feasible at 1/3 of centers. Factors with greatest influence on decision-making included HT candidacy, families' goals of care, and risks of complications. CONCLUSIONS: Significant variation exists among pediatric VAD physicians when determining VAD eligibility and estimating survival, which can lead to differences in access to emerging technologies across institutions. Further work is needed to understand and mitigate these differences.

Review of interactions between high-risk pediatric heart transplant recipients and marginal donors including utilization of risk score models.

BACKGROUND: Donor organ acceptance practices vary among pediatric heart transplant professionals. We sought to understand what is known about the interactions between the "high-risk" recipient and the "marginal donor," and how donor risk scores can impact this discussion. METHODS: A systematic review of published literature on pediatric HTx was undertaken with the assistance of a medical librarian. Two authors independently assessed search results, and papers were reviewed for inclusion. RESULTS: We found that there are a large number of individual factors, and clusters of factors, that have been used to label individual recipients "high-risk" and individual donors "marginal." The terms "high-risk recipient" and "marginal donor" have been used broadly in the literature making it virtually impossible to make comparisons between publications. In general, the data support that patients who could be easily agreed to be "sicker recipients" are at more risk compared to those who are clearly "healthier," albeit still "sick enough" to need transplantation. Given this variability in the literature, we were unable to define how being a "high-risk" recipient interplays with accepting a "marginal donor." Existing risk scores are described, but none were felt to adequately predict outcomes from factors available at the time of offer acceptance. CONCLUSIONS: We could not determine what makes a donor "marginal," a recipient "high-risk," or how these factors interplay within the specific recipient-donor pair to determine outcomes. Until there are better risk scores predicting outcomes at the time of organ acceptance, programs should continue to evaluate each organ and recipient individually.

Variability in donor selection among pediatric heart transplant providers: Results from an international survey.

There is considerable variability in donor acceptance practices among adult heart transplant providers; however, pediatric data are lacking. The aim of this study was to assess donor acceptance practices among pediatric heart transplant professionals. The authors generated a survey to investigate clinicians' donor acceptance practices. This survey was distributed to all members of the ISHLT Pediatric Council in April 2018. A total of 130 providers responded from 17 different countries. There was a wide range of acceptable criteria for potential donors. These included optimal donor-to-recipient weight ratio (lower limit: 50%-150%, upper limit: 120%-350%), maximum donor age (25-75 years), and minimum acceptable left ventricular EF (30%-60%). Non-US centers demonstrated less restrictive donor selection criteria and were willing to accept older donors (50 vs 35 years, P < 0.001), greater size discrepancy (upper limit weight ratio 250% vs 200%, P = 0.009), and donors with a lower EF (45% vs 50%, P < 0.001). Recipient factors were most influential in the decision to accept marginal donors including recipients requiring ECMO support, ventilator support, and highly sensitized patients with a negative XM. However, programmatic factors impacted the decision to decline marginal donors including recent programmatic mortalities and concerns for programmatic restrictions from regulatory bodies. There is significant variation in donor acceptance practices among pediatric heart transplant professionals. Standardization of donor acceptance practices through the development of a consensus statement may help to improve donor utilization and reduce waitlist mortality.

Variations in Criteria and Practices for Heart Transplantation Listing Among Pediatric Transplant Cardiologists.

Ethical issues in pediatric heart transplantation (Htx) include resource allocation, benefit, and burden assessment in high-risk recipients, and informed consent. Practice patterns and decision-making was investigated using an internet survey with 47-multiple choice items and vignette-based questions. Of 43 pediatric Htx cardiologists contacted, 28 (65%) responded. Respondents reported that an overall median 1-month survival of 73% (range 50-100%), 1-year survival of 70% (range 50-85%), 5-year survival of 50% (range 40-85%), and 10-year survival of 50% (range 25-85%) was adequate to offer Htx. Based on vignettes presented, 100% of those surveyed would offer Htx to a straightforward 12-year old with end-stage dilated cardiomyopathy and a 7-year old with hypoplastic left heart syndrome with protein losing enteropathy. Thirty percent of physicians would offer Htx to a patient status post a Fontan procedure with mutliple co-morbidities. Seventy-five percent of physicians would offer Htx despite proven non-adherence. Considerable variability exists in the practice patterns of pediatric heart transplant cardiologists with regards to decision-making while evaluating patients for listing. Disagreements among pediatric Htx cardiologists exist when there are concerns for non-adherence and associated multiple co-morbidities. Further work is needed to understand these variations and develop consensus for pediatric Htx organ allocation.

Successful Bridge-to-Transplant of Functionally Univentricular Patients With a Modified Continuous-Flow Ventricular Assist Device.

A continuous flow extracorporeal ventricular assist device (VAD) was modified to support functionally univentricular infants and children awaiting heart transplantation. A centrifugal VAD, designed to flow from 1.5 to 8 L/min, was used as a bridge-to-transplant in four patients with functionally univentricular circulation. A variable restrictive recirculation shunt permitted lower flow ranges in small patients. In hypoxic patients, an oxygenator was incorporated into the circuit. From 2012 to 2015, the modified VAD was placed in four patients with Glenn physiology. Age ranged from 0.97 to 6.98 years (median = 2.2 yrs). Body surface area ranged from 0.41 to 0.84 m2 (median = 0.54 m2 ). One patient was on extracorporeal membrane oxygenation prior to VAD. A recirculation shunt was used in three patients. Three patients required temporary use of an oxygenator for 4, 10, and 27 days. Median time on the VAD was 32.3 days (range = 23-43 days). A decrease in the cavopulmonary pressure was noted in all patients, as was a fall in the B-type natriuretic peptide. Three patients survived transplant and were discharged at 28-82 days post-transplantation. One patient died after 35 days of support. Two patients experienced major bleeding events. Two patients experienced cerebrovascular accidents, one major and one minor. The centrifugal VAD successfully supported palliated functionally univentricular patients awaiting heart transplantation. The modified recirculation shunt facilitated the successful support of patients in whom optimal flows were substantially lower than that recommended by the manufacturer. The continuous-flow VAD effectively decompressed the cavopulmonary system. The design allowed placement of an in-line oxygenator in hypoxic patients. Further investigation is required to decrease the thromboembolic events, and associated morbidity, in patients supported with this device.

Reducing Fluoroscopic Radiation Exposure During Endomyocardial Biopsy in Pediatric Transplant Recipients.

Endomyocardial biopsy (EMB) with fluoroscopy is used for rejection surveillance in pediatric heart transplantation. Lowering frame rate may reduce radiation, but decreases temporal resolution and image quality. We undertook a quality initiative reducing frame rate from 10 frames per second (FPS) to 5 FPS. To assess whether lowering frame rate can reduce radiation exposure without compromising safety, data on EMBs from 9/2009 to 4/2013 without angiography or intervention were reviewed. Effective dose was calculated from dose area product (DAP) and fluoroscopy time. Complications were reviewed. Independent t test compared pre- and post-data and a general linear model were used to control for confounders. Paired t test of most proximate data was used for pts with EMB before and after our change. Eighty-six patients had 543 EMB. After adjusting for weight, attending, and presence of a fellow, the lower FPS group had a 60.3% reduction in DAP (p < 0.0001) and 53.8% drop in effective dose (p < 0.0001). Fluoroscopy time did not differ. Twenty-eight pts had EMBs both before and after the FPS change. Pair-wise analysis of this group demonstrated a 33% reduction in DAP (p < 0.05) and 37% drop in effective dose (p < 0.01), without difference in fluoroscopy time. No patient had an increase in TR > 1 grade by ECHO. There were no deaths or perforations. Lowering the frame rate reduces radiation exposure by >50% without compromising safety. Efforts to further minimize radiation exposure of this vulnerable population should be considered.

Strategies to Prevent Cast Formation in Patients with Plastic Bronchitis Undergoing Heart Transplantation.

Plastic bronchitis, a rare complication after Fontan palliation, carries a high morbidity and mortality risk. Heart transplantation is an effective treatment option, but casts may occur in the early post-operative period. We present a case series detailing peri-operative management strategies to minimize morbidity and mortality related to plastic bronchitis in patients undergoing heart transplantation. Patient 1 received no treatment pre-, intra-, or post-transplant for prevention of bronchial casts and developed severe respiratory acidosis 18 h following transplant. Emergent bronchoscopy was performed and a large obstructive cast was removed. The patient recovered and received inhaled tissue plasminogen activator (tPA) for 5 days. Patient 2 received inhaled tPA before, during, and for 5 days after transplantation and no bronchial casts developed. Patient 3 underwent intraoperative bronchoscopy just prior to implantation revealing no casts. The patient underwent non-urgent, preemptive bronchoscopy on post-transplant days 1, 3, and 4, removing several partially obstructive bronchial blood clots/casts, with no casts thereafter. Heart transplantation results in eventual resolution of plastic bronchitis. Residual bronchial casts can still be problematic in the peri-operative period. Airway clearance with inhaled tPA or bronchoscopy may prevent the need for prolonged mechanical ventilation and reduce post-operative morbidity in this unique population.

Extracardiac Fontan fenestration using the SafeSept transseptal guidewire and snare-controlled diabolo-shaped covered-stent placement.

Transcatheter Fontan fenestration is a valuable option in situations of prolonged pleural drainage or low cardiac output in patients with failing Fontan circulation. This procedure relies on controlled baffle perforation without separation of the Fontan circuit from the pulmonary venous atrium, and placement of an accurately sized covered stent. We report a novel technique for transcatheter extracardiac Fontan fenestration using the SafeSept transseptal guidewire® and snare-controlled diabolo-shaped covered stent placement.

New-onset diabetes mellitus after heart transplantation in children - Incidence and risk factors.

Diabetes mellitus is a recognized complication of SOT in adults and is associated with decreased graft and patient survival. Little is known about NOD in pediatric HT recipients. We aimed to characterize the incidence and describe risk factors for development of NOD after HT in children. Children who developed diabetes after HT were identified from the OPTN database. Demographic and clinical data before and after transplant were compared between patients with and without NOD. A total of 2056 children were included, 56% were male, 54% were Caucasian, and 62% had cardiomyopathy prior to HT. NOD developed in 219 children (11%) after HT. The incidence of NOD was 2.4, 9.0, and 10.4% at one, five, and 10 yr after HT, respectively. Obesity (HR: 4.32), dialysis prior to transplant (HR: 2.38), African American race (HR: 1.86), transplant before year 2000 (HR: 1.82), female gender (HR: 1.68), and older age at transplant (HR: 1.28) were independent predictors of NOD. The major modifiable risk factor for NOD is obesity, imparting the maximum hazard. Improved surveillance for diabetes in high-risk patients and specific prevention and intervention strategies are imperative in this population.

Diagnosis and Diagnostic Modalities in Pediatric Patients with Elevated Troponin.

Care of adults with coronary artery disease focuses on troponins to rapidly move patients to catheterization. Troponins are increasingly drawn in children, but emergent catheterization may not be indicted. We sought to establish etiologies of troponin elevation and ascertain the yield of diagnostic tests, in this population. Retrospective review of patients from January 1, 2002, to December 31, 2011, who had any elevated troponin during the study period. Patients were excluded for recent cardiac surgery, "significant" congenital heart disease, if they were neonates in the NICU or were on ECMO. Twenty-four patients made up our study group: 17/24 (71 %) had myocarditis or cardiomyopathy. Three had coronary-related diagnoses: 1 ALCAPA and 2 Kawasaki syndrome. The most useful testing for making or confirming the diagnoses included ECG, CXR and ECHO. Fourteen had right heart catheterization which was useful in 10/14. Nine had MRI which was useful in 7/9 (all five cases of suspected myocarditis). Left heart catheterization was completed in 10/24 cases, but in no case made or changed the diagnosis. This study confirms that children with elevated troponins differ from adults. The most common cause is myocarditis or cardiomyopathy, whereas coronary-related ischemia is rare. Diagnosis with ECG, CXR and ECHO is typically adequate. Focused use of right heart catheterization and MRI may be useful. In pediatric patients with elevated troponins, left heart catheterization and coronary angiography should be reserved for a highly selective group, and adult "door-to-balloon time" protocols should not be applied routinely.

Growth of the atrial septum after Amplatzer device closure of atrial septal defects in young children.

BACKGROUND: Trans-catheter closure of atrial septal defects (ASD) with the Amplatzer Septal Occluder (ASO) device is safe and effective, but concern over erosions has increased. Devices are placed in growing children but septal growth after ASOs is ill-defined. Understanding the device relationship to cardiac structures as a child grows may help us understand erosions. OBJECTIVE: To define (1) how preprocedural septal measurements change after ASO and (2) the effect of somatic growth on these dimensions. METHODS: Data were collected retrospectively. Echocardiograms were reviewed and rims measured prior to ASO, immediately after ASO, and at follow-up. Demographic, procedural and device data were collected. RESULTS: Thirty-three patients were enrolled; mean age 5.2 ± 3.2 years with 4.0 ± 2.2 years follow-up. All septal measurements decreased after ASO. Thirty-one of 33 devices (94%) contacted the aortic root after ASO; all remained in contact at follow-up with only the IVC rim growing significantly over time. Change in BSA predicted an asymmetric septal growth with increases in superior (P = 0.01) and IVC (P = 0.005) rims and no increase in aortic or AVV rims. No episodes of erosion occurred. CONCLUSIONS: ASDs in young children are not central in the septum, but proximate to the aorta. After ASO, the device remains in close proximity to the aorta. With somatic growth, the septum grows asymmetrically, and device position relative to the aorta is constant. Our study was not powered to detect rare serious adverse events such as erosion, but aortic rims were consistently zero and yet no events occurred.

Prevalence, predictors, and outcomes of cardiorenal syndrome in children with dilated cardiomyopathy: a report from the Pediatric Cardiomyopathy Registry.

BACKGROUND: The association of cardiorenal syndrome (CRS) with mortality in children with dilated cardiomyopathy (DCM) is unknown. METHODS: With a modified Schwartz formula, we estimated glomerular filtration rates (eGFR) for children ≥1 year of age with DCM enrolled in the Pediatric Cardiomyopathy Registry at the time of DCM diagnosis and annually thereafter. CRS was defined as an eGFR of <90 mL/min/1.73 m(2). Children with and without CRS were compared on survival and serum creatinine concentrations (SCr). The association between eGFR and echocardiographic measures was assessed with linear mixed-effects regression models. RESULTS: Of 285 eligible children with DCM diagnosed at ≥1 year of age, 93 were evaluable. CRS was identified in 57 of these 93 children (61.3%). Mean (standard deviation) eGFR was 62.0 (22.6) mL/min/1.73 m(2) for children with CRS and 108.0 (14.0) for those without (P < 0.001); median SCr concentrations were 0.9 and 0.5 mg/dL, respectively (P < 0.001). The mortality hazard ratio of children with CRS versus those with no CRS was 2.4 (95% confidence interval 0.8-7.4). eGFR was positively correlated with measures of left ventricular function and negatively correlated with age. CONCLUSIONS: CRS in children newly diagnosed with DCM may be associated with higher 5-year mortality. Children with DCM, especially those with impaired left ventricular function, should be monitored for renal disease.

Stenotrophomonas maltophilia infection among young children in a cardiac intensive care unit: a single institution experience.

Stenotrophomonas maltophilia can present as bacteremia, respiratory tract infection, urinary tract infection, soft tissue and wound infections, bone and joint infections, meningitis, and endocarditis especially in immunosuppressed patients and those with underlying medical conditions. The incidence and impact of S. maltophilia in young children with heart disease are poorly defined. A single center retrospective observational study was conducted in infants <180 days of age with positive S. maltophilia cultures over a period of 5 years. The overall incidence for S. maltophilia infection was 0.8 % (n = 32/3656). Among 32 identified infants, there were 47 episodes of S. maltophilia infection 66 % of infants had prior exposure to broad spectrum antibiotics. 97 % of positive isolates were susceptible to trimethoprim/sulfamethoxazole and 91 % to levofloxacin as well as ticarcillin/clavulanate. Ventilator-free days and absolute lymphocyte count prior to acquiring infection were significantly lower in non-survivors than in survivors. 100 % of survivors had clearance of positive cultures compared to 50 % in non-survivors (p < 0.05). The crude all-cause mortality rate was 37.5 %. All non-survivors had increased length of ICU stay and duration of mechanical ventilation and had delayed clearance of infection and required longer duration of treatment.

The FLUSH study--flush the line and ultrasound the heart: ultrasonographic confirmation of central femoral venous line placement.

STUDY OBJECTIVE: Inadvertent arterial placement of a femoral venous catheter may result in serious morbidity, including limb necrosis. The Flush the Line and Ultrasound the Heart (FLUSH) test is visualization of the heart by a subxiphoid ultrasonic view while the central catheter is flushed with agitated saline solution. We wish to determine whether the FLUSH test can verify proper femoral venous line placement. METHODS: We prospectively studied a convenience sample of children undergoing cardiac catheterization, for whom both femoral venous and arterial access were part of their standard care. The cardiologist flushed manually agitated saline solution through each catheter in randomized sequence while the blinded physician sonographer recorded the presence or absence of right atrial opacification. We calculated the sensitivity and specificity of the FLUSH test relative to our reference standard, the cardiologist's fluoroscopic visualization of catheter wire placement. RESULTS: Of the 51 subjects enrolled, the FLUSH test was 100% sensitive (95% confidence interval 95% to 100%) and 90.3% specific (95% confidence interval 81% to 96%) in confirming femoral catheter placement. In no case was an arterial flush misidentified as a femoral flush. The interrater reliability of the test was strong: κ 0.82 for all images and 0.9 for those of good quality. CONCLUSION: The FLUSH test is simple and reliable, and appears to accurately confirm femoral venous line placement.

Role for immune monitoring to tailor induction prophylaxis in pediatric heart recipients.

UNLABELLED: rATG is used for HTx induction but is costly and associated with infection and PTLD. HYPOTHESIS: Tailoring rATG induction with CD3 monitoring results in less infection, reduced costs, and similar rejection. Retrospective review of HTx recipients receiving rATG induction. Control cases received "usual" rATG dosing (1.5 mg/kg/day typically × 5 days). Starting in October 2009, absolute CD3 monitoring (target <25 cells/mm(3) ) guided rATG dosing (study cases). Outcomes included first-year incidence of infection/rejection, direct costs of therapy, and incidence of PTLD/death. Study cases (n = 32) received fewer doses of rATG (median 4 vs. 5, p < 0.001) and less total rATG (median 3.2 vs. 7.4 mg/kg, p < 0.001) compared with controls (n = 17). There was no difference in incidence of infection, rejection, or patient survival during the first year post-HTx. There was one early death in both groups and one late case of PTLD in the control group. Drug savings were significant (median drug cost per patient $2718 vs. $4756, p < 0.001). CD3-tailored rATG induction in HTx recipients is associated with reduced drug costs and similar rates of rejection/infection. Longer follow-up will determine whether extended benefits are associated with this induction monitoring strategy.

Mortality and Heart Transplantation After Hybrid Palliation of Hypoplastic Left Heart Syndrome: A Systematic Review and Meta-Analysis.

BACKGROUND: Newborns with hypoplastic left heart syndrome (HLHS) who are considered at increased risk for death following Norwood/Sano surgery often undergo hybrid palliation (HP) as initial surgery. We aimed to compile the HP experience in HLHS and its variants and assess the rates of, and risk factors for, death and heart transplantation. METHODS: CINAHL, CINAHL PLUS, PubMed/MEDLINE, and SCOPUS were systematically searched for HP outcome studies of death or heart transplantation in HLHS between 1998 and 2022. Pooled incidence was estimated, and potential risk factors were identified using random-effects meta-analysis and reconstructed time-to-event data from Kaplan-Meier curves. RESULTS: Thirty-three publications were included in our review. Overall, of 1,162 patients 417 died and 57 underwent heart transplantation, resulting in a combined outcome of 40.7%, (474/1,162). There was a trend toward decreasing mortality risk across the stages of palliation. Pooled mortality between HP and comprehensive stage 2 palliation was 25%, after stage 2 up to Fontan palliation was 16%, and 6% post-Fontan. The incidence of death or heart transplantation was higher in high-risk patients-43% died and 10% received heart transplantation. CONCLUSION: Our systematic review and meta-analysis found high rates of death or heart transplantation in HP of HLHS patients between HP and Fontan surgeries. All patients should be closely followed during the initial interstage period, which is associated with the highest hazard. Prospective studies on appropriate patient selection, indications, and / or alternatives, as well as refining HP strategies for managing newborns with HLHS are needed to improve outcomes.

Cardiac allograft vasculopathy in pediatric heart transplant recipients does early-onset portend a worse prognosis?

PURPOSE: We sought to evaluate the association between timing of cardiac allograft vasculopathy (CAV) occurrence post-heart transplant (HT) with graft survival and progression of CAV severity in pediatric HT recipients. METHODS: Data from the Pediatric Heart Transplant Society for pediatric (<18 years old) HT recipients between 1993-2019 with available angiographic data were obtained (N = 5,075). The timing of CAV diagnosis (<3; 3-<5; 5-<10; and ≥10 years post-HT) and severity of disease at each assessment (CAV 1-3) was determined. Associations between CAV timing, graft survival, and CAV progression were evaluated using Kaplan-Meier survival curves, multivariable COX proportional hazard regression analyses, and competing risk analyses. RESULTS: Over a median follow-up period of 4.1 (IQR 1.3-8.3) years, CAV was identified in 17% (885/5,075), 28% (252/885) of which were early-onset CAV. Compared with late onset CAV ≥10 years post-HT, patients with early CAV were older at the time of transplant (8.3 ± 6.2 vs. 3.8 ± 4.8 years, p < .0001). While the five-year graft-survival in the ≥10-year group (79.2%, p = 0.03) was significantly higher than the <3, 3-<5, and 5-<10 years post-HT groups (65.0%-67%) (p = 0.03), overall post-CAV graft survival was not significantly different across the CAV time-points. CAV disease progression did not vary with CAV timing post-HT, with an overall five-year freedom from CAV ≥2 of 75.4% (73.1%-77.6%). CONCLUSION: Later onset CAV (≥10-years post-HT) was associated with improved five-year graft survival compared with CAV onset at earlier time-points, but similar and poor long-term outcomes. CAV timing post-HT was not associated with progression of CAV disease severity.