B‐type natriuretic peptide trends after pediatric heart transplantation

BNP is increasingly utilized in the management of pediatric HT recipients. Performing a retrospective single‐center chart review, we sought to describe BNP changes during the first year after HT and identify factors that affect its trend. After exclusion for rejection, 316 BNP levels from 50 patients were evaluated. BNP underwent an exponential decline 120 days after HT followed by a plateau. Log₁₀BNP decline strongly correlated with time (r = ?0.70, p < 0.0001). Initial BNP was less in pretransplant VAD (p = 0.0016) and lower post‐HT inotrope use (p = 0.0043). Infant recipients, IT >4 h, and those bridged medically were associated with higher plateau BNP. Multivariable logistic regression demonstrated IT >4 h independently predicted plateau BNP in the upper quartile (OR 7.1, p = 0.02). No significant change in BNP coincided with rejection (N = 6 patients) without severe hemodynamic compromise. BNP correlated modestly with right atrial pressure (r = 0.4652, p < 0.0001) and pulmonary capillary wedge pressure (r = 0.2660, p < 0.001), but poorly with echocardiogram (r = ?0.18, p = 0.003). Trending BNP could help provide insight into how the graft recovers after HT and IT >4 h independently predicted higher plateau BNP and may reflect subtle changes in graft performance.     

Choledochal cyst in two pediatric heart transplant patients

Abstract:  Choledochal cyst is a relatively uncommon entity in Western countries. No reports of choledochal cyst in heart transplant patients have been reported to date. We report two cases of choledochal cyst in pediatric heart transplant recipients, one with post-transplant lymphoproliferative disorder (PTLD) within the cyst. The first patient had abdominal pain, increased liver enzymes and was seropositve for Epstein-Barr virus. A choledochal cyst with PTLD was removed 4 years after heart transplantation. The second patient presented 14 years after heart transplantation with a choledochal cyst that was excised for severe abdominal pain. This previously unreported association between choledochal cysts in conjunction with PTLD and heart transplantation is interesting and a possible common pathogenesis is proposed. The management and alternative treatments were briefly noted. We recommend an aggressive treatment for patients with suspected choledochal cyst after heart transplantation because of the increased potential for malignant transformation.     

Pediatric heart transplant from an incompletely treated influenza A‐positive donor

There is a shortage of pediatric donor hearts for waitlisted children, and yet nearly 50% of organs offered are not transplanted. Donor quality is often cited as a reason for declining organs offered from donors infected with influenza, presumably due to concern about disease transmission at transplant leading to severe disease. We previously described an excellent outcome after heart transplant from a donor infected with influenza B that had been treated with a complete course of oseltamivir. In this report, we describe a similar outcome after transplantation of an organ from an influenza A‐positive donor with symptomatic disease incompletely treated with oseltamivir. Due to the availability of effective antiviral treatment, we suggest that influenza A is also a manageable donor infection that need not preclude heart placement.     

Safety of mTOR inhibitor continuation in pediatric heart transplant recipients undergoing surgical procedures

mTOR inhibitors have been associated with SWC when used in the perioperative period. Limited literature is available to guide providers in managing chronic mTOR inhibitor use in the perioperative period, especially in the pediatric setting. The primary aim of this study was to describe the prevalence of SWC with mTOR inhibitor continuation during the perioperative period for major surgeries. Heart transplant recipients ≤25 years old at the time of primary heart transplant receiving sirolimus maintenance therapy during a surgical procedure and within the study period were included. Surgeries identified within the study period included otolaryngology procedures (46.2%), such as tonsillectomies with or without adenoidectomies, cardiac surgeries (30.8%) including a sternal revision, pulmonary vein repair, and pacemaker placement in two patients, orthopedic surgeries (15.4%) including a posterior spinal fusion and an Achilles tendon lengthening with ankle and subtalar joint release, and a neurosurgery (7.7%), which was a ventriculoperitoneal shunt revision. Thirteen surgical encounters were examined. One SWC was observed, an infected pacemaker requiring systemic antibiotics and removal of the device. The results of this study suggest that sirolimus may be continued in the perioperative period based on the low rate of SWC observed.     

Screening for rejection in symptomatic pediatric heart transplant recipients: the sensitivity of BNP

Abstract:  As the pediatric OHT population expands, there is increasing demand for convenient, yet sensitive screening techniques to identify children with acute rejection when they present to acute care facilities. In children, symptoms of acute rejection or other causes of graft dysfunction are often non-specific and can mimic other childhood illnesses. The aim of this study was to assess the utility of BNP as a biomarker to assist providers in clinical decision-making when evaluating symptomatic pediatric heart transplant patients. One hundred twenty-two urgent care and emergency room visits from 53 symptomatic pediatric OHT patients were retrospectively reviewed to evaluate the relationship between BNP levels, symptoms, and clinical diagnosis at these visits. An ROC curve was generated to determine the accuracy of BNP as a screening tool for acute rejection in this patient population. In this group of patients, a BNP value of >700 pg/mL was 100% sensitive and 92% specific for detecting allograft acute rejection (NPV of 100%). We concluded that BNP is a highly sensitive screening test for acute rejection in symptomatic pediatric heart transplant patients.     

Allosensitization does not alter post‐transplant outcomes in pediatric patients bridged to transplant with a ventricular assist device

Patients supported with a VAD are at increased risk for sensitization. We aimed to determine risk factors for sensitization as well as the impact of sensitization on post‐transplant outcomes. The UNOS database (January 2004–June 2014) was used to identify patients (≤18 yrs) supported with a durable VAD. Rates and degree of sensitization in the VAD cohort were calculated. Post‐transplant survival was determined comparing outcomes of sensitized vs. non‐sensitized patients. There were 3097 patients included in the study; 19% (n = 579) were bridged with a VAD. Of these, 41.8% were sensitized vs. 29.9% of the patients who were not bridged with a VAD (p < 0.001). VAD was an independent predictor of sensitization (OR 2.05 [1.63–2.57]; p < 0.001). There was no difference in sensitization based on device type (continuous vs. pulsatile flow, p = 0.990). Post‐transplant survival rates between the sensitized and non‐sensitized VAD patients were not different, including patients with a PRA >50% and VAD patients with a positive DSC (p = 0.280 and 0.160, respectively). In conclusion, pediatric VAD patients are more likely to be sensitized, but there was no difference in sensitization based on device type. In addition, sensitization does not appear to impact outcomes.     

Liver abnormalities and post‐transplant survival in pediatric Fontan patients

The impact of liver parenchymal abnormalities on survival post‐heart transplant remains unknown in pediatric Fontan patients. We assessed pediatric Fontan patients who underwent heart transplant and had documented pretransplant hepatic ultrasound (U/S) studies. Liver U/S findings were classified as normal (Group 1), mildly abnormal (Group 2, hepatomegaly/vascular congestion), or severely abnormal (Group 3, heterogeneous echotexture/nodularity). Among 30 study patients, 8 were classified as Group 1, 14 as Group 2, while 8 met Group 3 criteria. Pretransplant liver biochemistry and synthetic function were similar in all groups. Six Group 3 patients underwent liver biopsy; 4 demonstrated perisinusoidal or centrilobular fibrosis, and 2 had cirrhosis. Overall mortality was 30% (n = 9). Median follow‐up was 5 years (range, 0.25‐13 years). One‐year survival was similar among all 3 groups (P = .37), with a trend toward higher cumulative 5‐year survival in Group 1 (100%). The majority of pediatric Fontan patients who underwent heart transplant demonstrated abnormal preoperative liver ultrasound findings. Heterogeneous echotexture or nodularity detected on U/S frequently indicates underlying liver parenchymal abnormalities. The presence of severe liver abnormalities was not associated with higher early mortality post‐heart transplant in pediatric Fontan patients; however, late outcomes must be further elucidated.     

Educational and learning morbidity in pediatric heart transplant recipients: A pediatric heart transplant society study

Educational development is an important component of quality of life for children with heart transplant. Aims include determining prevalence of and risk factors for modified education placement in a large representative sample of pediatric heart transplant recipients. Participants included 1495 patients (age 6‐18 years) from the PHTS database. Data on education placement and clinical predictors were collected at listing and at 1 and 3 years post‐transplant. At listing, 88% of patients were in typical education placement, while 12% were in modified education. Males (P = .02), those with CHD (P < .0001), those with non‐private insurance (P < .0001), and those with longer hospital stay (P = .001) were more likely to be in a modified education placement at time of listing. Age, race, listing status, mechanical support, and waitlist time were not significantly associated with placement. The prevalence of typical education placement was similar (87% at 1‐year and 86% at 3‐year) post‐transplant. Predictors of modified education placement at 3‐year follow‐up included placement at listing (OR = 12.9 [95% CI 7.6‐21.9], P < .0001), non‐private insurance (OR = 2.0 [95% CI 1.3‐3.2], P = .001), CHD (OR = 1.8 [95% CI 1.1‐2.7, P = .01), history of post‐transplant infection (OR = 1.9 [95% CI 1.2‐2.9, P = .007), and number of post‐transplant infections (OR = 1.3 [95% CI 1.1‐1.5, P = .002). Among pediatric heart transplant recipients, males, those with non‐private insurance, those with CHD, and those who experience post‐transplant infections are at greatest risk for modified academic placement, which persists for several years post‐transplant and deserves targeted intervention.     

Vasoactive–inotropic score after pediatric heart transplant: A marker of adverse outcome

VIS, a quantitative index of pressor support, has been shown to be a predictor of morbidity and mortality in infants younger than six months who underwent CPB. Data on its prognostic utility following pediatric OHT are lacking. This study compared clinical outcomes in children with differential VIS after pediatric OHT. A retrospective cohort study of 51 consecutive heart transplants from 2004 to 2011 was performed at a pediatric tertiary care facility. Peak VIS was computed within initial 24 and 48 h after OHT and was weighted for peak dose and administration of any or all of six pressors. Patients with peak VIS ≥ 15 constituted high VIS group. Children who persistently required a higher magnitude of pressor support for the first 48 h after OHT, as reflected by high peak VIS, had significantly longer ICU stay (30.2 vs. 15.9 days, p = 0.01), pressor (11.4 vs. 6.8 days, p = 0.02) and ventilatory durations (12.4 vs. 5.9 days, p = 0.05), and higher rates of short‐term morbidities. Patients with longer CPB (213 vs. 153 min, p = 0.005) time have higher peak VIS. High peak VIS at 48 h is an effective, yet simple clinical marker for adverse outcomes in pediatric OHT recipients.     

Bone mineral status in pediatric heart transplant recipients: A retrospective observational study of an “at risk” cohort

Sachdeva R, Soora R, Bryant JC, Seibert JJ, Blaszak RT, Frazier EA. Bone mineral status in pediatric heart transplant recipients: A retrospective observational study of an “at risk” cohort.
Pediatr Transplantation 2010:14: 383–387. © 2009 John Wiley & Sons A/S. Abstract: There is a paucity of literature assessing the burden of bone loss in PHT recipients. We sought to describe the bone mineral status in PHT recipients by doing a retrospective medical record review of those who underwent evaluation of BMD when clinically indicated. Data collected included patient demographics, BMD evaluations, serum calcium, phosphorus, alkaline phosphatase, cumulative steroid dose, osseous complications and their management. Of 149 PHT recipients, 26 underwent BMD evaluation. This evaluation was done at a median of 3.4 yrs after PHT. There total serum calcium, phosphorus and alkaline phosphatase were similar at transplant and BMD study. The median BMD Z‐scores were: whole body ?0.09 (1.5 to ?5.13) and lumbar spine ?1.1 (1.5 to ?5.16). Bone loss (Z‐score 相似文献   

Low donor‐to‐recipient weight ratio does not negatively impact survival of pediatric heart transplant patients

Tang L, Du W, Delius RE, L’Ecuyer TJ, Zilberman MV. Low donor‐to‐recipient weight ratio does not negatively impact survival of pediatric heart transplant patients.
Pediatr Transplantation 2010: 14:741–745. © 2010 John Wiley & Sons A/S. Abstract: A major limitation to success in pediatric heart transplantation is donor organ shortage. While the use of allografts from donors larger than the recipient is accepted, the use of undersized donor grafts is generally discouraged. Using the UNOS database, we wanted to evaluate whether using smaller donor hearts affects the short‐ and long‐term survival of pediatric heart transplant patients. A retrospective analysis of data entered into the UNOS database from April 1994 to May 2008 was performed. Pediatric heart transplant recipients (ages 0–18 yr) with DRWR <2.0 were identified and divided into two groups: Low‐DRWR (<0.8) and Ideal‐DRWR (0.8–2.0). Patients’ demographics, pretransplant diagnoses, age at transplantation, severity of pretransplant condition, and rate of complications prior to hospital discharge after transplantation were noted. Fisher’s exact, chi‐square, and Wilcoxon rank sum tests were used to compare patients’ baseline characteristics. Kaplan–Meier curves and Cox proportional hazard regression were used to compare patients’ survival and to identify independent risk factors for outcomes. There were 3048 patients (204 with Low‐ and 2844 with Ideal‐DRWR). The Low‐ratio group patients were older (8.3 vs. 6.9 yr; p = 0.001), there was a slight male predominance in the Low‐DRWR group (p = 0.055). The Low‐DRWR group had longer transplant wait time than the Ideal‐DRWR group (97 vs. 85 days; p = 0.04). The groups did not differ in race, primary diagnoses, severity of pretransplant condition (medical urgency status, need for ventilation, inotropic support, ECMO, nitric oxide, or dialysis, the PVR for those with bi‐ventricular anatomy), or post‐transplant complications (length of stay, need for inotropic support, dialysis, and rate of infections). The Low‐DRWR patients had less episodes of acute rejection during the first‐post‐transplant month. Infants with DRWR 0.5–0.59 had lower 30‐day survival rate (p = 0.045). There was no difference in short‐ and long‐term survival between the patients with DRWR 0.6–0.79 and DRWR 0.8–2.0. Use of smaller allografts (DRWR 0.6–0.8) has no negative impact on the short‐ and long‐term survival of pediatric heart transplant patients.     

Alemtuzumab (Campath‐1H) therapy for refractory rejections in pediatric heart transplant recipients

Despite substantial improvements in survival after pediatric heart transplantation, refractory rejection remains a major cause of morbidity and mortality. We have utilized ALE (Campath‐1H) in six consecutive patients with refractory rejection. These rejection episodes persisted despite conventional treatment, which included intravenous methylprednisolone, rituximab, immunoglobulin G, and antithymocyte globulin. In our series, after ALE therapy, LV SF increased from 22%±5% to 33%±5% (P=.01). However, in our series, ALE therapy neither led to persistent LV function recovery nor could it prevent subsequent antibody‐mediated rejection.     

Everolimus‐associated perianal ulcers in an eight‐month‐old heart transplant recipient

mTOR inhibitors have a wide spectrum of therapeutic applications in adults and children. Little is known, however, about serious adverse effects in children undergoing mTOR inhibitor therapy. Oral ulcers are common and sometimes severe, but no other gastrointestinal involvement has been reported so far. Here we present a case of everolimus‐associated perianal ulcers in an eight‐month‐old infant, 3 months after heart transplantation, which necessitated the drug's discontinuation. In a thorough series of diagnostic tests, we identified no other cause for the progressive perianal ulceration. The recognition and appropriate management of mTOR inhibitors' adverse effects in pediatric patients are essential and remain challenging.     

Donors' characteristics and impact on outcomes in pediatric heart transplant recipients

Organ availability and acceptability limit pediatric HTx. What characteristics define an unacceptable or high‐risk pediatric donor remains unclear. The purpose of this study was to characterize a large cohort of pediatric donors and determine the donor risk factors, including cumulative risk, that affect recipient survival. Data from the PHTS, a prospective multicenter study, were used to examine the impact of donor factors on the outcomes of patients listed <18 yr of age who received a HTx between 1993 and 2009. Donor data were available for 3149 of 3156 HTx (99.8%). Donor cause of death, need for inotropes, or CPR did not affect survival outcomes (p = 0.05). Ischemic time also did not have an impact on overall recipient survival; however, longer ischemic times negatively impacted one‐yr post‐transplant survival (p < 0.0001). There was no impact of cumulative risk factors on survival (p = 0.8). Although used in a minority of cases, hormonal therapy in the donor positively impacted survival (p = 0.03). In multivariate analysis, the only donor factor associated with decreased survival was smaller donor BSA, the other factors being related to the recipient characteristics. When analyzed by recipient age, there were no donor‐related factors that affected survival for those who received a transplant at <6 months of age. Longer ischemic time (p < 0.0001) and greater age difference between the recipient and donor (p = 0.0098) were donor‐related factors impacting early‐phase survival for recipients who received a graft at ≥10 yr of age. Factors perceived to define a marginal or high‐risk pediatric heart donor including inotrope use, CPR and donor cause of death may have less impact on outcomes than previously thought. Longer ischemic times did impact one yr, but not overall survival, and this impact was much greater with older donors. Parameters for accepting a donor heart can potentially be expanded, especially in the infant age group, but strong consideration should always be given to the interaction between ischemic time and donor age.     

The effect of MMF dose and trough levels on adverse effects in pediatric heart transplant recipients

Limited pharmacokinetic and safety data exist for MMF in pediatric HTR. Previously targeted MPA‐TL are 1.5–3.0 μg/mL. The objective of this study was to assess the outcomes targeting MPA‐TL of 0.8–2.0 μg/mL in pediatric HTR. MPA‐TL were retrospectively collected 2–12 months post‐transplant. Acute rejection, infection, leukopenia, and GI complaints were then correlated with MPA‐TL. A total of 355 MPA‐TL from 22 HTR were included. Median age was 2.5 yr. Primary indication for transplant was dilated cardiomyopathy (64%). Mean MPA‐TL was 1.7 ± 0.9 μg/mL. African American patients received significantly higher doses (702 ± 235 mg/m²) compared with other races (p = 0.035). Leukopenia was less common in patients with SUB MPA vs. others (p = 0.01). MMF was discontinued for GI complaints in one patient and leukopenia in two patients. One SUB patient had acute rejection, and one SUP patient had infection. One‐yr survival was 100%. Targeting a lower range for MPA‐TL was not associated with significant rejection or infection. Despite lower MPA‐TL, MMF was discontinued in 3/22 patients for adverse effects.     

Paroxysmal complete atrioventricular block in pediatric heart transplant recipients following cardiac catheterization: A case series

Late‐onset paroxysmal AVB has been described as a rare complication after HT and has been associated with AR or CAV. We describe 4 pediatric HT recipients who developed paroxysmal AVB hours after routine cardiac catheterization in the absence of AR, CAV, or underlying conduction system disease. Four pediatric HT recipients who were >1 year post‐transplant had episodes of paroxysmal AVB hours after surveillance cardiac catheterization with EMB. Telemetry demonstrated high‐grade block, ranging from 2:1 AVB to complete AVB without ventricular escape for several seconds. None of the patients had significant AR or rapidly progressive CAV. Supplemental testing did not reveal underlying conduction system disease. Three of the 4 patients received permanent pacemakers, although subsequent interrogations showed minimal ventricular pacing. These pediatric HT recipients had paroxysmal AVB hours after cardiac catheterization in the absence of significant AR, CAV, or underlying conduction system disease. Subsequent pacemaker interrogations showed minimal ventricular pacing, suggesting these were isolated episodes. These cases suggest that mechanisms in addition to AR and CAV may cause paroxysmal AVB in pediatric HT recipients, warranting further investigation.