Obesity and dyslipidemia predict cardiac allograft vasculopathy and graft loss in children and adolescents post-heart transplant: A PHTS multi-institutional analysis.

BACKGROUND: Obesity and dyslipidemia afflict children of all ages. We explored the prevalence of obesity and dyslipidemia in pediatric heart transplant (HT) recipients and its effects on cardiac allograft vasculopathy (CAV) and survival. METHODS: This study included primary HT recipients (≤18 years) transplanted between 01/1996 and 12/2018 included in the Pediatric Heart Transplant Society database. Obesity was categorized according to WHO/CDC guidelines and dyslipidemia according to the National Cholesterol Education Program. Kaplan-Meier analyses for CAV and graft loss stratified for BMI and lipid panels were generated and risk factors identified using multivariate analyses. RESULTS: Among 6291 HT patients (median age [range] at HT = 4.3 [0.6-12.8] years; 45% Female; 68% White), 56% had a normal BMI at HT. Obese patients at HT had an increased risk for graft loss (HR 1.19, 95% CI 1.01-1.4, p = .04). Poor total cholesterol (TC), LDL-C, and TG were associated with the risk of both CAV (HR 1.79, p < .0001; HR 1.65, p = .0015; HR 1.53, p < .0001, respectively) and graft loss (HR 1.58, p = .0008; HR 1.22, p = .04; HR 1.43, p = .0007, respectively). CONCLUSIONS: Pediatric patients who are obese at the time of HT and dyslipidemic at 1 year post-HT are at an increased risk for CAV and graft loss. Preventative interventions may reduce morbidity and mortality among this cohort.

Clinical approach to antibody-mediated rejection from the pediatric heart transplant society.

OBJECTIVE: This document is designed to outline the definition, pathogenesis, diagnostic modalities and therapeutic measures to treat antibody-mediated rejection in children postheart transplant METHODS: Literature review was conducted by a Pediatric Heart Transplant Society (PHTS) working group to identify existing pediatric and adult studies on antibody-mediated rejection (AMR). In addition, the centers participating in PHTS were asked to submit their approach to diagnosis and management of pediatric AMR. This document synthesizes information gathered from both these sources to highlight a practical approach to diagnosing and managing a child with AMR postheart transplant. This document may not represent the practice at all centers in the PHTS and serves as a starting point to understand an approach to this clinical scenario.

Identification of patient variables that are associated with ventricular end-diastolic pressure before the bidirectional Glenn operation.

INTRODUCTION: Systemic ventricular end-diastolic pressure is important in patients with single ventricle heart disease. Predictors of an elevated systemic ventricular end-diastolic pressure prior to bidirectional Glenn operation have been incompletely identified. METHODS: All patients who underwent bidirectional Glenn operation operation at our centre between January 2007 and March 2017 were retrospectively identified and patient variables were extracted. For patients who had undergone Fontan operation at the time of this study, post-Fontan patient variables were also extracted. RESULTS: One-hundred patients were included with a median age at pre-bidirectional Glenn operation catheterisation of 4.5 months. In total, 71 (71%) patients had a systemic right ventricle. At the pre-bidirectional Glenn operation catheterisation, the mean systemic ventricular end-diastolic pressure was higher amongst those with systemic right ventricle compared to left ventricle (9.1 mmHg ± 2.1 versus 7.7 ± 2.7 mmHg, p < 0.01). On univariate analysis, pre-bidirectional Glenn operation systemic ventricular end-diastolic pressure was positively associated with the presence of a systemic right ventricle (p < 0.01), history of recoarctation (p = 0.03), history of Norwood operation (p = 0.04), and ventricular systolic pressure (p < 0.01). On multivariate analysis, systemic ventricular end-diastolic pressure was positively associated with the presence of a systemic right ventricle (p < 0.01) and ventricular systolic pressure (p < 0.01). Amongst those who had undergone Fontan operation at the time of study (n = 49), those with a higher pre-bidirectional Glenn operation systemic ventricular end-diastolic pressure were more likely to have experienced death, transplantation, or listed for transplantation (p = 0.02) and more likely to have had heart failure symptoms (p = 0.04) at a mean time from Fontan of 5.2 years ± 1.3. CONCLUSIONS: In patients undergoing bidirectional Glenn operation operation, the volume-loaded, pre-bidirectional Glenn operation state may expose diastolic dysfunction that has prognostic value.

Rapid resolution of colitis related to immunosuppressive medication after infliximab administration.

Immunosuppression is necessary after solid organ transplantation. The non-infectious side effects associated with many of these agents are not well understood. We report a case of colitis, most resembling inflammatory bowel disease, that persisted despite withdrawal of tacrolimus and mycophenolate mofetil and transition to alternative agents. The patient was treated for clostridium difficile without improvement. Endoscopic biopsies demonstrated non-specific inflammation without evidence of active infection. An extensive immunologic and oncologic workup was negative. Ultimately, we trialed the administration of infliximab, a monoclonal antibody that inhibits TNF-alpha receptors that is commonly used in the treatment of inflammatory bowel disease. With infliximab treatment, the patient experienced rapid resolution of his disease and has remained in remission.

A Congenital Portosystemic Shunt in a Child With Heterotaxy, Situs Inversus, Polysplenia, and Interrupted Inferior Vena Cava With Azygous Continuation.

Congenital portosystemic shunts are rare vascular malformations in which portal venous blood from the intestines and spleen bypasses the liver and diverts directly into the systemic circulation through abnormal vessels. We report a case of a 4-year-old girl with heterotaxy syndrome, polysplenia, and situs inversus presenting with persistent hypoxemia who was found to have pulmonary arteriovenous malformations (PAVMs) and hypoxemia secondary to a congenital portosystemic shunt. Management of this patient's PAVMs involved endovascular occlusion of the portosystemic shunt with subsequent resolution of hypoxemia. PAVMs secondary to extrahepatic portosystemic shunt should be explored as a cause of progressive cyanosis in children with heterotaxy, polysplenia, and interrupted inferior vena cava with azygous continuation.

Cardiac allograft vasculopathy and graft failure in pediatric heart transplant recipients after rejection with severe hemodynamic compromise.

BACKGROUND: Rejection with severe hemodynamic compromise (RSHC) carries a mortality risk approaching 50%. We aimed to identify current risk factors for RSHC and predictors of graft failure after RSHC. METHODS: Data from 3,259 heart transplant (HT) recipients between January 2005 and December 2015 in the Pediatric Heart Transplant Study (PHTS) were analyzed. Predictors for RSHC and outcome after RSHC were sought. Time to RSHC was analyzed using the Cox proportional hazards regression model. Cardiac allograft vasculopathy (CAV) after HT and CAV after RSHC were analyzed as time-dependent covariates. Timing of RSHC was analyzed as occurring before and after 4 years after RSHC. RESULTS: There were 309 patients (9.5%) with ≥ 1 RSHC episodes. In 143 patients with RSHC, the first episode was within 1 year after HT. Independent risk factors for RSHC were age 1 to 5 years at HT (hazard ratio [HR], 1.51; 95% confidence interval [CI], 1.04-2.18), age > 10 years at HT (HR, 1.83; 95% CI, 1.29-2.60), black race (HR, 1.64; 95% CI, 1.25-2.15), prior cardiac surgery (HR, 1.55; 95% CI, 1.03-2.31), ventricular assist device support at HT (HR, 1.65; 95% CI, 1.18-2.29), maintenance steroids (HR, 1.39; 95% CI, 1.06-1.82), and recipient on inotropes, pressors, or thyroid hormones (HR, 1.45; 95% CI, 1.09-1.94). Graft survival at 5 years after RSHC was 45.7%. RSHC was a greater risk factor for earlier CAV (HR, 7.78; 95% CI, 5.82-10.40) than other rejection types (HR, 2.31; 95% CI, 1.79-3.00). Patients with late RSHC, after 1 year after RSHC had increased risk of graft loss 4 years after RSHC (HR, 7.12; 95% CI, 2.18-23.22). The 5-year graft survival after RSHC was 50.5% for early RSHC and 39.0% for late RSHC. CONCLUSIONS: Mortality after RSHC is high in the current treatment era. Many patient risk factors for RSHC cannot be modified, including age, race, prior cardiac surgery, and ventricular assist device support. After RSHC, CAV is the only predictor of graft failure. Patients who have late RSHC fare worse than those who have RSHC within the first year after HT.

Successful Salvage of an Extracardiac Fontan in the Setting of Purulent Mediastinitis using Antibiotic-Impregnated Beads.

Post-cardiotomy mediastinitis is an especially serious complication after the implantation of prosthetic vascular grafts. Standard of care is irrigation, debridement, and removal of all prosthetic material present in the surgical field. The use of antibiotic impregnated beads at the site of infection has been reported in the salvage of vascular grafts in the adult population. We present the case of a 3-year-old child with hypoplastic left heart syndrome who developed mediastinitis following the Fontan operation. In a nontraditional approach, the Fontan conduit, which was surrounded by gross purulence, was successfully salvaged with the adjunctive use of vancomycin-impregnated beads.

Congenitally corrected transposition.

Congenitally corrected transposition is a rare cardiac malformation characterized by the combination of discordant atrioventricular and ventriculo-arterial connections, usually accompanied by other cardiovascular malformations. Incidence has been reported to be around 1/33,000 live births, accounting for approximately 0.05% of congenital heart malformations. Associated malformations may include interventricular communications, obstructions of the outlet from the morphologically left ventricle, and anomalies of the tricuspid valve. The clinical picture and age of onset depend on the associated malformations, with bradycardia, a single loud second heart sound and a heart murmur being the most common manifestations. In the rare cases where there are no associated malformations, congenitally corrected transposition can lead to progressive atrioventricular valvar regurgitation and failure of the systemic ventricle. The diagnosis can also be made late in life when the patient presents with complete heart block or cardiac failure. The etiology of congenitally corrected transposition is currently unknown, and with an increase in incidence among families with previous cases of congenitally corrected transposition reported. Diagnosis can be made by fetal echocardiography, but is more commonly made postnatally with a combination of clinical signs and echocardiography. The anatomical delineation can be further assessed by magnetic resonance imaging and catheterization. The differential diagnosis is centred on the assessing if the patient is presenting with isolated malformations, or as part of a spectrum. Surgical management consists of repair of the associated malformations, or redirection of the systemic and pulmonary venous return associated with an arterial switch procedure, the so-called double switch approach. Prognosis is defined by the associated malformations, and on the timing and approach to palliative surgical care.