About
71
Publications
3,670
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
730
Citations
Introduction
Current institution
Additional affiliations
July 2011 - April 2016
July 2011 - present
January 2009 - present
Publications
Publications (71)
Purpose
A recent multi-center study (CTOT-04) reported similar first year outcomes in children with CDC T-cell crossmatch (XM) + and XM- heart transplant (HT) but was underpowered and had only 11 children in the CDC+ HT group. We assessed the association of donor specific T-cell CDC and Flow XM HT with the risk of rejection and allograft loss in US...
Purpose
The TEAMMATE Trial is studying everolimus (EVL) with low-dose tacrolimus (LDTAC) vs. standard tacrolimus (TAC) with mycophenolate (MMF) in a randomized trial in children enrolled at 6 months post-heart transplant. Since therapeutic levels are correlated with lower rejection rates, we sought to describe the immunosuppressant drug level monit...
Purpose
Currently there are no-FDA approved immunosuppressants specific to pediatric heart transplantation (HT). In recent years, everolimus (EVL) has emerged as an alternative to tacrolimus (TAC) as a primary immunosuppressant to prevent rejection that may also prevent kidney and coronary disease. However, the two regimens have never been evaluate...
Purpose
The use of bivalirudin has increased dramatically for primary thromboprophylaxis in pediatric paracorporeal ventricular assist device (VAD) support with limited data on optimal monitoring of effect. Partial thromboplastin time (aPTT) is commonly used for monitoring of bivalirudin, but can be impacted by line heparin, variability in assays a...
Purpose
Currently there are no-FDA approved immunosuppressants specific to pediatric heart transplantation (HT). In recent years, everolimus (EVL) has emerged as an alternative to tacrolimus (TAC) as a primary immunosuppressant to prevent rejection that may also prevent kidney and coronary disease. However, the two regimens have never been evaluate...
Despite increasing legalization and use of marijuana, there is no consensus among pediatric heart transplant institutions or providers regarding users' eligibility for cardiac transplant. We sent a survey to pediatric and ACHD transplant providers (physicians, surgeons, transplant coordinators, and pharmacists) assessing their current institution's...
Background:
Two or more early rejections (<1 year) or any late acute rejection (>1 year) have been associated with coronary artery vasculopathy (CAV) in pediatric heart transplant (HT) recipients. We hypothesized that clinical rejection, defined by concurrent new-onset heart failure or left ventricular systolic dysfunction is more strongly associa...
Purpose
Pulmonary arterial catheters (PAC) provide real-time hemodynamic data that has been used to tailor ICU therapies, aid in surgical decision making in adults with ADHF and in predicting right-heart failure (RHF) in adults undergoing LVAD evaluation. Approximately 1/3 of patients develop RVF after LVAD insertion. Patients who required rescue R...
Background
Heart failure results in significant morbidity and mortality for young children with hypoplastic left heart syndrome (HLHS) following the Norwood procedure.
Methods
We studied subjects enrolled in the prospective Single Ventricle Reconstruction (SVR) trial who survived to hospital discharge after the Norwood operation and were followed...
Clinical practice variations are a barrier to the study of pediatric heart transplants and coordination of multicenter RCTs in this patient population. We surveyed centers to describe practice patterns, understand areas of variation, and willingness to modify protocol. Pediatric heart transplant centers were identified, and one survey was completed...
Mechanical circulatory support in the form of ventricular assist devices (VADs) in children has undergone rapid growth in the last decade. With expansion of device options available for larger children and adolescents, the field of outpatient VAD support has flourished, with many programs unprepared for the clinical, programmatic, and administrativ...
Background:
There is inadequate power to perform a valid clinical trial in pediatric heart transplantation (HT) using a conventional end-point, because the disease is rare and hard end-points, such as death or graft loss, are infrequent. We sought to develop and validate a surrogate end-point involving the cumulative burden of post-transplant comp...
A 2-year-old male presented following several weeks of increasing lethargy, poor growth, and difficulty breathing. He also had a mild lactic acidosis (plasma lactate, 2.1 mmol/L; reference interval: 0.9–1.2 mmol/L). As part of the investigation into his labored breathing, an echocardiogram was performed, which revealed markedly depressed left ventr...
Endomyocardial biopsy (EMB) is a common procedure used to aid in the diagnosis, prognosis and treatment of suspected pediatric cardiomyopathy. In suspected cardiomyopathy, no multicenter experience has previously reported on the safety and utility of EMBs. Retrospectively, adverse event (AE) and patient and procedural characteristics were obtained...
Background:
Cardiac allograft vasculopathy (CAV) is the leading cause of chronic allograft loss after pediatric heart transplantation. We hypothesized that biomarkers of endothelial injury and repair would predict CAV development in pediatric heart transplant recipients.
Methods:
Blood was collected from pediatric heart transplant recipients at...
Background:
Cardiac allograft vasculopathy (CAV) is a major cause of mortality after cardiac transplantation. High-density lipoprotein (HDL) cholesterol efflux capacity (CEC) is inversely associated with coronary artery disease. In 2 independent studies, we tested the hypothesis that reduced CEC is associated with mortality and disease progression...
Background: Quality measurement has become an integral part of adult heart failure (HF) practice and has been shown to improve patient outcomes. Currently there are no widely used quality measures (QM) in pediatric HF practice. We sought to develop consensus on QM at five large pediatric HF centers despite recognized limitations of their applicatio...
The National Organ Transplant Act stipulates that deceased donor organs should be justly and wisely allocated based on sound medical criteria. Allocation schemes are consistent across the country, and specific policies are publicly vetted. Patient selection criteria are largely in the hands of individual organ transplant programs, and consistent st...
Heart transplantation offers excellent survival benefit to children with end-stage heart failure. With its success, the number of potential recipients continues to exceed the number of available donors. Developing strategies to safely increase donor utilisation is crucial to decreasing wait-list mortality. A new paediatric heart allocation policy i...
In the United States alone, ∼14,000 children are hospitalised annually with acute heart failure. The science and art of caring for these patients continues to evolve. The International Pediatric Heart Failure Summit of Johns Hopkins All Children's Heart Institute was held on February 4 and 5, 2015. The 2015 International Pediatric Heart Failure Sum...
Identification of biomarkers that assess posttransplant risk is needed to improve long-term outcomes following heart transplantation. The Clinical Trials in Organ Transplantation (CTOT)-05 protocol was an observational, multicenter, cohort study of 200 heart transplant recipients followed for the first posttransplant year. The primary endpoint was...
Background: Coronary allograft vasculopathy (CAV) is an important cause of mortality after cardiac transplantation. High density lipoprotein (HDL) cholesterol efflux capacity has been inversely associated with coronary artery disease and is impaired in cardiac transplant recipients. We performed a single center case-cohort study to test the hypothe...
Advances in therapeutics have dramatically improved short-term graft survival, but the incidence of chronic rejection has not changed in the past 20 years. New insights into mechanism are sorely needed at this time and it is hoped that the development of predictive biomarkers will pave the way for the emergence of preventative therapeutics. In this...
Heart transplantation remains a lifesaving therapy for adults and children with end-stage heart disease. Since the first heart transplant was performed in 1967, advances in peri-operative care and long term immunosuppression have dramatically improved post-transplant outcomes (1). Currently, adult recipients can expect a median allograft survival o...
Positron emission tomography (PET) has the potential to be a specific, sensitive and quantitative diagnostic test for transplant rejection. To test this hypothesis, we evaluated F-labeled fluorodeoxyglucose ([F]FDG) and N-labeled ammonia ([N]NH3) small animal PET imaging in a well-established murine cardiac rejection model.
Heterotopic transplants...
Sensitization to HLA is a risk factor for adverse outcomes after heart transplantation. Requiring a negative prospective CM results in longer waiting times and increased waitlist mortality. We report outcomes in a cohort of sensitized children who underwent transplant despite a positive CDC CM+ using a protocol of antibody depletion at time of tran...
Purpose
Recent clinical experience suggests that heart transplant (HT) waiting times have increased for smaller children in the US. Limited data are available on actual trends in median waiting times for this population. We sought to describe median wait-times over the past 10 yrs for children between 10 and 25 kilograms at listing.
Methods and Ma...
Purpose Pediatric ventricular assist device (VAD) utilization has purportedly surged in the US in recent years. Accurate information regarding the type and frequency of devices currently used in children is limited. We sought to describe overall trends in pediatric VAD utilization as a bridge to heart transplant (HT) in the current era. Methods and...
Pediatric centers vary widely in their tendency to implant ventricular assist devices (VAD) in children with dilated cardiomyopathy (DCM) awaiting heart transplant (HT). The magnitude of this variability is unknown. We sought to describe center variability in pediatric VAD utilization and to determine whether higher VAD utilization is associated wi...
As pediatric VAD use in the US has grown, wait-list mortality for children listed for heart transplant (HT) has decreased. It is unclear whether this decrease applies to children at highest risk of waitlist mortality, specifically children supported on ECMO or a ventilator at listing.Methods and MaterialsAll patients <18 yrs of age listed for HT fr...
Studies suggest VADs may increase HLA sensitization in children waitlisted for heart transplant (HT). It is unknown how much sensitization is attributable to routine VAD use because of confounding factors such as previous surgeries and race. We sought to estimate the degree of sensitization attributable to VAD use by focusing our analysis on childr...
Cardiac allograft vasculopathy (CAV), the major cause of late allograft loss after cardiac transplantation, results from donor-directed cellular and humoral alloimmune responses. Graft vascular endothelial cells (EC) are primary targets of these destructive responses, suggesting that factors associated with endothelial injury and repair could serve...
Background: The exercise capacity of pts who have had Fontan surgery is often depressed. We hypothesized that an inability to reduce pulmonary vascular resistance appropriately during exercise contributes to this exercise intolerance, and that administration of an effective pulmonary vasodilator would improve exercise function after Fontan. Purpose...
In this review, we discuss how changes in the intragraft microenvironment serve to promote or sustain the development of chronic allograft rejection. We propose two key elements within the microenvironment that contribute to the rejection process. The first is endothelial cell proliferation and angiogenesis that serve to create abnormal microvascul...
No prior reports documenting the safety and diagnostic yield of cardiac catheterization and endomyocardial biopsy (EMB) in heart transplant recipients include multicenter data.
Data on the safety and diagnostic yield of EMB procedures performed in heart transplant recipients were recorded in the Congenital Cardiac Catheterization Outcomes Project d...
Sudden death is a well-recognized complication of heart transplantation. Little is known about the incidence and risk factors for sudden death after transplant in children. The purpose of this study was to determine the incidence of and risk factors for sudden death.
This retrospective multicenter cohort study used the Pediatric Heart Transplant St...
Hematopoietic SCT (HSCT) is a life-saving therapy in children, but has been associated with heart failure. Little is known about subclinical changes in cardiac function. We examined changes in systolic and diastolic function from pre- to 1-year post HSCT by echocardiography. All patients (n=74, 61% men, median age 9.1 years, mean left-ventricular (...
Patients presenting with thrombocytosis require thorough clinical and laboratory evaluation to determine whether they suffer from essential thrombocythemia or another myeloproliferative disorder. This distinction becomes increasingly relevant as targeted agents become available to treat specific myeloproliferative diseases. Cytogenetic testing play...
