Usefulness of routine surveillance biopsies in children more than one year after orthotopic heart transplantation.

This retrospective study examines the usefulness of routine biopsies following the first year after transplant. This study found that routine biopsies detect few episodes of rejection in the first year after transplant and were less useful than nonroutine biopsies.

Long-term results of triple-drug-based immunosuppression in nonneonatal pediatric heart transplant recipients.

BACKGROUND: Few reports document long-term results of pediatric cardiac transplantation in which triple therapy (cyclosporine, azathioprine, and corticosteroids) was the mainstay of immunosuppression. This report details a single center's pediatric transplant experience and analyzes the relative contributions of selected pre/posttransplant risk factors on long-term morbidity and mortality. METHODS: Retrospective data were collected for all non-neonatal pediatric transplant recipients including: presenting diagnosis, cardiac hemodynamics (particularly pulmonary vascular resistance index), donor ischemic time, occurrence of postoperative infections, episodes of allograft rejection, incidence of posttransplant lymphoproliferative disease or coronary artery disease (CAD), and overall survival. Analysis of single variables and a Cox-proportional hazards model were utilized to determine the impact of pre/posttransplant risk factors on long-term survival. RESULTS: From 1984 to 1995, 64 patients (mean age, 8.3 years), 46 of whom had cardiomyopathy and 18 who had inoperable complex congenital heart disease, underwent cardiac transplantation and received triple-drug immunosuppression. Orthotopic transplantation was performed unless the pulmonary vascular resistance index remained >6 um2 (despite use of pulmonary vasodilator). One patient required heterotopic transplantation. Average donor ischemic time was 217 min. An average of 1.2 rejection episodes/patient occurred (average follow-up period: 50 months). No patient developed posttransplant lymphoproliferative disease, but 22 patients (34%) developed CAD. Overall survival was 80%, 60%, and 57% at 1, 5, and 10 years, respectively. Of outcome variables analyzed, rejection frequency was significantly increased in patients who subsequently developed CAD, but the presence of CAD was not significantly correlated with mortality. CONCLUSION: Triple-drug-based immunosuppressive maintenance therapy in pediatric heart transplant recipients results in good long-term graft survival.

Cardiac transplantation for pediatric patients. With inoperable congenital heart disease.

Recent studies have reported the expanding use of transplantation as the definitive option for pediatric patients with inoperable congenital heart disease. This study compares perioperative risk factors and outcomes in pediatric patients who received heart transplants for congenital heart disease with those in pediatric patients who received heart transplants for cardiomyopathy. Retrospective data collected on 40 consecutive pediatric patients undergoing cardiac transplantation from 1 January 1990 through 31 January 1995 provided the following results: 26 patients with cardiomyopathy (mean age, 7.6 years) and 14 patients with congenital heart disease (mean age, 7.2 years) underwent heart transplantation. Between groups, no significant difference was detected in waiting time for a donor heart (cardiomyopathy = 85 days, range = 2 to 409; congenital heart disease = 126 days, range = 9 to 396; P = NS); in donor/recipient weight ratio (1.27 +/- 0.34 vs 1.27 +/- 0.28, P = NS); or in ischemic times (209 +/- 92 minutes vs 248 +/- 70 minutes, P = NS). Cardiopulmonary bypass times accounted for the only significant difference (73 +/- 21 minutes vs 102 +/- 29 minutes, P = 0.003). No significant difference was found in the number of infection episodes, total days hospitalized, rejection episodes, or incidence of transplant coronary artery disease. Forty-month actuarial survival was 88% +/- 6% and 92% +/- 7% for cardiomyopathy and congenital heart disease transplant recipients, respectively (P = NS). We conclude that post-transplantation morbidity and mortality in patients with previous congenital heart disease are not significantly different from morbidity and mortality in patients with cardiomyopathy. Transplantation should be considered an acceptable therapeutic option for patients with congenital heart disease when surgical repair of the native heart is not possible.

Association of parvovirus B19 genome in children with myocarditis and cardiac allograft rejection: diagnosis using the polymerase chain reaction.

BACKGROUND: Inflammatory diseases of the heart, including myocarditis and cardiac transplant rejection, are important causes of morbidity and mortality in children. Although viral infection may be suspected in either of these clinical conditions, the definitive etiology is often difficult to ascertain. Furthermore, the histology is identical for both disorders. Coxsackievirus has long been considered the most common cause of viral myocarditis; however, we previously demonstrated by polymerase chain reaction (PCR) analysis that many different, and sometimes unexpected, viruses may be responsible for myocarditis and cardiac rejection. In this study, we describe the association of parvovirus genome identified through PCR analysis of cardiac tissue in the clinical setting of myocarditis and cardiac allograft rejection. METHODS AND RESULTS: Myocardial tissue from endomyocardial biopsy, explant, or autopsy was analyzed for parvovirus B19 using primers designed to amplify a 699-base pair PCR product from the VP1 gene region. Samples tested included those obtained from patients with suspected myocarditis (n=360) or transplant rejection (n=200) or control subjects (n=250). Parvoviral genome was identified through PCR in 9 patients (3 myocarditis; 6 transplant) and no control patients. Of the 3 patients with myocarditis, 1 presented with cardiac arrest leading to death, 1 developed dilated cardiomyopathy, and the other gradually improved. Four of the 6 transplant patients had evidence of significant rejection on the basis of endomyocardial biopsy histology. All transplant patients survived the infection. CONCLUSIONS: Parvovirus is associated with myocarditis in a small percentage of children and may be a potential contributor to cardiac transplant rejection. PCR may provide a rapid and sensitive method of diagnosis.

Outcomes among pediatric heart transplant recipients.

Postoperative cytomegalovirus prophylaxis with cytomegalovirus immunoglobulin or ganciclovir has decreased the incidence of cytomegalovirus disease in cytomegalovirus-negative recipients of cytomegalovirus-positive donor organs. In adults, these drugs have also been used to treat recipients who developed symptomatic cytomegalovirus disease. This report describes outcomes of predominantly cytomegalovirus-negative pediatric cardiac transplant recipients of cytomegalovirus-positive donor organs who received cytomegalovirus immunoglobulin plus ganciclovir as cytomegalovirus prophylaxis, as well as results of this combination therapy when used to treat cytomegalovirus disease. We reviewed the records of children who received donor hearts at our institution between 1989 and 1994. Cytomegalovirus-negative patients who received cytomegalovirus-positive donor organs were given prophylaxis consisting of ganciclovir (5 mg/kg every 12 hours for 14 days, followed by maintenance dosage of 5 to 6 mg/kg every day for 14 days) plus 7 scheduled cytomegalovirus immunoglobulin infusions. Cytomegalovirus infection was documented by culture, polymerase chain reaction, and cytomegalovirus immunoglobulin M seroconversion of a 4-fold or greater rise in cytomegalovirus immunoglobulin G titers. After infection, patients were diagnosed with cytomegalovirus disease when they developed clinical symptoms. These episodes were treated with cytomegalovirus immunoglobulin infusions plus ganciclovir (5 mg/kg every 12 hours) until symptoms resolved. Of 40 cardiac transplant recipients, 10 cytomegalovirus-negative and 9 cytomegalovirus-positive patients received cytomegalovirus-positive donor organs. Five patients (3 of whom were seronegative and had received dual-agent prophylaxis) developed cytomegalovirus disease, which resolved with dual-agent therapy. During an average 15-month follow-up period, no significant morbidity or mortality was attributable to cytomegalovirus disease. Post-transplant dual-therapy cytomegalovirus prophylaxis appears to be as safe and effective in children as in adults, when our results are compared with the published results of studies in adults. Dual-agent treatment eradicated symptoms among patients who developed cytomegalovirus disease. This regimen may allow safer use of the cytomegalovirus-positive donor pool for pediatric recipients.

Update on pediatric heart transplantation. Long-term complications.

Despite evolution to "higher-order" immunosuppressive agents that better control cell-mediated allograft rejection and, therefore, short- and intermediate-term survival, allograft vasculopathy and PTLD remain factors that limit extended graft survival. While improved basic science "bench" techniques have enabled investigation of their pathogenesis at the subcellular and molecular levels, each scientific advance leads the way to the next horizon of complex questions. Only through a more complete understanding of the etiology and pathophysiology of these processes will we be able to design strategies to combat these complications.

Restrictive cardiomyopathies in childhood. Etiologies and natural history.

Restrictive cardiomyopathy is rare in childhood and little is known about the causes and outcome. This lack of information results in extrapolation of adult data to the care and management of children, who might require different treatment from that of adults. This study was undertaken retrospectively to evaluate the causes and natural history of restrictive cardiomyopathy in childhood. Twelve cases of restrictive cardiomyopathy were identified by database review of patient records from 1967 to 1994. The cases were selected on the basis of echocardiographic and cardiac catheterization criteria. Charts were reviewed for the following variables: age, sex, cause, right-and left-sided hemodynamics, pulmonary vascular resistance index, shortening fraction, therapy, and outcome. There were 6 males and 6 females with a mean age of 4.6 years at presentation (median, 3.4 yr; range, 0.9 to 12.3 yr). Etiologies included hypertrophic cardiomyopathy in 3 patients, cardiac hypertrophy with restrictive physiology in 3, idiopathic in 2, familial in 2 (twins), "chronic eosinophilia" in 1, and "post inflammatory" with no definitive causes in 1. At presentation the mean shortening fraction was 33% +/- 2% (mean +/- SEM), average right ventricular pressures were 44/13 +/- 3/1, average left ventricular pressures were 88/25 +/- 4/3, and the mean pulmonary vascular resistance index was 3.4 +/- 1.3 U.m2 (n = 9), but increased to 9.9 +/- 3.1 U.m2 (n = 5, p = 0.04) by 1 to 4 years after diagnosis. Four of the 12 patients had embolic events (1, recurrent pulmonary emboli; 1, saddle femoral embolus; 2, cerebrovascular accidents) and 9 of 12 died within 6.3 years despite medical therapies, which included diuretics, verapamil, propranolol, digoxin, and captopril. In conclusion, restrictive cardiomyopathy in childhood is commonly idiopathic or associated with cardiac hypertrophy, and the prognosis is poor. Embolic events occurred in 33% of our patients, and 9 of 12 patients died within 6.3 years. Within 1 to 4 years of diagnosis, patients may develop a markedly elevated pulmonary vascular resistance index; therefore, transplantation should be considered early.

Heart transplantation in an 8-month-old girl. 10th anniversary report.

In 1984, Dr. Denton A. Cooley led a surgical team that implanted a cardiac allograft in an 8-month-old girl who had end-stage cardiac disease secondary to endocardial fibroelastosis. At that time, experience with cardiac transplantation in infants was limited, and the long-term effects of the procedure were cause for concern. Ten years later, our patient is a healthy 4th-grade student who enjoys a remarkably normal life. She has grown and developed quite satisfactorily, and her heart has enlarged in proportion to her overall somatic growth. Long-term immunosuppression has produced no adverse effects, and the child's medical problems have differed little from those of her peers. This landmark case has yielded preliminary answers to a number of important questions about cardiac transplantation in infants and has confirmed our original opinion that the procedure is well warranted in selected patients.

Postpericardiotomy syndrome in pediatric heart transplant recipients. Immunologic characteristics.

Clinical features of postpericardiotomy syndrome (PPS) occur in pediatric heart transplant recipients despite immunosuppression, which raises questions about the mechanism of PPS. We studied the clinical and immunologic characteristics of 15 pediatric heart transplant patients, ages 1.1 to 17.8 years (mean, 7.5 years); 7 had clinical evidence of PPS (PPS+), and 8 were without clinical features of PPS (PPS-). Indicators of PPS included fever, irritability, pericardial friction rub, leukocytosis without other cause, and pericardial effusion. The onset of PPS was from 9 to 26 postoperative days (mean, 16 days). Immunosuppressive regimens were comparable up to the day of PPS diagnosis in PPS+ patients, and up to day 16 in PPS- patients (average onset of PPS in PPS+ patients). No differences were found between groups with respect to weight-adjusted dosages of cyclosporin A, azathioprine, or corticosteroids. Mean cyclosporin A levels in PPS+ and PPS- patients were 142 +/- 88 ng/mL (mean +/- standard deviation) and 265 +/- 122 ng/mL (p = 0.045), respectively. Echocardiographic data on 3 PPS+ patients within 1 day of PPS diagnosis revealed pericardial effusions ranging from 5 to 24 mm. No data were available on the remaining 4 PPS+ patients. Minimal pericardial effusions (< 10 mm) were seen in 4 PPS- patients during a comparable time period. One PPS- patient required pericardiocentesis. Endomyocardial biopsy rejection grade did not differ between groups. Means pretransplant soluble interleukin-2 receptor levels did not differ between PPS+ and PPS- patients (758 +/- 410 vs 653 +/- 270 IU/mL); nor did the PPS+ pretransplant levels differ from levels obtained 1 or 2 months postoperatively (700 +/- 437 and 751 +/- 367 IU/mL, respectively). Although pretransplant percentages of the standard T-cell (CD2, CD3, CD4, CD8) and B-cell (DR and CD19) markers differed from post-transplant values, the changes could be explained by the immunosuppressive regimen and did not differ between PPS+ and PPS- patients. In the PPS+ patients, however, there were significant increases in the proportion of activated helper T cells (CD4+/25+) and cytotoxic T cells (Leu-7+/CD8+) following heart transplantation in comparison with pretransplant levels. We speculate that these changes in activation marker in PPS+ patients suggest a possible role for cell-mediated immunity in the pathogenesis of PPS in this group of patients.

Intermediate follow-up of pediatric heart transplant recipients with elevated pulmonary vascular resistance index.

OBJECTIVES: This study examined perioperative and intermediate outcomes in pediatric cardiac transplant recipients who had elevated pulmonary vascular resistance indexes preoperatively. BACKGROUND: Elevated pulmonary vascular resistance was associated with poor outcome in previous studies and constitutes a relative contraindication to transplantation. Few studies have evaluated this poor outcome risk factor in pediatric patients. METHODS: To evaluate outcomes of nonneonatal transplant recipients, records were reviewed and divided into Group I (preoperative pulmonary vascular resistance index > or = 6 units.m2) and Group II (pulmonary vascular resistance index < 6 units.m2). Donor/recipient weight ratios, ischemic times, length of intensive care unit stay, posttransplantation infection rates, arrhythmia, response to pretransplantation vasodilator infusions and pulmonary vascular resistance indexes at the first and most recent posttransplantation biopsies were analyzed. RESULTS: Group I (8 patients) had a mean (+/- SEM) pulmonary vascular resistance index of 11.5 +/- 3.5 units,m2; Group II (29 patients) had a mean pulmonary vascular resistance index of 2.3 +/- 0.4 units,m2 (p < 0.002). Pulmonary vascular resistance index decreased from 12.3 +/- 3.9 to 3.9 +/- 0.9 units.m2 (p < 0.05) in 7 Group I patients undergoing vasodilator infusion during pretransplantation catheterization. Thirty-six orthotopic heart transplantations were performed and one heterotopic transplantation. Donor weights exceeded recipient weights by 13% and 31% for Groups I and II, respectively (p > 0.25). Donor ischemic time was 215 min for Group I and 225 min for Group II (p > 0.75). Intensive care unit stay was 11.5 days in Group I and 15.1 days in Group II (p = 0.20). Infection rate was 38% in both groups (p > 0.80). Arrhythmias occurred in 90% of Group I and 42% in Group II (p < 0.03) patients. Pulmonary resistance index in Group I decreased from 11.5 +/- 3.5 to 3.3 +/- 1.2 units.m2 (p < 0.03) by the first posttransplantation biopsy and have not changed subsequently. During 2.3 years (range 0.3 to 8.5) of follow-up, the mortality rate was 25% and 21% for Groups I and II, respectively (p > 0.80). CONCLUSIONS: Group I patients did not require significantly oversized donors, restricted donor locations or longer intensive care unit stays or have higher infection rates; however, arrhythmias were more frequent. Pulmonary resistance index normalized early after transplantation. Pulmonary vascular reactivity may be more important for survival than absolute resistance index.

Neurologic complications of heart transplantation in children.

Neurologic complications can add significant morbidity to otherwise successful orthotopic heart transplantations in children. Complications have been reported to occur in up to 50% of children undergoing heart transplantation. The purpose of this study was to identify the prevalence and outcome of neurologic complications of heart transplantation in children. We reviewed all children who received orthotopic heart transplantation at Texas Children's Hospital from November 1984 to November 1990. Twenty-two patients (ages, 3 weeks to 17 years; mean, 8.5 years) underwent heart transplantation using cardiopulmonary bypass with moderate hypothermia. For analysis, we compared results during the first 3 years of our experience, 1984 through 1987 (group 1), to 1987 through 1990 (group 2). Survival was 45% (5 of 11 patients) for group 1 and 73% (8 of 11 patients) for group 2. A neurologic complication was defined as a change in the neurologic examination and/or status. Neurologic complications included seizures (6 of 22 patients), strokes (3 of 22 patients), unresponsiveness (3 of 22 patients), and change in mental status (2 of 22 patients). Early (within 2 weeks after operation) neurologic complications occurred in 45% (10 of 22 patients), were persistent (sequelae lasting more than 4 months) in 27% (6 of 22 patients), and resulted in death in 9% (2 of 22 patients). Late (after 2 weeks after operation) neurologic complications occurred in 23% (5 of 22 patients), were persistent in 9% (2 of 22 patients), and have occurred in only two survivors. Neurologic factors were not responsible for the cause of death in group 2. No neurologic complications (early or late) were seen in 1 of 11 patients in group 1 as compared with 7 of 11 patients in group 2 (p < 0.015). Serious neurologic morbidity decreased between the two groups after preoperative cyclosporine was avoided and postoperative hypertension was controlled. All survivors are functioning at age-appropriate levels. Although neurologic complications may be frequent, long-term neurologic disability in survivors is rare.

Nonsurgical cure of brain abscess in a neonate.

A 7-day-old girl was found to have meningitis due to Staphylococcus aureus and a left parietal brain abscess. Six weeks treatment with intravenous methicillin resulted in resolution of her right hemiparesis and brain abscess. This is one of the youngest patients successfully treated by medical therapy alone. The case suggests that in carefully selected, closely monitored infants, medical therapy alone can be successful.

Spontaneous remission of presumed congenital acute nonlymphoblastic leukemia (ANLL) in a karyotypically normal neonate.

A 3-hour-old phenotypically normal girl was transferred to Children's Hospital Medical Center because of skin nodules, hepatosplenomegaly, and marked leukocytosis. The predominant cells in the blood, bone marrow, and dermis were monoblasts consistent with congenital leukemia. Known causes of leukemoid reactions were excluded. The infant received two double-volume exchange transfusions but no chemotherapy. As the white blood cell counts decreased, the monocytic cells became more mature, suggesting that the monoblasts had the ability to differentiate. The proliferative capacity of the marrow appeared to be normal as determined by the ability of marrow cells to form colonies in soft agar. Chromosomal analysis of bone marrow blasts including trypsin--Giemsa banding was normal. Three weeks after birth the patient's CBC and physical examination were normal, and the bone marrow was normal by 4 months of age. The patient has remained in remission for over 3 years.