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Background: Transplant coronary artery disease (TxCAD) contributes to a large percentage of late morbidity and mortality among adult heart transplant recipients. Intracoronary ultrasound (ICUS) is a sensitive tool in the diagnosis of TxCAD in adult patients and has allowed analysis of factors contributing to disease development. Experience with ICUS in pediatrics, however, has been limited. By using ICUS we sought to determine the overall prevalence of TxCAD in pediatrics and to characterize factors associated with its development in this population., Methods: Eighty-six studies were performed in 51 pediatric patients a median of 3.4 years after heart transplantation. Evaluation included angiography and ICUS in 83 and angiography alone in 3 studies. Donor and recipient characteristics were obtained. The ICUS images were analyzed for intimal thickening and compared with coronary angiograms. The presence of any intimal thickening on ICUS was considered TxCAD. An intimal index and point of maximal intimal thickening (MIT) were measured. Vessel disease was graded 0 to 4 based on these results. Four patients had evidence of vasculopathy by angiography, whereas 32 patients (63%) had evidence of intimal proliferation by ICUS. Grade 2 or greater disease was present in 19 (37%) patients. A positive correlation was found when comparing time from transplant with intimal index and MIT (p < 0.001). No other factors were found to predict the development of disease. The overall prevalence of disease was 74% in patients studied at least 5 years after transplant. Intracoronary ultrasound can be performed safely in pediatric patients. Transplant coronary artery disease is common in infants and children after heart transplantation, although its prevalence appears to be less than in adult recipients at similar time intervals. We found no factor other than time from transplant was associated with development of disease.

Background: Rejection associated with heart failure or death occurs after pediatric cardiac transplantation but has had limited analysis., Methods: We analyzed the records of 96 consecutive pediatric cardiac transplant recipients who survived to hospital discharge., Results: Eighteen patients (19%) experienced 23 episodes of heart failure or death associated with rejection. Univariate analysis demonstrated black race (p = 0.041), transplantation after 12 months of age (p = 0.032), later time after transplantation (p = 0.037), rejection episode in the first year after transplantation (p = 0.001), and history of two or more rejection episodes (p < 0.001) were significantly associated with rejection seen with heart failure. A multivariate regression analysis identified two or more rejection episodes to be the only independent risk factor for the development of rejection with heart failure (odds ratio 20; 95% confidence limits, 4-104; p < 0.0001)., Conclusions: This study identified pediatric heart transplant recipients with a history of previous rejection episodes to be at a higher risk for symptomatic or fatal rejection. Further studies are needed to determine if intensification of maintenance immunosuppression, long-term rejection surveillance, or both in patients with multiple rejection episodes could reduce morbidity and mortality from rejection.

Background: Scimitar syndrome has a variable presentation based on the age at which the diagnosis is made. In general, infants presenting in heart failure have a greater number of associated anomalies and their prognosis is much worse., Methods: We reviewed the records of all patients under our care at St. Louis Children's Hospital who presented with symptoms attributable to scimitar syndrome during their infancy. Twelve patients were identified. The average age at presentation was 6 weeks., Results: The most common symptom at presentation was tachypnea. The chest roentgenogram demonstrated dextroposition of the heart and hypoplastic right lung. Only 1 patient had the classic "scimitar sign." Cardiac catheterization demonstrated pulmonary hypertension (pulmonary artery systolic pressure, 73.9+/-21.8 mm Hg). The Qp:Qs was 3.1+/-1.5:1. Two patients with severe associated anomalies were treated medically and both died. Two patients underwent occlusion of the systemic collaterals; one died and the other ultimately underwent complete repair due to persistence of the symptoms of heart failure. Two patients had primary right pneumonectomy and both are alive and well. Seven patients underwent complete repair (one after coil occlusion of the systemic arterial collaterals) and one died; three subsequently developed occlusion of the baffle from the orifice of the anomalous pulmonary vein and required pneumonectomy. Two patients required lung transplantation due to persistent pulmonary hypertension in one and recurrent bilateral pulmonary venous stenosis in the other., Conclusions: Infants presenting with scimitar syndrome generally have symptoms of tachypnea and chest roentgenograms showing dextrocardia and hypoplastic right lung. Although repair of the anomalous venous return and ligation of collaterals is generally recommended, right pneumonectomy (either as primary therapy or if repair failed) had similar early and late results.

Background: Perioperative myocardial injury is a major determinant of postoperative cardiac dysfunction for congenital heart disease, but its assessment during this period is difficult. The objective of this study was to determine the suitability of using postoperative serum concentrations of cardiac troponin I (cTnI) for this purpose., Methods: Cardiac troponin I levels were measured serially in the serum of patients undergoing uncomplicated repairs of atrial septal defect (n = 23), ventricular septal defect (n = 16) or tetralogy of Fallot (n = 16). The concentrations were correlated with intraoperative parameters (cardiopulmonary bypass time, aortic cross-clamp time, and cardiac bypass temperature), and postoperative parameters (magnitude of inotropic support, duration of intubation, and postoperative intensive care and hospital stay)., Results: Postoperative absolute cTnI levels were lesion specific, with a pattern of increase and decrease similar for each lesion. For the total cohort, significant correlations between postoperative cTnI levels at all times (r = 0.43 to 0.83, p < 0.05) until 72 hours were noted for all parameters, except for cardiac bypass temperature. When evaluated as individual procedure groups, no significant relationships were noted in the atrial septal defect group, whereas postoperative cTnI levels were more strongly correlated with all intraoperative and postoperative parameters in the ventricular septal defect group than in the tetralogy of Fallot group., Conclusions: This study suggests that cTnI values immediately after operation reflect the extent of myocardial damage from both incisional injury and intraoperative factors. Cardiac tropinin I levels in the first hours after operation for congenital heart disease are a potentially useful prognostic indicator for difficulty of recovery.

Objectives: Using data from a multi-institutional data base, we sought to determine whether hemodynamic data predict duration of survival in children with primary or secondary pulmonary hypertension., Background: Lung transplantation is a therapeutic option for children with pulmonary hypertension. Appropriate timing of lung transplantation requires reliable methods of predicting duration of survival in potential candidates., Methods: A regional data base was used to obtain cardiac catheterization data on 50 children with mean pulmonary artery pressure (mPAP) > 25 mm Hg and indexed pulmonary resistance (Rp) > 4.5 Wood units. Data on survival were obtained from the participating centers., Results: There were 15 patients without congenital heart disease (group 1) and 35 patients with congenital heart disease (group 2) for analysis. Actuarial survival at 1, 2 and 5 years was 86%, 69% and 69% in group 1 and 88% and 77% in group 2, respectively (p = NS). Hemodynamic variables that predicted survival on univariate analysis were mean right atrial pressure (mRAP) (p < 0.0001), mPAP (p = 0.034), Rp (p < 0.0001) and pulmonary flow (p = 0.003), as well as a variable that we generated-mRAP x Rp (p < 0.0001). On multivariate stepwise logistic regression analysis, mRAP x Rp was independently related to survival. A model using mRAP x Rp allows for the estimation of probability of death at 1 and 2 years after catheterization., Conclusions: Hemodynamic variables can predict survival in children with pulmonary hypertension in the presence or absence of congenital heart defects. This information can be used to determine the optimal timing of listing for lung transplantation.

Objective: To establish normal values and determine the impact of congenital or acquired heart disease on serum cardiac troponin I (cTnI)., Methods: Concentrations of cTnI were measured in two groups of children. Group A represented ambulatory pediatric patients with no apparent cardiac disease (n = 120) and patients in stable condition with known congenital or acquired cardiac abnormalities (n = 96); group B was composed of patients admitted to intensive care units with normal echocardiograms (n = 16), with abnormal echocardiograms (n = 36), and those with blunt chest trauma who were thought to have cardiac contusions (n = 7)., Results: The cTnI concentrations were generally less than 2.0 ng/ml in group A and frequently below the level of detection for the assay (1.5 ng/ml). There was no statistical difference between the two outpatient subgroups (p = 0.66). Nine intensive care patients had cTnI values greater than 2.0 ng/ml. Six of these patients, all with abnormal echocardiograms, had values less than 7.7 ng/ml. All improved and had subsequent normal cTnI concentrations. None of the three remaining patients (two with systemic illness (trauma and sepsis) and one with severe pulmonary hypertension), all with values greater than 8.0 ng/ml, survived. Three of the four patients with high likelihood of cardiac contusion had cTnI concentrations greater than 2.0 ng/ml (including one patient who died)., Conclusions: Cardiac troponin-I values are generally not elevated in children with stable cardiac disease or general pediatric conditions. In the context of severe acute illness, significant elevation of cTnI may be an indicator of poor outcome. Elevation of cTnI may also have diagnostic value in cases when cardiac contusion is suspected.

Although accepted therapy in adults, lung transplantation in children is less well established. Reports from the few existing pediatric centers have involved relatively small patient number. Seventy-nine patients underwent 88 lung transplant procedures at St. Louis Children's Hospital between June 1990 and August 1995. Twenty-one transplants (24%) were done in 19 infants and children under the age of 3 yr. Twelve-, 24-, and 48-mo actuarial survival for the primary transplants was 69%, 67%, and 60%, respectively. Survival improved over the course of the program: 12-mo survival for patients transplanted during the first 18 mo was 42% compared with 78% for those transplanted after December 1991. Survival of children transplanted at younger than 3 yr of age was comparable to older children and adults. However, younger children had a lower incidence of acute rejection; none developed bronchiolitis obliterans. Both graft growth and linear growth occurred. Risk factors for early mortality included presence of aortopulmonary collateral vessels and prior thoracic surgery. Risk factors for survival duration included requiring assisted ventilation at the time of transplant, continuous supplemental oxygen requirement, and presence of aortopulmonary collateral vessels. The major late complication was bronchiolitis obliterans, which occurred in 27% of patients and played a role in 64% of late deaths. Investigation of the lower incidence of acute rejection and bronchiolitis obliterans in younger versus older children may reveal important information about the etiology of this disease. The ultimate long-term success of lung transplantation will depend on identification and treatment of the mechanisms responsible. A multicenter data registry would facilitate further clinical studies of pediatric lung transplantation.

Background: There is little published data regarding somatic growth and changes in allograft size after heart transplantation in infants with hypoplastic left heart syndrome., Methods: We evaluated the somatic growth of 26 infants with hypoplastic left heart syndrome who underwent heart transplantation over a 5-year period and measured changes in left ventricular dimensions in 22 of those infants. Age at transplantation was 27 +/- 17 days (mean +/- standard deviation), and the follow-up period was 43 +/- 14 months. Growth and echocardiographic data were converted to standard deviation (Z) scores for comparison with normal populations., Results: Height and weight were always within normal limits (two standard deviations), with a trend toward smaller size throughout the follow-up period. The somatic growth of infants on low-dose maintenance steroids was not significantly different from that of infants withdrawn from chronic steroid regimens. Initial left ventricular posterior wall and septal dimensions were greater than two standard deviations (+4.3 and +6, respectively), probably the result of routine use of oversized donors, but the dimensions decreased to within the normal range during the first year. They then remained within normal limits during follow-up. With one exception at 2 years after transplantation, left ventricular diastolic dimensions were always within two standard deviations of the mean. Left ventricular dimensions of patients with hypertension, rejection, or acute graft failure were not significantly different from patients without these complications., Conclusions: Neonates with hypoplastic left heart syndrome who undergo heart transplantation can be expected to have somatic growth within normal limits. However, the trend toward growth retardation is worrisome. Left ventricular wall dimensions adjust to smaller recipient size during the first year after transplantation and then remain appropriate for the recipient's size over time.

In the setting of functional single ventricle with pulmonary overcirculation, pulmonary artery banding is frequently used to alleviate symptoms and to prepare for staged repair. At subsequent cavopulmonary anastomosis or Fontan procedure, the pulmonary artery may be ligated at the site of the pulmonary band. This article describes the association of embolic stroke and thrombus in a ligated or divided pulmonary artery stump in three patients with functional single ventricle. These events occurred from 1990 through 1992 among the 1700 inpatient pediatric cardiology admissions at two institutions. The patients, ranging in age from 15 months to 9 years, had cerebral infarctions documented by computed axial tomography scan or magnetic resonance imaging associated with the echocardiographic finding of thrombus in the proximal pulmonary artery stump after the embolic strokes. The strokes occurred 5 days to 5 years after surgery. Two patients had a second infarction within 2 to 5 weeks of the initial stroke. It is concluded that the presence of the ligated pulmonary artery stump may place patients at risk for embolic stroke. Surgical approaches to reduce the risk of thrombus formation should be considered prospectively in this patient group.

Background: Experience with lung transplantation in infants and young children is limited. Small size, vulnerability to infection, and limited modalities for rehabilitation and surveillance of the transplanted lung make this group particularly challenging., Methods: We reviewed the course of all children up to the age of 25 months who underwent lung transplantation at two centers between July 1990 and February 1995., Results: Lung transplantation was performed in 17 patients under the age of 25 months, with concurrent cardiac repair in 14. Prior thoracic surgery had been performed in 12; six patients had mechanical ventilation, and three were supported with extracorporeal membrane oxygenation while waiting for lungs. The mean waiting time was 37 days (range 1 to 197 days). Hospital survival was 12 of 17 (71%); there was one late death. Early deaths were due to hemorrhage (two patients), cytomegalovirus and lymphoproliferative disease (one patients), and viral pneumonitis (two patients). The one late death was due to overwhelming gastroenteritis of unknown origin. One additional patient had graft failure caused by viral pneumonitis and underwent successful retransplantation. Bronchial stenosis occurred at 3 of 33 anastomoses. At a mean follow-up of 22 months, surviving patients were well, without supplemental oxygen, and, although small in stature, had normal linear growth., Conclusions: Lung transplantation is a reasonable therapy for very young patients with limited life expectancy and no other therapeutic alternative, with outcomes comparable with those achieved in older patients. Early recognition of lung transplant candidates and advances in the prevention, diagnosis, and treatment of viral illness may improve survival in these patients.

Objective: To characterize the evaluation and clinical course of children with nonpenetrating injury to the heart., Methods: We reviewed the medical records for children admitted to St. Louis Children's Hospital between the years 1987 to 1992 with traumatic cardiac injury. Patients with penetrating trauma were excluded; eight children, ages 4 to 13 years, were the study subjects. Chest x-ray studies, electrocardiograms, and serum creatine kinase values were obtained on admission. Two-dimensional echocardiography was performed when indicated by unexplained hemodynamic instability or abnormal radiographic findings., Results: All children with nonpenetrating cardiac trauma were involved in a motor vehicle accident. The principal cardiac diagnoses were ventricular septal defect (1), mitral regurgitation (1), pericardial effusion (2), contusion (3), and arrhythmia (1). Multisystem injury was present in each case, but cardiac injury was not suspected at the time of admission in seven of the eight patients. The hemodynamic status of four children was compromised 12 to 48 hours after admission; echocardiography was diagnostic in each instance, but the electrocardiogram and creatine kinase values were nonspecific. Two patients eventually required cardiac surgery., Conclusions: Recognition of blunt cardiac trauma in children may be confounded by associated multisystem injury and the delayed onset of clinical manifestations. Echocardiography is a sensitive diagnostic tool for hemodynamically significant disease, and should be performed promptly when patients have unexplained hypotension or diminished peripheral perfusion.

Background: Echocardiography has been used as a primary means to detect cellular rejection in infant heart transplant recipients. There is, however, limited information correlating echocardiography and biopsy-proven rejection in this age group., Methods: Between September 1989 and July 1994, 32 consecutive heart transplantations were done in infants younger than 20 months old, who were followed up for 2 to 58 months (mean 28 months) with concurrent endomyocardial biopsy and M-mode echocardiography with digitization. M-mode data from all 16 episodes of rejection (International Society for Heart and Lung Transplantation grade 3A or greater) that occurred in 12 grafts were compared with data from the same grafts with histologic resolution of rejection 2 weeks after treatment and with data from biopsy-proven nonrejecting control grafts matched for sex, time after transplantation, donor weight, and donor age., Results: Left ventricular mass index increased in rejection (86 +/- 9 gm/m2) versus resolution (64 +/- 6 gm/m2) and versus that in nonrejecting control grafts (59 +/- 8 gm/m2). Left ventricular shortening fraction increased in rejection (40% +/- 2%) versus resolution (38% +/- 10%). Septal thickening fraction decreased in rejection (33% +/- 9%) versus nonrejection (68% +/- 16%). These changes became significant only in grafts transplanted more than 1 month before study. Substantial overlap of measurements prevented identification of threshold values. Intraobserver and interobserver variabilities for standard M-mode data were 7% to 8% and 12% to 22%, respectively, whereas those for digitized parameters were markedly elevated at 37% to 71% and 51% to 81%, respectively., Conclusions: We found (1) left ventricular mass index increases in cellular rejection but may be unreliable less than 1 month after transplantation and (2) significant interobserver and intraobserver variability may limit the applicability of digitized echo parameters to the detection of rejection in infant heart transplant recipients.

Background: Endomyocardial biopsy remains the primary means of rejection surveillance after orthotopic heart transplantation in adults. Perpetual surveillance endomyocardial biopsy has been questioned, however, because of low yield beyond the early posttransplantation period. This issue has not been adequately studied in the pediatric population. The objectives of this study were to define the rate of rejection in infants undergoing orthotopic heart transplantation, correlate rejection with signs and symptoms, and evaluate the utility of surveillance endomyocardial biopsy., Methods: Records of all patients 24 months of age or younger undergoing orthotopic heart transplantation were reviewed; 38 patients underwent 42 transplantation; 256 endomyocardial biopsies were performed for surveillance, cardiac symptoms, noncardiac symptoms, or lowered immunosuppression., Results: There were 22 rejection episodes International Society for Heart and Lung transplantation grade 1B or higher, half of which occurred in neonates 30 days of age or younger. Linearized rejection rates and actuarial freedom from rejection were not different between neonates and older infants. Linearized rejection rates reached a plateau 3 months after orthotopic heart transplantation of 0.07 episodes/100 patient days. No positive surveillance endomyocardial biopsies were obtained beyond 6 months after orthotopic heart transplantation. The probability of a positive biopsy (International Society for Heart and Lung Transplantation grade 1B or higher) was 20% or more for any other indication (odds ratios for rejection were 12.9 for cardiac symptoms, 3.3 for noncardiac symptoms, and 10.8 for lowered immunosuppression as determined by logistic regression more than 6 months after orthotopic heart transplantation)., Conclusions: Rejection rates are not different between neonatal and older infants, and endomyocardial biopsies done solely for surveillance beyond 6 months after orthotopic heart transplantation rarely yield positive results.

Single or bilateral lung transplantation was performed in 20 patients with pulmonary hypertension or an inadequate pulmonary vascular bed; all but 1 had congenital heart disease. The average age was 6.3 years (range, 3 months to 23.9 years). All were in New York Heart Association class IV, and 6 were hospitalized and receiving intensive support before transplantation. Hospital survival was 70% (14/20), with three additional deaths at 7, 11, and 27 months. A prior thoracic operation contributed to three of six hospital deaths from hemorrhage. All late deaths were due directly or indirectly to obliterative bronchiolitis. At a mean follow-up of 19 months (range, 2 to 48 months), 10 of 11 survivors are in New York Heart Association class I. Survival after hospital discharge and incidence of obliterative bronchiolitis are similar in a contemporary group of 41 patients of comparable age who underwent lung transplantation for pulmonary disease (p = not significant). Single or bilateral lung transplantation is an acceptable therapy for children with pulmonary hypertension, congenital heart disease, or both. Further investigation in the areas of pretransplantation survival, operative risk factors, and long-term outcome of single-lung recipients and recipients with hemodynamically insignificant intracardiac lesions are needed to develop optimal decision-making strategies for these patients.

We retrospectively analyzed the impact of recipient, donor, and operative factors on the operative mortality and morbidity of 36 consecutive infant heart transplantations. Operative survival was excellent at 94%. Among 34 survivors, operative morbidity in 12 patients included acute severe allograft failure with or without prolonged ventilatory support. The cohort was characterized by age less than 4 months (32 of 36), a diagnosis of hypoplastic left heart syndrome (29 of 36), and the use of circulatory arrest (27 of 36); these variables were colinear and could not be used to predict operative mortality or morbidity. None of the remaining recipient, donor, or operative characteristics predicted survival or acute severe allograft failure. A donor-to-recipient weight ratio greater than 2 and a circulatory arrest time greater than 39 minutes predicted the need for prolonged ventilatory support. Despite the need for aggressive or prolonged support after 12 of 36 transplantations, operative survival was high at 94% (34 of 36 procedures, 32 of 34 patients). The use of less restrictive donor criteria combined with aggressive management of acute allograft failure can result in excellent operative survival after infant heart transplantation.

Left ventricular (LV) mass and function in 11 patients (group I) with coarctation of the aorta repaired at a mean age of 35 days were compared with that of 14 patients (group II) who underwent repair at a mean age of 8 years. Each group was compared to age- and sex-matched normal control subjects. All patients were normotensive and had resting arm-leg peak systolic blood pressure gradients < 20 mm Hg. Quantitative M-mode echocardiography was used to determine LV mass index and systolic performance. Magnetic resonance imaging was performed to assess residual narrowing of the descending aorta. LV mass index was increased in both groups when compared with control subjects (group I p = 0.01; group II p = 0.007). Whereas systolic performance in group I was similar to its control group, group II patients had enhanced LV systolic performance as measured by shortening fraction (p = 0.007). Multiple regression analysis of combined group I and II patients demonstrated a significant positive correlation of residual aortic narrowing with LV mass index (p = 0.01). Thus, LV mass remains increased in normotensive patients without major blood pressure gradients after repair of coarctation of the aorta in infancy or childhood. Small degrees of residual aortic narrowing were associated with increased postoperative LV mass regardless of the age at repair.

We prospectively evaluated the feasibility of withdrawing steroids 6 to 12 months after heart transplantation in 26 consecutive infants and children (median age at transplantation 6 weeks; range 5 days to 10.1 years) initially treated with triple immunosuppression (cyclosporine, azathioprine, and corticosteroids). Ongoing surveillance for cellular rejection was performed by endomyocardial biopsy in all patients and was performed electively in all subjects within 2 weeks after administration of steroids was discontinued. Significant rejection was defined as grade 2. Twenty-three of 26 patients were 6-month survivors and steroids were withdrawn in 21, with the other two survivors followed up elsewhere with triple immunosuppression. Seventeen (81%) of 21 patients were ultimately treated without maintenance steroids for a mean duration of 17 months (range 1 to 34 months), including 6 of 17 patients who had at least one episode of rejection within the first 6 months of transplantation. Five (24%) of 21 patients had rejection 2 weeks (n = 3) and 6 months (n = 2) after steroids were withdrawn, with one patient successfully withdrawn from steroids after a second attempt. In this latter group one patient underwent retransplantation because of severe coronary arteriopathy by angiography 10 months after transplantation and another died suddenly 18 months after transplantation despite resumption of steroids.(ABSTRACT TRUNCATED AT 250 WORDS)

Background: Infant cardiac transplantation for hypoplastic left heart syndrome (HLHS) can be performed with a high success rate, but it remains unclear whether variations in anatomy or degree of illness before transplantation can affect ultimate survival., Methods and Results: We analyzed the initial echocardiograms and pretransplant courses of 21 infants whose families chose transplantation as a primary therapy option for factors influencing survival. Sixteen of 21 were transplanted (mean wait, 18 days; range, 3 to 97 days) with 15 current (6- to 36-month) survivors, leading to a survival rate from presentation of 71% (70% confidence limit [CL], 61% to 81%) and an operative survival of 94% (70% CL, 81% to 99%). Seven of 20 listed for transplant (35%) had a severely restrictive interatrial communication, defined as a color flow jet width of 3 mm or less across the interatrial septum. Three of these 7 infants died at 4 (2) and 7 (1) weeks from congestive heart failure and progressive hypoxemia before transplantation. One died 2 months after transplant with an autopsy demonstrating pulmonary venous hypertensive disease, leading to a significantly higher relative risk for death (relative risk = 7.4, P = .01) for those infants with a severely restrictive interatrial communication versus those infants without severe restriction. The size and function of the right ventricle, left atrium, aorta, and tricuspid valve, as well as the magnitude of support on presentation, were not related to ultimate survival., Conclusions: A severely restrictive interatrial communication is a frequent component of HLHS. When primary cardiac transplantation is the chosen therapy for HLHS, it is a significant negative risk factor for death primarily before transplantation.

Endomyocardial biopsy has had limited utilization for the diagnosis of myocardial disease in the pediatric population. Through the use of echocardiography for guidance, we attempted 155 consecutive biopsies in 33 patients. A successful biopsy was performed 151 times, including 48 (31%) in infants less than 6 months of age. Biopsies were performed with a right internal jugular approach using 3F, 5F, and 7F bioptomes. A combination of apical four-chamber and parasternal short-axis views could visualize the passage of the bioptome into the ventricle and the action of the jaws. There was no case of ventricular perforation. After biopsy one transplant recipient was left with an increase in the amount of preexisting tricuspid regurgitation by color flow mapping echocardiography. These results demonstrate that echocardiographically guided endomyocardial biopsies may be safely performed over a wide range of patient sizes. The increased portability, lack of radiation exposure, and the simultaneous visualization of the bioptome and chamber wall combined with these results indicate that echocardiographically guided endomyocardial biopsies should be considered the technique of choice for the pediatric population.

Pediatric heart transplant recipients were previously reported to have higher early mortality and morbidity than do adult patients treated with triple immunosuppression therapy (steroids, azathioprine and cyclosporine). Nineteen patients (11 infants and 8 older children) underwent orthotopic transplantation using triple immunosuppression therapy. Surveillance for cellular rejection and coronary arteriopathy was performed with endomyocardial biopsy and selective coronary angiography in all patients, with continuous monitoring for hypertension and serious infection. Seventeen of 19 patients (89%; 10 infants and 7 older children) are current survivors, with a median follow-up of 29 months (range 17 to 94). There were 5 and 7 episodes of rejection in the first 12 months after transplantation in the infant and older groups, respectively, for actuarial freedom-from-rejection rates of 65% at 3 months and 54% at 12 months. Severe coronary arteriopathy was detected in 1 infant 11 months after transplantation. In the first 12 months after transplantation, there were 3 hospitalizations for infection, and 2 patients needed treatment for hypertension in the infant group, compared with 1 hospitalization for infection, and 4 patients on antihypertensives in the older group. An increased prevalence of noninfectious complications in the infant group led to significantly longer postoperative stays than in the older group (mean 27.3 vs 19.4 days; p < 0.05). The results indicate that cardiac transplantation using triple immunosuppression therapy in infants, children and adolescents is associated with a high survival rate, and low rates of rejection and serious infection.

The presence of a left superior vena cava in infants with hypoplastic left heart syndrome complicates the technical performance of orthotopic cardiac transplantation. In this report we describe a modification of the recipient cardiectomy to maintain patency of the left superior vena cava, leaving the recipient coronary sinus as a conduit for it into the right atrium and avoiding complex venous reconstructions.

Surgical repair of coarctation of the aorta in infancy has recently been challenged by some investigators who suggest that balloon angioplasty results in a lower mortality rate and similar risk of restenosis. Over a 44-month period, 37 consecutive infants with a mean age of 33 days (median, 15 days; range, 1 to 200 days) and mean and median weight of 3.7 kg (range, 2.4 to 5.4 kg) underwent surgical repair of coarctation of the aorta with either an end-to-end anastomosis (24 patients) or subclavian flap angioplasty (13 patients). There were no operative deaths (95% confidence interval, 0% to 10%). Four patients died late (> 30 days) after surgery (11%). Four patients (11%) (95% confidence interval, 3% to 25%) had residual gradients greater than 20 mm Hg. A review of the recent literature on treatment of native coarctation in infants with surgical repair (18 reports, 1189 patients) and balloon angioplasty (8 reports, 57 patients) reveals a similar early mortality rate but a much higher rate of recoarctation in infants who were treated with balloon dilation (57%) as compared with those who underwent surgical repair (14%). Because of the incidence of restenosis, balloon dilation as compared with surgical repair does not yet offer an improved outcome for native coarctation of the aorta in infancy.

Infants with single ventricle and transposition of the great arteries with or without aortic arch obstruction have a poor prognosis due in large part to the development of systemic outflow obstruction, a frequent consequence of pulmonary artery banding. Thus, the initial palliation and long-term treatment options are critical in terms of surgical choices and timing. We report our experience with 9 patients managed by neonatal pulmonary artery banding and early debanding, a Damus-Kaye-Stansel procedure, and either a modified Glenn shunt or a modified Fontan procedure. Some evidence of subaortic stenosis developed in every patient as manifested by a resting gradient across the systemic outflow tract (21.4 +/- 4.2 mm Hg), a small ventricular septal defect relative to the body surface area (1.57 +/- 0.39 cm2/m2), and a small ventricular septal defect relative to the aortic root cross-sectional area (0.70 +/- 0.04 cm2/m2). There were 1 early death and 1 late death after the Damus-Kaye-Stansel procedure. With the exception of 1 patient, the in-hospital course of the survivors was relatively uncomplicated. Two patients with levotransposition of the great arteries have required pacemakers. None of the survivors have residual systemic outflow obstruction. There is trivial or mild pulmonic insufficiency in 5 patients, which is not progressing. One patient had mild to moderate pulmonic insufficiency but died late presumably of an arrhythmia. We conclude that neonatal pulmonary artery banding coupled with planned early debanding, a Damus-Kaye-Stansel procedure, and cavopulmonary anastomosis is a relatively low-risk course for patients with this complex physiology.

Five children underwent lung transplantation for end-stage pulmonary hypertension and respiratory insufficiency associated with congenital heart disease. One (17 mo) had pulmonary hypertension with a patent ductus arteriosus and required two periods of preoperative extracorporeal membrane oxygenation before successful bilateral sequential lung transplantation. One (21 mo) required bilateral lung transplantation for pulmonary hypertension and bronchopulmonary dysplasia associated with iatrogenic injury to the left pulmonary artery. This child also had patent ductus arteriosus ligation and preoperative catheter closure of an atrial septal defect. Extracorporeal membrane oxygenation was required for early postoperative pulmonary support. One child underwent right single-lung transplantation and closure of an atrial septal defect for pulmonary hypertension. Two patients had single-lung transplantation for Eisenmenger's syndrome: 1 with muscular inlet ventricular septal defect closure, atrial septal defect closure, and right single-lung transplantation; 1 with ventricular septal defect closure, patent ductus arteriosus ligation, right ventricular outflow tract patch repair, and single-lung transplantation. All patients survived operation, with one late death (lymphoproliferative disease). The 4 survivors are all ambulatory without oxygen and have evidence of normal pulmonary artery pressure 9 to 12 months after transplantation.

Fifteen children and adolescents who had repair of coarctation of the aorta before age 15, who were not hypertensive at rest, and who had resting arm-leg blood pressure gradients of less than 20 mm Hg underwent noninvasive evaluation of left ventricular structure and function, aortic stiffness, and residual coarctation as well as bicycle exercise testing. These results were compared with those in 15 age- and sex-matched control subjects. The mean resting age-related systolic blood pressure percentiles (63% versus 46%), transverse aortic stiffness measured by the elastic modulus (Ep) (42.1 versus 23.2 kPa), stiffness index beta (beta) (3.66 versus 2.17), echocardiographic left ventricular fractional shortening (0.42 versus 0.36), left ventricular mass index (99.3 versus 81.0 gm/m2), maximum exercise right arm systolic blood pressure (173 versus 156 mm Hg), and exercise arm-leg blood pressure gradient (35 versus 6 mm Hg) were significantly increased in the coarctectomy patients compared with controls. Univariate correlations in the coarctectomy group showed significant relationships of residual aortic narrowing with left ventricular mass index (r = 0.68, p less than 0.01) and resting systolic blood pressure percentile for age (r = 0.55, p less than 0.05). Residual aortic narrowing did not significantly correlate with aortic stiffness, resting blood pressure gradient, or exercise blood pressure gradient. Neither left ventricular mass index nor resting systolic blood pressure percentile significantly correlated with age of repair or years after repair. These results demonstrate persistent abnormalities in aortic stiffness and left ventricular mass and function after successful repair of coarctation of the aorta in childhood and adolescence.(ABSTRACT TRUNCATED AT 250 WORDS)

From July 1988 to March 1991, extracorporeal membrane oxygenation (ECMO) was used in 8 infants (newborn to 16 months old) with unoperated cyanotic congenital heart disease and cardiopulmonary collapse, associated with hypercyanotic spells (4 infants), pulmonary hypertensive crises (3) and sepsis (1). Indications for ECMO support were arterial saturations less than or equal to 60% accompanied by hypotension and metabolic acidosis unresponsive to mechanical ventilation with 100% oxygen, paralysis and sedation, and pharmacologic support with inotropes or vasodilators, or both. Venoarterial bypass by carotid/jugular cannulation with flow rates of 100 to 840 ml/kg/min (mean 460) stabilized all patients. Duration of ECMO support ranged from 15 to 840 hours and was associated with transient seizures (1 patient) and renal failure (1). Seven patients underwent palliative (3 patients) or corrective (4) surgical procedures while on ECMO or within 48 hours of decannulation, including 1 patient bridged to double-lung transplantation with a long (840 hours) duration of ECMO. There was 1 operative and 2 late (greater than 1 month after decannulation) deaths, for an overall survival rate of 62%. These 5 survivors all have normal growth and development, and patent neck vessels at the site of cannulation. These early results indicate that ECMO can be effective mechanical support in cardiovascular crises untreatable with maximal conventional medical therapy and can be used as a bridge to successful surgical palliation or repair.

Herein, a policy of primary surgical closure of large ventricular septal defects in infants is reviewed. Forty-eight infants met criteria for inclusion in the study, and were divided into two groups based on weight: group 1 infants weighted 4 kg or less (n = 23), and group 2 infants weighed more than 4 kg (n = 25). Both groups had similar variation in ventricular septal defect location (paramembranous versus muscular) and number (single versus multiple), as well as incidence of major associated extracardiac diseases. No early deaths occurred in group 1, compared with 1 infant (4%) in group 2. Major complications occurred similarly in both groups (9% versus 12%). There were two late deaths in group 1 (9%) and none in group 2. No surviving patients have required a second ventricular septal defect operation, and the majority no longer receive anticongestive therapies. These results indicate that primary surgical closure of large ventricular septal defects, even multiple muscular defects, can be performed in very small infants with no difference in mortality or serious complication rates compared with larger infants. Protracted medical efforts to achieve larger size before primary repair and palliative pulmonary artery banding are not necessary.

Echocardiographically guided endomyocardial biopsy via percutaneous right internal jugular vein puncture has been performed 98 times in six patients 5-16 years of age at our institutions. The use of this approach was extended for rejection surveillance in seven infants transplanted at 2 weeks to 15 months of age (median, 2 months; mode, 2 weeks). A total of 35 consecutive biopsies were performed under heavy sedation in these infants (lowest weight, 3.0 kg) with the use of a 5F semirigid bioptome through a 5.0-cm 5F sheath. There was no case of entrance failure. A median of four biopsies was performed on each child (range, one to 14). Four to seven tissue pieces per biopsy were obtained using an apical four-chamber view for bioptome guidance. Ten instances of clinically suspected rejection were not confirmed by biopsy, and two cases of unsuspected rejection were found. The only complication was one instance of new mild tricuspid regurgitation in this group compared with one instance of increased tricuspid regurgitation after biopsy in the older child group. These preliminary results suggest that echocardiographically guided endomyocardial biopsy from the right internal jugular approach is a reliable and safe means for rejection surveillance in the infant and young child.

Although triple-drug immunosuppression (cyclosporine, azathioprine, and prednisone) has reduced the incidence of acute rejection after pediatric cardiac transplantation, its effect on the development of coronary artery disease, which may be the major determinant of long-term survival in these patients, is not well defined. We reviewed 42 coronary angiograms obtained annually in 17 cardiac transplant recipients, aged 6 months to 18 years (mean, 12.4 years) at the time of transplantation, who had been maintained on triple-drug immunosuppression and had survived at least 1 year after transplantation. Each angiogram was reviewed for luminal irregularities or discrete stenoses, for the loss of third-order branching, and for the presence of myocardial bridging or calcification of vessels. Patient files were reviewed for donor and recipient age, sex, and ABO blood group, for postoperative episodes of rejection or cytomegalovirus infection, for hypertension, and for cholesterol and triglyceride values. No recipient in our series has died or undergone retransplantation because of coronary artery disease. Six of 17 (35%) patients have developed angiographically identifiable coronary artery abnormalities: four by the first year and two additional recipients by the second and third years, respectively, after transplantation. Development of coronary artery abnormalities approached a significant correlation when related to posttransplantation cytomegalovirus infection (p = 0.11) and older recipient age (p = 0.056) but not to any other factors studied, including episodes of rejection (p = 1.0). Angiographically identifiable coronary artery abnormalities can occur in pediatric recipients within the first year after cardiac transplantation in spite of a low incidence of acute rejection. Although the abnormalities may be mild initially, they can progress and require intervention.(ABSTRACT TRUNCATED AT 250 WORDS)

This study was undertaken to compare electrocardiographically gated magnetic resonance imaging (MRI) to established imaging modalities in the detection of complex intra- and extracardiac morphologic defects. Twenty-three patients with congenital cardiac abnormalities were imaged by four methods: cardiac catheterization, echocardiography, two-dimensional (2D) transaxial MRI, and three-dimensional (3D) MRI surface reconstruction. Observers with experience in congenital cardiac disease diagnosis (two for echo, one for catheterization, two for 2D MR, and three for 3D MR) evaluated the images in a blinded fashion, and the results were analyzed with receiver operating characteristic (ROC) analysis. Overall, cardiac catheterization had the best diagnostic performance. The diagnostic value of routine 2D cardiac MR images and 3D MR reconstruction images were similar to that of echocardiography. All of the modalities performed poorly in the diagnosis of extracardiac defects and atrial septal defects.

Right-sided extracardiac conduits are frequently complicated by obstruction over time. We compared the utility of two-dimensional and Doppler echocardiography and magnetic resonance imaging in the diagnosis of postoperative right-sided obstruction with cardiac catheterization and angiography in 10 patients with xenograft or homograft conduits. Correlation (r = 0.95) between continuous-wave Doppler estimates and catheter pullback pressure gradients across the conduits was excellent. Echocardiography could only visualize five of 10 conduits in their entirety. Magnetic resonance imaging visualized all conduits and showed statistically significant (kappa = 0.58) agreement with angiography in the localization and estimation of severity of a variety of right-sided obstructions in these patients. However, flow voids created by the metallic ring around xenograft valves led to a false negative diagnosis of valvular stenosis in four patients when magnetic resonance imaging was used alone. Doppler studies correctly indicated obstruction in these patients. The combination of magnetic resonance imaging studies and continuous-wave Doppler echocardiography can be useful to noninvasively evaluate right-sided obstruction in postoperative patients with right-sided extracardiac conduits.

A 15-month-old boy developed monoblastic leukemia. Two-dimensional echocardiogram revealed two echolucent masses on the epicardial border of the right ventricle which were suspected to be leukemic infiltrates. This was confirmed at autopsy. The echocardiographic findings are discussed.

Cardiac transplantation has only recently become an accepted therapeutic modality for children and adolescents with end-stage cardiomyopathy. Long-term survival, the incidence of rejection, and the incidence of infection are still being defined. From 1985 to 1989, 21 children aged 6 months to 19 years (average age, 11.2 years) underwent cardiac transplantation at our institutions. Eighteen survived the operative period and have been followed for 5 to 49 months (average follow-up, 24 months). All operative survivors have received triple-drug immunosuppression consisting of cyclosporine, azathioprine, and prednisone. During follow-up, 7 patients have been treated on 12 occasions for rejection as documented by endomyocardial biopsy. Eight (67%) of the 12 episodes of rejection occurred in the presence of subtherapeutic cyclosporine levels. Two of the 7 patients treated for rejection have subsequently died of ongoing cardiac rejection and arrhythmia. There have been no perioperative or late deaths from infection. Bacterial sepsis was identified and treated twice during follow-up, viral infections on five occasions, and fungal infection once. Actuarial 1-year survival and 3-year survival of the 18 operative survivors are 94% and 78%, respectively. In the first 7 months after cardiac transplantation, 73% of patients were free from rejection and 83% were free from serious bloodborne infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Before and after surgical therapy, the anatomy of the pulmonary arteries in cyanotic congenital heart disease is often distorted. Pulmonary arterial anatomy was evaluated by magnetic resonance imaging (MRI) and angiography in 20 patients, ages 3 months to 20 years, with cyanotic heart disease associated with decreased pulmonary blood flow. Excellent correlation between MRI and angiographic estimates of pulmonary artery diameter was obtained (main pulmonary artery, r = 0.96; right pulmonary artery, r = 0.93; left pulmonary artery, r = 0.96). A similar excellent correlation (kappa = 0.83) was found in the assessment of the presence and severity of proximal pulmonary arterial stenoses. However, stenoses in the peripheral pulmonary arteries visualized with angiography were missed with MRI. MRI and angiography showed complete agreement in determining the patency of 11 surgical shunts. MRI did not demonstrate all of the systemic collateral vessels present with angiography, and the distal connections of collaterals were not detected with MRI. MRI is comparable to angiography in the evaluation of central pulmonary arterial anatomy over a wide range of ages. These findings suggest an important role for noninvasive MRI in the serial evaluation of pulmonary artery morphology in patients with cyanotic congenital heart disease before and after surgical repair.

Surgical treatment of patients with tetralogy of Fallot requires accurate definition of all anatomic structures, particularly the central pulmonary arteries. Magnetic resonance (MR) images of 22 patients with tetralogy of Fallot were studied to assess their usefulness in providing information regarding the spectrum of anatomic abnormalities in this condition. MR findings were compared with information obtained at catheterization (in 16 patients) and at surgery (in nine patients), both of which were performed within 3 months of MR imaging. Ventricular chamber enlargement and wall hypertrophy were clearly delineated in most of the 17 patients who were examined before definitive surgical repair, and ventricular septal defects were visualized in all 17. Palliative systemic-to-pulmonary shunts were visualized in 11 patients and could be evaluated for patency. Most important, the morphology and size of the right ventricular outflow tract and central pulmonary arteries could be accurately assessed. Pulmonary artery measurements obtained from MR images demonstrated excellent correlation with angiographic measurements. In six patients examined after complete surgical repair, MR images accurately reflected changes in pulmonary artery outflow tract morphology and complications, such as residual pulmonary artery stenosis and thrombosis. The findings suggest that MR imaging can complement or obviate catheterization in the evaluation of tetralogy of Fallot with regard to suitability for definitive surgical repair.

The normal number of glomeruli per kidney in the rat rises from about 10-4 at birth to approximately 35 times 10-3 at 50 days of age. When one kidney is removed at birth the remaining one produces an average of 63% more nephrons than normal by 70 days. Unilateral nephrectomy of successively older rats results in progressively less augmentation of the nephron complement in the remaining kidney up to 50 days, beyond which age the kidney loses its ability to produce new nephrons.

Three-dimensional surface images of the human heart may be produced from magnetic resonance imaging. These examinations are used in the evaluation of congenital heart disease for preoperative planning and postoperative evaluation. Computer graphics software has been adapted to produce three-dimensional images of the beating heart from contiguous two-dimensional serial EKG-triggered magnetic resonance image data sets. The natural boundary between flowing blood and cardiac tissue serves to outline cardiac structures. The techniques for producing these images and pitfalls in the operation of the system as well as examples of their application to the study of patients with congenital heart disease are outlined in this article.

The management and follow-up of 12 patients with major aortic thrombus formation occurring in the neonatal period between 1982 and 1987 are reported. Umbilical arterial catheters were inserted in 8 of the 12 patients before thrombus formation. Two patients had congenital thrombi. Hypertension, oliguria, hematuria, and elevated blood creatinine concentration were found at the time of diagnosis of the thrombus; nine of the patients had a patent ductus arteriosus. Supportive care was instituted in seven patients who were hemodynamically stable. Five of the patients had congestive heart failure, shock, or both, and were treated with surgical thrombectomy. Thrombolytic therapy was not used in either group. The five surgically treated patients and six of seven medically treated patients survived. Ultrasound examination suggested resolution of the thrombus in all survivors in 6 to 30 days. Sequelae from thrombus formation were present in all patients at the time of discharge and included hypertension in 9 of the 11 survivors and decreased renal function in six of them. Follow-up at 1 to 3 years revealed normal blood pressure, good growth, and good renal function in 10 of the survivors.

Despite improving survival rates after repair of atrioventricular septal defect, many patients require reoperation because of postoperative heart failure. We used intraoperative color flow mapping echocardiography to assess the results of surgical repair of atrioventricular septal defect in 19 consecutive patients and compared those findings with results three to five days and 3 to 11 months after repair. There was close correlation between intraoperative and postoperative color flow mapping echocardiography in estimating the presence and severity of left atrioventricular valve regurgitation. All patients survived surgical repair, but in 4 (21%), postoperative congestive heart failure due to left atrioventricular valve regurgitation developed. The need for reoperation was significantly correlated with the severity of left atrioventricular valve regurgitation (r = 0.68) as estimated by intraoperative echocardiography and preoperative aberrancies in the atrioventricular valve (r = 0.68). Age, weight, additional congenital heart disease, preoperative pulmonary vascular resistance, preoperative atrioventricular valve regurgitation, and postoperative mean pulmonary arterial or left atrial pressure were not significantly correlated with the need for reoperation. Intraoperative color flow mapping echocardiography can accurately predict the development of early postoperative heart failure and subsequent reoperation after surgical repair of atrioventricular septal defect.

Three-dimensional surface reconstruction images of the heart and great vessels have been produced from contiguous sequences of EKG-triggered MRI scans in more than 35 patients with congenital heart disease and 5 normal subjects. The scan data was semiautomatically processed to separate the epi- and endocardial surfaces and to define the outlines of the enclosed blood volumes on a slice by slice basis. Surface reconstruction images aid communication with clinicians, establish the size and location of intracardiac defects, and image the pulmonary venous drainage. The method is practical for use in the evaluation of cardiac morphologic abnormalities, especially for planning cardiac surgery.

To define the dependence of cardiac cycle-dependent variation of integrated backscatter on regional myocardial wall motion, 8 children mean age 10.6 +/- 1.3 y with congenital cardiac lesions associated with paradoxical septal motion were studied (study group). Six healthy children mean age 9.0 +/- 0.3 y with no history of cardiac disease served as controls (control group). Subjects in the study group had paradoxical septal motion but normal septal wall thickening detected by conventional two-dimensional and M-mode echocardiography. The control group had normal septal motion evident by conventional echocardiographic criteria. The percentage of systolic septal thickening was 46 +/- 4.5% and 42 +/- 5.9% in the study and control groups (p = NS). Cyclic variation was measured in parasternal long-axis views from several septal sites in each subject. Mean values of the magnitude of cyclic variation from independent septal sites were averaged to yield a regional average value for each subject. The average regional magnitude of cyclic variation was 8.3 +/- 1.0 dB and 5.7 +/- 0.4 dB in the study and control groups (p = NS). The results indicate that the measurement of cyclic variation of integrated backscatter is not distorted by altered regional wall motion, and that it reflects intrinsic contractile function.