The failing Fontan: options for surgical therapy

The Fontan procedure has been a significant contribution to the therapeutic armamentarium of congenital heart surgeons for the treatment of single ventricle anomalies. However, it has its limitations. Patients may have failure of the Fontan circulation acutely postoperatively or late during the long-term follow-up. Early failure is often related to an intraoperative myocardial injury or unsuspected elevated pulmonary vascular resistance; this has a very high mortality. Late failure of the Fontan procedure may present with symptoms typical for heart failure. However, protein-losing enteropathy is another condition related to late failure of the Fontan operation. Late failure may be related to a number of different factors, many of which are amenable to reoperation. Every effort should be made to identify which hemodynamic factors are responsible for late failures. However, cardiac transplantation will likely be necessary for the majority of patients.

Mortality and Morbidity in Pre-sensitized Pediatric Heart Transplant Recipients With a Positive Donor Crossmatch Utilizing Peri-operative Plasmapheresis and Cytolytic Therapy

BACKGROUND

The difficulty in obtaining a prospective negative donor/recipient crossmatch limits the ability to successfully transplant pediatric heart transplant candidates who show evidence of antibodies to multiple human leukocyte antigens (pre-sensitized patients).

METHODS

We utilized a protocol that included peri-operative plasmapheresis, thymoglobulin and cyclophosphamide in 17 pre-sensitized (panel-reactive antibodies [PRA] >10%) pediatric patients to accept donors for these patients without a prospective crossmatch between 1995 and 2005. A retrospective review of survival, rejection and infection was performed, comparing the frequency of rejection and infection in our patients who were transplanted with a complement-dependent cytotoxic (CDC)-positive donor/recipient crossmatch to those patients transplanted with a negative crossmatch.

RESULTS

Thirteen of 17 patients were found to have a CDC-positive crossmatch. Actuarial survival after transplantation was 85% at 1 year and 73% at 3 years. Twelve of 13 (92%) of these patients experienced rejection, and 5 of 13 (38%) had recurrent rejection, generally in the first 2 months after transplantation. Rejection was associated with hemodynamic compromise in 58% of first rejection episodes and 67% of episodes of recurrent rejection. The frequency of rejection in these patients was significantly greater than the frequency in patients with a negative crossmatch in the first 6 months after transplantation, but not afterward. The frequency of infection episodes was not significantly different between the groups.

CONCLUSIONS

Heart transplantation in pre-sensitized pediatric recipients with a CDC-positive donor/recipient crossmatch may result in reasonable short-term survival, but with a high frequency of early rejection, often with hemodynamic compromise.

Lower Incidence of Bronchiolitis Obliterans in Pediatric Liver−Lung Transplant Recipients With Cystic Fibrosis

BACKGROUND

Simultaneous liver-lung transplantation is an infrequent but technically feasible procedure in patients with end-stage lung disease and advanced liver disease. We characterize the outcomes of pediatric patients who underwent this procedure at our institution.

METHODS

We performed a retrospective, case-control study and reviewed the medical records of all patients referred to our transplant program from its inception. Seven patients were listed for simultaneous liver-lung transplant. The five patients who survived to transplant were matched to 13 controls who underwent isolated bilateral sequential lung transplant for underlying diagnosis, age at time of transplant, gender, and era of transplant. Outcome measures included patient and graft survival, occurrence of bronchiolitis obliterans (BO), and episodes of rejection.

RESULTS

Of the five study patients who underwent liver-lung transplant, one died of multiorgan failure 11 days after transplant compared with 9 of 13 controls who died. The median survival for the study patients was 89 months (range, 0-112 months) compared with the controls, who had a median survival of 34 months (range, 0-118 months). The remaining four patients had bronchiolitis obliterans syndrome scores of 0 compared with 5 of 13 control patients (P=0.02). The rate of acute rejection per 100 patient days was 0.012 for the study patients compared with 0.11 for the controls (P=0.025).

CONCLUSIONS

Simultaneous liver-lung transplantation is a technically feasible procedure with excellent long-term outcomes. The surviving study subjects remain free from bronchiolitis obliterans syndrome. These results suggest that the transplanted liver may bestow immunologic privilege to the lung allograft.

Safety and efficacy of prolonged cytomegalovirus prophylaxis with intravenous ganciclovir in pediatric and young adult lung transplant recipients

CMV infection causes morbidity and mortality after transplantation. Despite a wide range of prevention strategies among pediatric lung transplant programs, the optimal duration of prophylactic therapy against CMV infection in pediatric lung transplantation is unknown. To assess the feasibility, safety, and short-term efficacy of extending intravenous ganciclovir administration from six wk duration to 12 wk duration in pediatric lung transplant recipients. An open-label pilot study was performed in primary pediatric lung transplant recipients with donor and/or recipient CMV seropositivity. Intravenous ganciclovir was given for 12 wk post-transplantation. Subjects were tracked for protocol completion. Toxicities monitored included renal dysfunction, myelosuppression, gastrointestinal and neurological complications, as well as infection related to indwelling catheter placement. Serial CMV levels were measured to determine short-term efficacy of the intervention. Nine of nine subjects enrolled completed the pilot study. Subjects' ages ranged from six to 18 yr. Indications for lung transplantation included cystic fibrosis (n = 7), idiopathic pulmonary hypertension (n = 1), and complex congenital heart disease with pulmonary hypertension (n = 1). Seven subjects underwent deceased donor bilateral lung transplantation and two subjects underwent heart-lung transplantation. No subjects had protocol-defined drug toxicity. No episodes of neutropenia, thrombocytopenia, or renal toxicity occurred. Five subjects had catheter-related infections (three after week 12 of ganciclovir). Seven of nine subjects had CMV detected by PCR (four prior to ganciclovir completion) with only one subject having a positive viral culture for CMV viremia (prior to ganciclovir completion). No subjects had UL-97 mutation for ganciclovir resistance detected. The use of prolonged prophylactic administration of ganciclovir for 12 wk duration is a feasible, safe, and effective treatment to prevent CMV viremia based on viral culture in at risk pediatric lung transplant recipients. Further clinical studies are underway to determine optimal CMV prevention strategies.

Pre-transplant Mechanical Ventilation Increases Short-term Morbidity and Mortality in Pediatric Patients With Cystic Fibrosis

BACKGROUND

Patients with cystic fibrosis (CF) who are listed for lung transplantation may require mechanical ventilatory support before transplant. Although CF is a risk factor for poor outcomes in adults, no data currently exist pertaining to pre-transplant ventilatory support in children with CF.

METHODS

In a retrospective cohort study, we reviewed the medical records of 18 consecutive CF patients transplanted at St. Louis Children's Hospital (SLCH) who required mechanical ventilation before lung transplantation. Controls included patients transplanted at SLCH who were not mechanically ventilated before transplant and were matched for underlying diagnosis, gender, age, type of transplant (cadaveric vs living donor) and year of transplant.

RESULTS

Ventilated and non-ventilated patients were similar in their pre-transplant characteristics (weight, height and body mass index) and ischemic and bypass times. However, patients ventilated before transplantation had significantly worse immediate post-transplant outcomes, including early graft dysfunction (p = 0.012), prolonged mechanical ventilation (34.1 vs 5 days, p = 0.009), prolonged stay in the pediatric intensive care unit (35.4 vs 8.1 days, p = 0.01), longer time to hospital discharge (38.4 vs 21.3 days, p = 0.033), and worse 1-year mortality after transplant (221.6 vs 335.2 days, p = 0.021). Among ventilated patients, length of pre-transplant ventilation did not affect post-transplant outcomes (length of ventilation, p = 0.92; length of stay in the pediatric intensive care unit, p = 0.68; time to hospital discharge, p = 0.46; and 1-year mortality rate, p = 0.25).

CONCLUSIONS

This is the first report in pediatric patients with CF demonstrating that mechanical ventilation before lung transplant is a predictor of poor short-term outcomes, including 1-year-survival, after transplant. Length of pre-transplant ventilatory support does not appear to impact outcomes.

Infant Heart Transplantation Ten Years Later—Where Are They Now?

BACKGROUND

Many uncertainties regarding the fate of children undergoing heart transplantation as infants were present when we and others embarked on this program. Although no truly long-term results are available, a significant cohort of children has now reached preteen and early teenage status. We reviewed our group of infants transplanted more than 10 years ago to assess survival and quality of life as they approach their teenage years.

METHODS

We retrospectively reviewed the medical records of all infant (younger than 6 months of age) heart transplant recipients, transplanted between 1988 and 1995, to ascertain survival statistics, incidence of complications, and current health status.

RESULTS

A total of 42 patients were identified. The majority of these underwent transplantation for hypoplastic left heart syndrome. Eleven patients have died, 4 early and 7 late. The actual survival at 10 years is 76%. Twenty-seven of the 31 long-term survivors attend regular school; 4 are in special education classes owing to developmental delay. Five patients take medication for attention-deficit disorder. Malignancies have been discovered in 5, and 1 died secondary to this. Six patients have significant renal insufficiency, 1 of whom has undergone renal transplantation. One patient has undergone retransplantation for coronary artery disease. One patient required reoperation for supravalvar aortic stenosis. Other general medical problems that are being treated include sleep apnea (n = 1), hypertension (n = 5), and recurrent pneumonias (n = 1).

CONCLUSIONS

Although these children require ongoing medical attention, including daily medications and regular follow-up visits, most have a satisfactory quality of life and behave much like normal children.

A new era in the surgical treatment of atrial fibrillation: the impact of ablation technology and lesion set on procedural efficacy

BACKGROUND/OBJECTIVE

While the Cox-Maze procedure remains the gold standard for the surgical treatment of atrial fibrillation (AF), the use of ablation technology has revolutionized the field. To simplify the procedure, our group has replaced most of the incisions with bipolar radiofrequency ablation lines. The purpose of this study was to examine results using bipolar radiofrequency in 130 patients undergoing a full Cox-Maze procedure, a limited Cox-Maze procedure, or pulmonary vein isolation alone.

METHODS

A retrospective review was performed of patients who underwent a Cox-Maze procedure (n = 100), utilizing bipolar radiofrequency ablation, a limited Cox-Maze procedure (n = 7), or pulmonary vein isolation alone (n = 23). Follow-up was available on 129 of 130 patients (99%).

RESULTS

Pulmonary vein isolation was confirmed by intraoperative pacing in all patients. Cross-clamp time in the lone Cox-Maze procedure patients was 44 +/- 21 minutes, and 104 +/- 42 minutes for the Cox-Maze procedure with a concomitant procedure, which was shortened considerably from our traditional cut-and-sew Cox-Maze procedure times (P < 0.05). There were 4 postoperative deaths in the Cox-Maze procedure group and 1 in the pulmonary vein isolation group. The mean follow-up was 13 +/- 10, 23 +/- 15, and 9 +/- 10 months for the Cox-Maze IV, the pulmonary vein isolation, and the limited Cox-Maze procedure groups, respectively. At last follow-up, freedom from AF was 90% (85 of 94), 86% (6 of 7), and 59% (10 of 17) in the in the Cox-Maze procedure group, limited Cox-Maze procedure group, and pulmonary vein isolation alone group, respectively.

CONCLUSIONS

The use of bipolar radiofrequency ablation to replace Cox-Maze incisions was safe and effective at controlling AF. Pulmonary vein isolation alone was much less effective, and should be used cautiously in this population.

Long-term outcomes after infant lung transplantation for surfactant protein B deficiency related to other causes of respiratory failure

OBJECTIVE

To determine if the outcomes of lung transplantation for infants with surfactant protein-B (SP-B) deficiency are unique.

STUDY DESIGN

From a prospective analysis to identify infants with genetic causes of surfactant deficiency, we identified 33 SP-B-deficient infants from 1993 to 2005, and, among those undergoing lung transplantation (n = 13), compared their survival, pulmonary function, and developmental progress with infants who underwent transplantation at <1 year of age for parenchymal lung disease (n = 13) or pulmonary vascular disease (n = 11).

RESULTS

Five-year survival rates ( approximately 50%, P = .3) and causes of death were similar for all three groups once the infants underwent transplantation. However, significant pretransplantation mortality decreased 5-year survival from listing to approximately 30% (P = .17). Pulmonary function, development of bronchiolitis obliterans, and school readiness were similar among the three groups. We detected anti SP-B antibody in serum of 3 of 7 SP-B-deficient infants and none of 7 SP-B-sufficient infants but could not identify any associated adverse outcomes.

CONCLUSIONS

Long-term outcomes after infant lung transplantation for SP-B-deficient infants are similar to those of infants transplanted for other indications. These outcomes are important considerations in deciding to pursue lung transplantation for infants with disorders of alveolar homeostasis.

Outcomes and late complications after pulmonary resections in the pediatric population

Neonates and children undergo lung resections for a variety of indications. These procedures can be performed with low mortality and low morbidity rates in the early postoperative period. There exist important anatomic and physiologic differences between the pediatric and the adult population, which thoracic surgeons need to be aware of. On the one hand, the capacity of the lung to grow during the first few years of life is associated with relative preservation of postoperative pulmonary function in children. On the other hand, the relative flexibility of their tissue structures places pediatric patients at increased risk for developing postpneumonectomy syndrome. Moreover, surgeons need to take the child's growth and development into consideration when planning their operative approach for thoracic procedures.

Pediatric lung transplantation

Lung transplantation in children has been performed since the early 1990s. The indications are cystic fibrosis, pulmonary vascular disease, and a variety of other pulmonary problems leading to death in small children. These other diseases include abnormalities in the metabolism of surfactant producing severe respiratory insufficiency in newborn infants. Many problems accompany these patients before transplantation and many problems are produced both by the transplant itself and immunosuppressant drugs which these children are obliged to take following transplantation. Nonetheless, lung transplantation offers the only real hope of survival in many instances. The long-term results have been somewhat discouraging with a 5-year survival of approximately 50%. The major causes of mortality late following lung transplantation are bronchiolitis obliterans, infections, and malignancy. The development of newer immunosuppressant drugs may offer hope for better results in the future.

Living donor lobar grafts improve pediatric lung retransplantation survival

OBJECTIVE

Lung retransplantation is a controversial practice due to increased morbidity and mortality and the scarcity of available donor organs. Living donor lobar lung transplantation increases the number of available donor organs and facilitates a more organized procedure than traditional cadaveric donation for this complex reoperation. The purpose of this study was to evaluate our experience with pediatric lung retransplantation and to compare the outcomes of living donor lobar lung transplantation with cadaveric donation.

METHODS

Retrospective review of a prospectively collected database identified 39 children who underwent lung retransplantation from 1991 to 2004. Retransplantation was performed with living donor lobar lung transplantation in 13 patients and cadaveric donation in 26 patients. Short- and long-term outcomes were compared between the 2 groups.

RESULTS

Perioperative mortality was 1/13 (7.7%) in the patients who had living donor lobar lung transplantation versus 11/26 (42.3%) in the cadaveric donation group (P = .03). Five-year survival for living donor lobar lung transplantation and cadaveric donation was 40.4% and 29.7%, respectively (P = .27). Both groups had a significant improvement in their forced expiratory volume in 1 second 6 months after retransplantation (P < .001). Multivariate analysis identified the use of cadaveric donation (relative risk = 6.16, P = .001) and early graft dysfunction (relative risk = 6.19, P = .001) as the major independent predictors of decreased survival following retransplantation.

CONCLUSIONS

Living donor lobar lung transplantation reduces perioperative mortality and is an independent predictor of improved survival following pediatric lung retransplantation. This strategy offers significant benefit for this high-risk group and preserves the limited supply of donor lungs for other children at risk of dying while waiting for lung transplantation.

Role of open lung biopsy in lung transplant recipients in a single children’s hospital: A 13-year experience

BACKGROUND

There are few data in the literature regarding the utility of open lung biopsy for the assessment of graft dysfunction after pediatric lung transplantation. The aim of this study is to review our experience with diagnostic open lung biopsy in lung transplant recipients in a children's hospital.

METHODS

Records of lung transplant recipients from January 1990 through December 2002 were reviewed to identify the indications, outcomes, and complications of open lung biopsy.

RESULTS

Two hundred twenty-four patients (mean age, 9.9 +/- 6.2 years; median age, 11 years; age range, 0.01-19.6 years) underwent 249 lung transplantations: 231 bilateral, 8 single, and 10 heart-lung transplantations. Mean follow-up was 3.4 years. One hundred three open lung biopsies were performed in 89 (40% of all recipients) patients. Thirteen recipients underwent open lung biopsy twice, and 1 recipient had 3 open lung biopsies. The indications for open lung biopsy were suspicion of bronchiolitis obliterans (n = 70), posttransplantation lymphoproliferative disorder (n = 15), infection (n = 8), and unexplained respiratory failure (n = 10). A new diagnosis was made in 49 biopsies (48%), 50 biopsies (49%) confirmed the preoperative clinical diagnosis, and 4 biopsies (3%) were nondiagnostic. Bronchiolitis obliterans was confirmed in 40 (57%) of 70 open lung biopsies, posttransplantation lymphoproliferative disorder was confirmed in 4 (27%) of 15 open lung biopsies, and infection was confirmed in 6 (75%) of 8 open lung biopsies. A change in therapy occurred in 69% of the cases as a result of the diagnosis made from open lung biopsy. There was no mortality as a direct result of open lung biopsy. Eleven major complications and 22 minor complications occurred in 103 procedures.

CONCLUSION

Open lung biopsy can be performed safely, and established or confirmed a diagnosis in 97% of the cases. A change in therapy occurred in 69% of the cases as a result of the diagnosis made from open lung biopsy. In our experience open lung biopsy appears to be a useful tool.

Bronchial airway anastomotic complications after pediatric lung transplantation: Incidence, cause, management, and outcome

OBJECTIVE

Airway complications are a recognized surgical complication and an important source of morbidity after adult lung transplantation. Little is known about these complications after pediatric lung transplantation.

METHODS

Data of pediatric lung transplants performed between January 1990 and December 2002 in a single pediatric institution were reviewed retrospectively.

RESULTS

A total of 214 patients, with a mean age of 9.8 +/- 6.1 years (range 0.01-19.7 years), underwent 239 lung transplants: 231 bilateral and 8 single. Mean follow-up was 3.4 years. Forty-two airway complications requiring interventions (stenosis = 36; dehiscence = 4; malacia = 2) developed in 30 recipients (complication rate: 9% of 470 bronchial anastomoses at risk). There were airway complications in 29 bilateral lung transplants (13%) and 1 single lung transplant (13%). Mean time to diagnosis was 51 +/- 27 days (median: 53, range 1-96 days), and diagnoses were made in 90% of patients within the first 3 months after transplantation. Preoperative Pseudomonas cepacia, postoperative fungal lung infection, and days on mechanical ventilator were found to be significant risk factors on multivariate analysis (P = .002, P = .013 and P = .003, respectively). Treatment included rigid bronchoscopic dilatation in 17 patients, balloon dilatation in 13 patients, and stent placement in 12 patients. Other treatments consisted of debridement, fibrin glue application, chest tube placement, and pneumonectomy followed by retransplantation. No patients died as a direct result of airway complications. There was no significant difference in the incidence of bronchiolitis obliterans or overall survival in comparison with patients who did not have airway complications.

CONCLUSIONS

Airway complications are a significant cause of morbidity after pediatric lung transplantation. The majority are successfully treated, and patient outcomes are not adversely affected.

Early outcome after Glenn shunt and Fontan palliation and the impact of operation during viral respiratory season: analysis of a 19-year multi-institutional experience

BACKGROUND

This study was done to investigate the impact of season of operation, age at operation, and surgical era on short-term outcome after single ventricle palliation. One small study suggests that operation during viral respiratory season is associated with prolonged pleural effusion and hospitalization. Single-institution studies also find improved outcomes after the Glenn shunt and Fontan over time, despite operation at a younger age.

METHODS

The Pediatric Cardiac Care Consortium (PCCC) database for Fontan (n = 2,713) and Glenn shunt (n = 2,239) performed between 1982 and 2000 was utilized. Death during initial hospitalization and length of stay after each procedure were investigated. Viral respiratory season was defined as the interval of November to March.

RESULTS

The mortality rate after Fontan was higher during the viral respiratory season (14 versus 11%, p = 0.03) and in children under age 2 years. Glenn shunt mortality was higher with operation before age of 120 days, but was not affected by operation during viral respiratory season. Age at operation for the Fontan procedure has decreased with declines in hospital mortality (14% to 7%, p < 0.0001) and hospital stay (14 to 11 days, p < 0.0001) comparing 1992 to 1995 with 1996 to 2000.

CONCLUSIONS

Fontan procedure performed during viral respiratory season is associated with an increased mortality. Short-term mortality and morbidity after the Glenn and Fontan procedures have improved in the recent era. Operation in the youngest age groups may adversely impact mortality.

Epidemiology of bloodstream infections in the first year after pediatric lung transplantation

BACKGROUND

Substantial morbidity and mortality rates are associated with infections in the first year after pediatric lung transplantation. To understand better the clinical significance of bloodstream infections (BSIs), we evaluated systematically the epidemiologic features of BSIs in the first year after transplantation.

METHODS

A retrospective case-cohort study of pediatric primary lung transplant recipients was performed. The frequency of BSIs and the organisms isolated were determined through medical and laboratory record review. We assessed variations in causative organisms and rates of BSIs in 3 time periods after transplantation, ie, early (0-30 days), intermediate (31-90 days) and late (91-365 days).

RESULTS

Between July 1990 and November 2000, 190 pediatric patients received primary lung transplants. Twenty-six percent (49 of 190) of recipients had at least 1 BSI. The most commonly isolated organisms were coagulase-negative Staphylococcus (n = 25, 28.4%), Pseudomonas aeruginosa (n = 14, 16.0%) and Candida spp. (n = 9, 10.2%). The overall rate of BSIs was 2.1 episodes per 1000 catheter-days. The highest rate of BSIs occurred in the early period, compared with the intermediate and late periods (5.5, 1.3 and 1.6 episodes per 1000 catheter-days, respectively; P = 0.21). Early BSIs were associated with death in the first year after transplantation (relative risk, 3.9; 95% confidence interval, 1.6-9.4; P = 0.002).

CONCLUSIONS

BSIs occur frequently after primary pediatric lung transplantation, with the highest rate being in the first 30 days after transplantation. Early BSIs are associated with death in the first year after transplantation.

Repair of congenital heart lesions combined with lung transplantation for the treatment of severe pulmonary hypertension: A 13-year experience

OBJECTIVE

In patients with severe pulmonary hypertension associated with congenital heart disease, we prefer to perform repair of the congenital heart disease and lung transplantation whenever feasible so as to augment the donor pool and avoid the cardiac complications associated with heart transplantation. We report our experience with repair of congenital heart disease and lung transplantation and compare the results with those of patients who underwent heart-lung transplantation during the same period.

METHODS

The records of patients who had repair of congenital heart disease and lung transplantation (n = 35) and heart-lung transplantation (n = 16) between 1990 and 2003 were reviewed.

RESULTS

The underlying congenital heart disease in the repair of congenital heart disease and lung transplantation group included transposition of great vessels (n = 2), atrioventricular canal defect (n = 2), ventricular septal defect (n = 9), pulmonary venous obstruction (n = 7), scimitar syndrome (n = 2), pulmonary arterial atresia or stenosis (n = 5), and others (n = 8). Thirteen of the patients undergoing repair of congenital heart disease and lung transplantation (37.1%) had the congenital heart disease repaired before lung transplantation; the remaining congenital heart disease repairs were performed concurrently with transplantation. Sixteen patients underwent heart-lung transplantation because of poor left ventricular function or single-ventricle anatomy. Freedoms from bronchiolitis obliterans at 1, 3, and 5 years were 72.9%, 54.7%, and 54.7% for the repair of congenital heart disease and lung transplantation group and 77.8%, 51.9%, and 38.9% for the heart-lung transplantation group, respectively. Survivals at 1, 3, and 5 years were 62.9%, 51.4%, and 51.4% for the repair of congenital heart disease and lung transplantation group and 66.5%, 66.5%, and 60% for the heart-lung transplantation group, respectively.

CONCLUSION

Repair of congenital heart disease and lung transplantation is a feasible treatment option. Long-term outcome is determined by associated complications related to lung transplantation. Despite the complexity of combined congenital heart disease repair with lung transplantation and the resulting perioperative morbidity, the patients had similar outcomes to those of patients who underwent heart-lung transplantation.

Progressive Lung Disease and Surfactant Dysfunction with a Deletion in Surfactant Protein C Gene

Mutations in the surfactant protein (SP)-C gene are responsible for familial and sporadic interstitial lung disease (ILD). The consequences of such mutations on pulmonary surfactant composition and function are poorly understood. To determine the effects of a mutation in the SP-C gene on surfactant, we obtained lung tissue at the time of transplantation from a 14-mo-old infant with progressive ILD. An in-frame 9-bp deletion spanning codons 91-93 in Exon 3 of the SP-C gene was present on one allele; neither parent carried this deletion. SP-C mRNA was present in normal size and amount. By immunofluorescence, proSP-C was aggregated within alveolar Type II cells in a compartment separate from SP-B. In airway surfactant, there was little or no mature SP-B or SP-C; SP-A content was increased. Minimum surface tension was increased (20 mN/m, normal < 5 mN/m). Type II cells contained normal and disorganized appearing lamellar bodies by electron microscopy. This spontaneous deletion on one allele of the SP-C gene was associated with sporadic ILD and abnormalities in surfactant composition and function. We propose that a dominant negative effect on surfactant protein metabolism and function results from aggregation of misfolded proSP-C and subsequent cell injury and inflammation.

Risk factors for primary graft failure after pediatric cardiac transplantation: importance of recipient and donor characteristics

BACKGROUND

Primary graft failure, or circulatory insufficiency immediately after transplantation, frequently occurs after pediatric cardiac transplantation and is the most common cause of death after infant transplantation. Risk factors for pediatric primary graft failure are poorly defined.

METHODS

We retrospectively reviewed donor, procedural and recipient characteristics for primary graft failure in 165 pediatric cardiac transplant recipients (median age at transplant 1.1 years) by multivariatle logistic regression. Primary graft failure was defined as the need for mechanical circulatory support or use of multiple intravenous inotrope/pressors, including epinephrine, for circulatory support within the first 24 hours after transplantation.

RESULTS

Primary graft failure occurred in 54 patients (33%); 24 patients (15%) required mechanical support for their graft failure; and primary graft failure was the cause of death or graft loss in 10 patients. Recipient risk factors associated with an increased risk of primary graft failure included diagnosis of congenital heart disease and a need for mechanical support before transplantation. Ventilator support before transplantation and maximal pulmonary vascular resistance index were risk factors for the development of isolated right ventricular graft failure. Donor risk factors associated with an increased risk for primary graft failure included increasing donor recipient weight and body surface area ratios; increasing donor ischemic time; anoxia as a cause of death; and increasing cardiopulmonary resuscitation time. Donor blood type O+ and hyperdynamic donor systolic function were associated with a decreased risk of primary graft failure.

CONCLUSIONS

Multiple donor, recipient and procedural risk factors, including the type and severity of heart disease in the recipient before transplantation, are associated with primary graft failure after pediatric cardiac transplantation. Avoidance of matching high-risk donors to high-risk recipients may improve morbidity and mortality after transplantation.

Non-ischemic left ventricular dysfunction after pediatric cardiac transplantation: treatment with plasmapheresis and OKT3

BACKGROUND

Acquired left ventricular dysfunction after pediatric cardiac transplantation is associated with a high mortality rate. It often occurs without biopsy evidence of cellular rejection or severe transplant coronary arteriopathy.

METHODS

We employed a protocol for treatment of acquired, non-ischemic left ventricular dysfunction utilizing plasmapheresis, monoclonal anti-T-cell antibody (OKT3), cyclophosphamide and steroids, regardless of the results of endomyocardial biopsy. Left ventricular dysfunction was defined as an echocardiographic shortening fraction of <29% and/or symptoms of congestive heart failure requiring inotropic support. Transplant coronary arteriopathy was excluded by coronary angiography in all cases.

RESULTS

Ten pediatric heart transplant recipients were treated for 13 episodes of non-ischemic left ventricular dysfunction. Biopsy scores were low grade (ISHLT Grade 1A or 1B) in 8 episodes. Eight of 10 patients had a history of non-compliance in regularly taking immunosuppressant medications. Inotropic support was required in 9 of 13 cases, with a median duration of 5 days. Median left ventricular shortening fraction was 17% at time of presentation. Normalization of shortening fraction occurred a median of 40 days from the start of treatment. Survival to hospital discharge occurred in 11 of 13 (85%) patients. Long-term patient survival, however, was only 50% at 24 months after presentation with a first episode of acquired left ventricular dysfunction.

CONCLUSIONS

Use of plasmapheresis, OKT3, cyclophosphamide and steroids resulted in successful short-term reversal of non-ischemic left ventricular dysfunction in pediatric heart transplant patients, but long-term survival remained poor.

Mediastinal wound infections following pediatric cardiac surgery

Deep sternal wound infections in children and neonates occur at approximately the same incidence as in adults. The organisms responsible are generally Staphylococcal species. The risk factors in adults include diabetes mellitus, the use of internal mammary artery grafts for bypass conduits, and other factors which clearly relate to age and the nature of the operations performed. In children the risk factors include leaving the sternum open following repair, nasal colonization with Staphylococcal species, need for re-exploration for bleeding, and others. Although conventional therapy for this complication is similar to what is proposed for adults, recently interest has been established in treating with debridement and primary closure of the sternum.

Have we met the expectations of heart and lung transplantation in children?

Heart transplantation in children has been a relatively common practice for more than 15 years, and lung transplantation, while in use as a therapeutic modality for a shorter period of time, has 10 years of follow-up data for review. Because they are expensive, time-consuming, labor-intensive procedures, it is reasonable to review what has transpired to evaluate the effectiveness of these procedures, not only from the standpoint of survival, but in the applicability and availability to all who need it, and successful long-term outcomes including quality of life in those who receive it. Health care expense can be justified by improved results that reach expectations in the areas of applicability, availability, and survival. The applicability issue has, in large part, been achieved in transplantation in children. The goal of comprehensive availability can be met by providing alternatives to transplantation, advancing artificial organ research, and overhauling the organ donor programs to improve organ retrieval. To better meet expectations for survival, further advances in transplant immunology and solutions to the problems of post-transplant coronary artery disease and bronchiolitis obliterans will have to occur.

Cytomegalovirus viremia associated with death or retransplantation in pediatric lung-transplant recipients

BACKGROUND

Cytomegalovirus (CMV) infection is a frequent complication of lung transplantation. However, there is limited information regarding the incidence and sequelae of CMV infections in pediatric lung-transplant recipients. On the basis of case series suggesting that CMV infection was associated with excess morbidity and mortality in lung-transplant recipients, we hypothesize that CMV viremia increases the risk of bronchiolitis obliterans (BOS) or death and retransplantation in the first year following transplantation.

METHODS

A case-cohort study of pediatric primary lung-transplant recipients was performed. Univariate analysis was used to assess whether CMV viremia was associated with BOS or death and retransplantation within 1 year after transplantation. Patients at high risk for CMV infection received ganciclovir prophylaxis for 42 days posttransplantation.

RESULTS

From July 1990 to November 2000, 194 pediatric patients received primary lung transplants. Twenty-three percent of patients developed CMV viremia. Eighty percent of CMV viremia episodes occurred before 120 days posttransplant. A first episode of CMV viremia was associated with retransplantation or death between days 90 and 365 (RR=4.1, 95% confidence interval [CI] 1.1-14.5) and was not associated with BOS (RR=1.3, 95% CI 0.5-3.3).

CONCLUSIONS

CMV viremia in the first year after pediatric primary lung transplantation is associated with increased risk of death or retransplantation between 90 and 365 days posttransplant, when CMV prophylaxis has stopped. A phase II pilot trial is warranted to assess safety and short-term efficacy of increasing the duration of CMV prophylaxis from 42 to 120 days.

Lung transplantation in children following treatment for malignancy

BACKGROUND

End-stage lung disease is a rare complication of treatment for hematologic and solid tumors in children. When present, it is generally progressive, resulting in the patient being cured of cancer only to die of respiratory failure. Lung transplantation is believed by some to be of overly high risk in this population because of the pre-existing malignancy as well as the presumed compromised immune status.

METHODS

Six children (Group 1), aged 5 to 17 years (mean 12.4 years), underwent lung transplantation at our institution because of either pulmonary fibrosis or bronchiolitis obliterans following treatment for acute leukemia (n = 5) or medulloblastoma (n = 1). All patients received chemotherapy, radiation and bone marrow transplantation in the course of treatment for their malignancies. The average forced expiratory volume in 1 second (FEV(1)) was 16% of the predicted value and forced vital capacity (FVC) was 28% of predicted. These results were compared with a similar group of 13 patients undergoing lung transplantation at our institution during the same time interval (Group 2).

RESULTS

There were 2 deaths in Group 1, 1 early and 1 late, for an overall survival of 67% at a mean follow-up of 4.02 years. There were no early and 7 late deaths in Group 2 for an overall survival of 46% at a mean follow-up of 4.8 years. The acute rejection rate in the first post-transplant year was 0.2 episode/patient in Group 1 and 1.8 episode/patient in Group 2 (p <0.01). No patient in Group 1 has developed post-transplant lymphoproliferative disease or a relapse of their primary malignancy. Two patients in Group 1 developed unusual infections-Aspergillus and Mycobacterium chelonae. No such infections occurred in Group 2.

CONCLUSIONS

Although this represents a small series, we believe that patients with respiratory failure following treatment of a prior malignancy are suitable candidates for lung transplantation. Although they may have some relative protection from acute rejection episodes by virtue of an already compromised immunologic status while receiving standard immunosuppression, an increased propensity for opportunistic infection may exist.