The Failed Bidirectional Glenn Shunt: Risk Factors for Poor Outcomes and the Role of Early Reoperation

Background: Bidirectional Glenn shunt (BDG) failure carries high morbidity and mortality but the clinical factors associated with failure and the optimal management strategy are understudied. Methods: A total of 217 patients undergoing BDG at our institution between 1989 and 2020 were retrospectively reviewed and categorized as success or failure. Failure was defined as the need for reoperation (BDG takedown, reoperation for correction of cardiac defect, and/or transplantation) at any time postoperatively; operative mortality (death attributable to BDG malfunction occurring during the index hospitalization for BDG or within 30 days of discharge); or late mortality (death directly attributable to BDG malfunction occurring prior to Fontan or next-stage palliation). Univariate and binary logistic regression analyses were performed. Results: BDG failure occurred in 14 (6.5%) patients. Univariate predictors were: hypoplastic left heart syndrome (P = .037), right ventricular (RV) dominance (P = .010), greater pre-BDG pulmonary vascular resistance (PVR) (P = .012), concomitant atrioventricular valve repair (P = .020), prolonged pleural drainage (P = .001), intensive care unit (P<.001) and hospital (P = .002) stays, and extracorporeal membrane oxygenation (ECMO) requirement (P<.001). Multivariate predictors were: RV dominance (P = .002), greater PVR (P = .041), ICU (P<.001) and hospital (P = .020) stays, and need for ECMO (P<.001). As many as 10 of 14 (71%) patients with BDG failure died. Reoperation was performed for 10 patients with BDG failure. Five reoperation patients survived until discharge, with four patients alive at last follow-up (mean 7.9 years). Survivors underwent reoperation earlier than nonsurvivors (36 vs. 94 days). Conclusions: BDG failure carries high mortality, but preoperative predictors and postoperative indicators of failure exist. Early BDG takedown and insertion of aorta-pulmonary shunt may allow survival.

A novel mutation of the MYH7 gene in a patient with hypertrophic cardiomyopathy

Goel N, Huddleston CB, Fiore AC. A novel mutation of the MYH7 gene in a patient with hypertrophic cardiomyopathy. Turk J Pediatr 2018; 60: 315-318. Hypertrophic cardiomyopathy (HCM) is a genetic disorder characterized by asymmetric cardiac hypertrophy due to inherited mutations in genes that encode sarcomeric proteins. MYH7, which encodes β-myosin heavy chain, is among the most commonly mutated genes in patients affected by HCM. We aimed to identify the specific mutation responsible for HCM in a six-month old Caucasian patient. NextGen DNA sequencing revealed a novel p.Ala1328Thr (A1328T) mutation of MYH7 in the affected patient as well as his asymptomatic father and asymptomatic brother. The clinical details of this mutation are described for the first time in this report. The genetic variant affects a residue that is highly conserved across species. Theoretical analysis suggests that A1328T is very likely deleterious to β-myosin heavy chain protein structure and function. Furthermore, this novel mutation was not observed with any significant frequency in approximately 6,500 healthy individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, underlining the potential pathogenicity of this variant.

Complications Associated With Implantable Cardioverter Defibrillators in Adults With Congenital Heart Disease or Left Ventricular Noncompaction Cardiomyopathy (From the NCDR® Implantable Cardioverter-Defibrillator Registry)

Patients with childhood heart disease are living longer and entering adulthood, and may undergo implantable cardioverter-defibrillator (ICD) implantation to reduce the risk of sudden death. We evaluated the characteristics of adult patients with congenital heart disease or left ventricular noncompaction cardiomyopathy (LVNC) in the National Cardiovascular Disease Registry ICD Registry and determined ICD-related in-hospital complications. Patients with LVNC or transposition of the great arteries, tetralogy of Fallot, Ebstein's anomaly, atrial septal defect, ventricular septal defect, or common ventricle were identified in the registry. In-hospital complications were compared among different diagnoses using the chi-square test for categorical variables and the F-test in analyses of variance for continuous variables. A total of 3,077 patients were identified. The mean age was 48.0 ± 16.0 years, and 39.9% were female. Single-chamber ICDs were implanted in 25.2%, dual chamber in 41.9%, and cardiac resynchronization in 30.8%. Intraprocedural or postprocedural complications occurred in 70 patients (2.3%); there were 6 in-hospital deaths (0.2%). The most frequent complications were acute lead dislodgments, pneumothorax, and hematomas. Patients with Ebstein's anomaly had the greatest complication rate (8.3%, p = 0.03). The complication rate was 1.55% in single-chamber devices, 1.86% in dual chamber, and 3.5% in cardiac resynchronization (p < 0.001). For initial implants, the complication rate was 2.55%, 1.62% in generator replacements, and 8.77% in lead revisions (p = 0.001). In conclusion, in this large contemporary adult cohort of congenital heart disease and LVNC patients who underwent ICD implant procedures, periprocedural complication rates were low. Lead-related risks predominated.

Heart transplantation in children with intellectual disability: An analysis of the UNOS database

Heart transplantation in children with intellectual disability (ID) is an issue of debate due to the shortage of available donor organs. We sought to perform the first large-scale retrospective cohort study describing the prevalence and outcomes of heart transplantation in this population. The United Network of Organ Sharing database was queried from 2008 to 2015 for pediatric patients (age <19 years) receiving first, isolated heart transplant. Recipients were divided into three subgroups: definite ID, probable ID, and no ID. The chi-square test was used to compare patients' baseline characteristics. Kaplan-Meier and Cox proportional hazard regression analyses were used to estimate the association between ID and death-censored graft failure and patient survival. Over the study period, 565 pediatric patients with definite (131) or probable (434) ID received first heart transplant, accounting for 22.4% of all first pediatric heart transplants (n=2524). Recipients with definite ID did not significantly differ from those without ID in terms of gender, ethnicity, ischemia time, severity of pretransplant condition (waitlist status, mechanical ventilation, inotrope dependence, ECMO, VAD, PVRI, infection prior to transplant), or incidents of acute rejection within the first year. ID was associated with prolonged waitlist time (P<.001). Graft and patient survival at 3 years was equivalent between children with and without ID (P=.811 and .578, respectively). We conclude that intellectual disability is prevalent in children receiving heart transplants, with 22.4% of recipients over the study period having definite or probable ID. ID does not appear to negatively affect transplantation outcomes. Future studies are needed to assess long-term outcomes of transplantation in this population.

Recommendations for utilization of the paracorporeal lung assist device in neonates and young children with pulmonary hypertension

The management of decompensating critically ill children with severe PH is extremely challenging and requires a multidisciplinary approach. Unfortunately, even with optimal care, these children might continue to deteriorate and develop inadequate systemic perfusion and at times cardiac arrest secondary to a pulmonary hypertensive crisis. Tools to support these children are limited, and at times, the team should proceed with offering extracorporeal support, especially in newly diagnosed patients who have not benefitted from medical therapy prior to their acute deterioration, in patients with severe pulmonary venous disease and in patients with alveolar capillary dysplasia. Currently, the only approved mode for extracorporeal support in pediatric patients with PH eligible for lung transplantation is ECMO. To decrease the risks associated with ECMO, and offer potential for increased duration of support, extubation, and rehabilitation, we transitioned four small children with refractory PH from ECMO to a device comprising an oxygenator interposed between the PA and LA. This work describes in great detail our experience with this mode of support with emphasis on exclusion criteria, the implantation procedure, and the post-implantation management.

Repair of Anomalous Aortic Origin of a Coronary Artery in 113 Patients

Background:

Anomalous aortic origin of a coronary artery (AAOCA) encompasses a wide morphologic spectrum, which has impeded consensus regarding indications for the diverse repair strategies. We constructed a profile of current surgical techniques and explore their application to morphologic variants.

Methods:

Patients <30 years old (n = 113) with isolated AAOCA who underwent operations at 29 Congenital Heart Surgeons Society (CHSS) institutions from 1998 to 2012 were identified from the CHSS AAOCA Registry. Operative findings were related to surgical techniques at index repairs by cross-tabulation.

Results:

Anomalous origin of the left main or left anterior descending coronary artery was present in 33 (29%) patients and of the right coronary artery in 78 (69%) patients; 2 arteries originated directly above the commissure between the left and right sinuses. There were 101 (89%) interarterial and intramural (IA/IM) arteries, 10 (9%) were interarterial but not intramural (IA/NIM) and 2 (2%) were neither interarterial nor intramural. Intramural arteries were unroofed in 100 (88%) operations, usually with intimal tacking after incision (n = 47) or excision (n = 25) of the common wall. Coronary reimplantation (n = 11), pulmonary artery relocation (n = 7; 5 for IA/NIM), simple ostioplasty (without unroofing; n = 3), coronary artery bypass grafting (n = 2), and ostial window (n = 1) were less common. In 37 (33%) operations, a valvar commissure was taken down; 33 were resuspended.

Conclusion:

Current surgical repair of AAOCA is individualized to morphology, particularly the presence of intramural and/or interarterial segments. This report is foundational for future planned CHSS studies that will examine interventional and noninterventional outcomes and ultimately guide management of AAOCA.

Heart-lung transplantation

Heart-lung transplantation itself is not a particularly difficult operation technically. It is the setting in which this procedure is performed which is difficult. The three issues of importance in a successful outcome are appropriate harvest of the heart-lung bloc from the donor, careful explant of the heart and lungs of the recipient, and finally the implant of the heart-lung bloc into the recipient. None of this requires extraordinary technical skill, but does require careful coordination and planning as well as adhering to some fundamental principles. One of the major pitfalls encountered is bleeding related to the explant procedure. Another is graft failure related to harvest and/or the implant procedure. The third is injury to either the phrenic nerve(s) or the left recurrent laryngeal nerve related to the explant procedure. Heart-lung transplantation is a major investment in resources of all sorts including financial, personnel, as well as the organs themselves. It is absolutely imperative that this procedure be performed only by experienced surgeons in centers with established expertise.

Apical Aortic Conduit Infection 27 Years After Repaired Left Ventricular Outflow Tract Obstruction

Left ventricle to aortic conduits were used for the treatment of complex left ventricular outflow tract obstruction in the pediatric population in the mid-1970s. Although this technique has been largely replaced by the Ross-Konno procedure, many patients still have functioning apicoaortic conduits in place today. Few clinical reports or case series exist in pediatric cohorts documenting the natural history or potential long-term complications of this prosthesis. In this report, we describe our experience managing a patient with Shone's syndrome and an apical aortic porcine-valved conduit remnant that became infected 17 years postconduit valve excision for valvular insufficiency.

Hybrid versus Norwood procedure for hypoplastic left heart syndrome: contemporary series from a single center

OBJECTIVE

Two different strategies have emerged in the initial palliation for hypoplastic left heart syndrome, the conventional Norwood operation and the so-called hybrid procedure. We have used each of these at our center. The purpose of the present study was to compare the outcomes of both procedures.

METHODS

From 2007 to 2012, 40 patients presented to the Cardinal Glennon Children's Medical Center with hypoplastic left heart syndrome or 1 of its variants. Of the 40 patients, 24 underwent a hybrid procedure and 16 a Norwood procedure for initial palliation. The medical records, echocardiograms, and cardiac catheterization data were retrospectively reviewed. Standard statistical analysis was performed.

RESULTS

The patients who underwent the hybrid procedure weighed less than those who underwent the Norwood procedure. Overall unadjusted survival was better in the Norwood group, although this did not reach statistical significance. Overall hospital resource usage was similar in both cohorts, taking into account both first and second palliation stages.

CONCLUSIONS

In our review, we found no statistically significant difference in survival or resource usage between those patients undergoing the Norwood procedure and those undergoing a hybrid procedure as initial palliation for hypoplastic left heart syndrome.

A multicenter study of primary graft failure after infant heart transplantation: impact of extracorporeal membrane oxygenation on outcomes

Primary graft failure is the major cause of mortality in infant HTx. The aim of this study was to characterize the indication and outcomes of infants requiring ECMO support due to primary graft failure after HTx. We performed a retrospective review of all infants (<1 yr) who underwent Htx from three institutions. From 1999 to 2008, 92 infants (<1 yr) received Htx. Sixteen children (17%) required ECMO after Htx due to low cardiac output syndrome. Eleven (69%) infants were successfully weaned off ECMO, and 9 (56%) infants were discharged with a mean follow-up of 2.3 ± 2.5 yr. Mean duration of ECMO in survivors was 5.4 days (2-7 days) compared with eight days (2-10 days) in non-survivors (p = NS). The five-yr survival rate for all patients was 75%; however, the five-yr survival rate was 40% in the ECMO cohort vs. 80% in the non-ECMO cohort (p = 0.0001). Graft function within one month post-Htx was similar and normal between ECMO and non-ECMO groups (shortening fraction = 42 ± 3 vs. 40 ± 2, p = NS). For infants, ECMO support for primary graft failure had a lower short-term and long-term survival rate vs. non-ECMO patients. Duration of ECMO did not adversely impact graft function and is an acceptable therapy for infants after HTx for low cardiac output syndrome.

Paracorporeal lung assist devices as a bridge to recovery or lung transplantation in neonates and young children

OBJECTIVE

To evaluate paracorporeal lung assist devices to treat neonates and children with decompensated respiratory failure as a bridge to recovery or lung transplantation.

METHODS

One neonate (23 days old) and 3 young children (aged 2, 9, and 23 months) presented with primary lung disease with pulmonary hypertension, including alveolar capillary dysplasia in 2 and right pulmonary hypoplasia and primary pulmonary hypertension in 1. The patients were listed for lung transplantation but decompensated and required extracorporeal membrane oxygenation (ECMO). The patients were transitioned from ECMO to a pumpless paracorporeal lung assist device (Maquet Quadrox-iD oxygenator in 3, Novalung in 1) with inflow from the pulmonary artery and return to the left atrium.

RESULTS

The patients were weaned from ECMO and supported by the device for 44 ± 29 days (range, 5-74). Three patients were extubated while supported by the device (after 9, 15, and 72 days). One patient was bridged to lung transplant (9 months old, with alveolar capillary dysplasia, supported 5 days). One patient was bridged to recovery with maximal medical therapy (23 months old, with primary pulmonary hypertension, supported 23 days). Two patients died while awaiting a suitable lung donor after a support time of 54 and 72 days.

CONCLUSIONS

Pediatric patients bridged from ECMO to lung transplantation have poor results. An alternative method for longer term respiratory support was necessary as a bridge for these patients. The use of a paracorporeal lung assist device successfully supported 4 patients to recovery, lung transplantation, or past the average wait time for pediatric donor lungs (27 days). This therapy has the potential to bridge children with decompensated respiratory failure to lung transplantation.

Heart transplantation in biventricular congenital heart disease: indications, techniques, and outcomes

Heart transplantation is an accepted therapeutic modality for end-stage congenital heart disease for both biventricular and univentricular anomalies. Many transplant centers have pushed the limits of transplantation to include patients with high pulmonary vascular resistance, high panel reactive antibodies, positive cross-matches, and ABO-incompatibility. Excellent results have been possible, particularly with the development of improved diagnostic and therapeutic algorithms to prevent and treat rejection, infection, and post-transplant lymphoproliferative disease. Late graft failure and chronic rejection remain vexing problems. The vast majority of patients with biventricular congenital heart disease have undergone prior cardiac surgical procedures. Indications for transplantation in this subgroup are primarily progressive refractory heart failure following prior cardiac surgical reconstructive procedures. Contraindications to transplantation mimic those for other forms of end-stage heart disease. A determination of pulmonary vascular resistance is important in listing patients with biventricular congenital heart disease for heart transplantation. Modifications in the implant technique are necessary and vary depending on underlying recipient anatomy. Risk factors for perioperative outcomes in patients with biventricular congenital heart disease include the need for reoperation, the degree of anatomic reconstruction necessary during the implant procedure, and the degree of antibody sensitization, in addition to a number of other recipient and donor factors. Postoperative outcomes and survival are very good but remain inferior to those with cardiomyopathy in most series. In conclusion, patients with end-stage biventricular congenital heart disease represent a complex group of patients for heart transplantation, and require careful evaluation and management to ensure optimal outcomes.

Lung transplantation for pulmonary fibrosis in dyskeratosis congenita: Case Report and systematic literature review

Background

Dyskeratosis congenita (DC) is a progressive, multi-system, inherited disorder of telomere biology with high risks of morbidity and mortality from bone marrow failure, hematologic malignancy, solid tumors and pulmonary fibrosis. Hematopoietic stem cell transplantation (HSCT) can cure the bone marrow failure, but it does not eliminate the risks of other complications, for which life-long surveillance is required. Pulmonary fibrosis is a progressive and lethal complication of DC.

Case presentation

In this report, we describe a patient with DC who developed pulmonary fibrosis seven years after HSCT for severe aplastic anemia, and was successfully treated with bilateral lung transplantation. We also performed a systematic literature review to understand the burden of pulmonary disease in patients with DC who did or did not receive an HSCT. Including our patient, we identified 49 DC patients with pulmonary disease (12 after HSCT and 37 without HSCT), and 509 with no reported pulmonary complications.

Conclusion

Our current case and literature review indicate that pulmonary morbidity is one of the major contributors to poor quality of life and reduced long-term survival in DC. We suggest that lung transplantation be considered for patients with DC who develop pulmonary fibrosis with no concurrent evidence of multi-organ failure.

Lung transplantation in children with idiopathic pulmonary arterial hypertension: an 18-year experience

BACKGROUND

The natural history of idiopathic pulmonary arterial hypertension (IPAH) in patients of all ages is one of relentless progression. For those who fail medical therapy, lung transplantation remains the ultimate palliation. In the USA, IPAH is the second leading indication for lung transplantation in children and first for children 1 to 5 years of age. In this study, we report our 18-year experience with lung transplantation in children with IPAH.

METHODS

We performed a retrospective chart review of children with IPAH listed for lung transplant at our center between 1991 and 2009. Our data reflect a total of 26 children ranging in age from 1.6 to 18.9 years. Nineteen were transplanted and 7 died while waiting (27%). The impact of a number of pre-transplant variables on survival was evaluated.

RESULTS

Median survival for those transplanted was 5.8 years, with 1- and 5-year survival rates of 95% and 61%, respectively. Survival was independent of pre-transplant considerations such as age, weight, need for intravenous (IV) inotropes, use of IV pulmonary vasodilators, year of transplant and severity of right-sided cardiac pressures. There was 1 hospital death. Compared with the transplanted group, children who died waiting had a significantly higher incidence of supra-systemic right heart pressures (p = 0.02) and hemoptysis (p = 0.01).

CONCLUSIONS

Our study is the largest to date to look at outcomes for lung transplantation in children with IPAH. Their median survival compares favorably with that of all pediatric lung transplant recipients, 5.8 years vs 4.5 years, respectively. We did not identify any pre-transplant variables that presaged a poorer outcome. Thus, survival seemed more related to factors that influence long-term outcomes in all transplant recipients such as rejection and infection. Lung transplantation remains a viable option for children with IPAH, especially for those with supra-systemic right heart pressures despite maximal medical therapy.

Hypoplastic left heart associated with scimitar syndrome

A child with the unique combination of hypoplastic left heart syndrome (HLHS) and scimitar syndrome is presented. Her HLHS was diagnosed in utero, and her scimitar syndrome was discovered during her immediate newborn period. She underwent a successful Norwood operation complicated by supraventricular tachycardia given her Wolf-Parkinson-White syndrome. She has also undergone successful Glenn shunt and at this writing is thriving.

Lung transplantation in infants and toddlers from 1990 to 2004 at St. Louis Children's Hospital

In a retrospective, single-center cohort study, outcomes of infants and toddlers undergoing lung transplant at St. Louis Children's Hospital between 1990 and 2004 were compared to older children. Patients with cystic fibrosis (exclusively older children) and those who underwent heart-lung, liver-lung, single lung or a second transplantation were excluded from comparisons. One hundred nine lung transplants were compared. Thirty-six were in infants <1 year old, 26 in toddlers 1-3 years old and 47 in children >3 years old. Graft survival was similar for infants and toddlers (p = 0.35 and p = 0.3, respectively) compared to children over 3 years old at 1 and 3 years after transplant. Significantly more infants (p < 0.0001 and p = 0.003) and toddlers (p = 0.002 and p = 0.03) were free from acute rejection and bronchiolitis obliterans compared to older patients. While most infants and toddlers had only minimal lung function impairment, and achieved normal to mildly delayed developmental scores, somatic growth remained depressed 5 years after transplant. Lung transplantation in infants and young children carries similar survival rates to older children and adults. Further insights into the unique immunologic aspects of this group of patients may elucidate strategies to prevent acute and chronic rejection in all age groups.

Biventricular assist devices as a bridge to heart transplantation in small children

BACKGROUND

Experience with the use of biventricular assist device (BiVAD) support to bridge small children to heart transplantation is limited.

METHODS AND RESULTS

We used BIVAD support (Berlin EXCOR) in 9 pediatric heart transplant candidates from 4/05 to 7/07. The median patient age was 1.7 years (12 days to 17 years). The median patient weight was 9.4 kg (3 to 38 kg). All children were supported with multiple intravenous inotropes+/-mechanical ventilation (6) or ECMO (3) before BiVAD implantation. All had significant right ventricular dysfunction. The median pulmonary vascular resistance index (Rpi) was 6.0 WU/m(2). Eight patients were successfully bridged to heart transplantation after a median duration of BiVAD support of 35 days (1 to 77 days). One death occurred after 10 days of support from perioperative renal failure in a 3 kg infant. Five patients required at least 1 blood pump change. One patient had a driveline infection requiring treatment. There were no acute neurological complications, no thromboembolic events, and no bleeding complications. In 2 patients with Rpi >10 WU/m(2) unresponsive to pulmonary vasodilator therapy, Rpi dropped to 1.4 and 4.6 WU/m(2), after 33 and 41 days of support, respectively. All 8 survivors underwent successful heart transplantation. Of 5 patients supported >30 days, 3 developed an extremely elevated (>90%) panel reactive antibody by ELISA that was not confirmed by other methods; none had a positive donor-specific retrospective crossmatch. There was 1 episode of rejection (with hemodynamic compromise) in the 8 transplanted patients. Rpi was normal (<3 WU/m(2)) without pulmonary vasodilators in all patients within 3 months after transplant. There have been no deaths after transplant with a median follow-up of 19 months.

CONCLUSIONS

BiVAD support can effectively be used in small children as a bridge to heart transplantation and can be accomplished with low mortality and morbidity. BiVAD support may offer an additional means to reverse extremely elevated pulmonary vascular resistance. Surveillance for HLA antibody sensitization during BiVAD support may be complicated by the development of non-HLA antibodies which may not reflect true HLA presensitization.

Infectious, malignant, and autoimmune complications in pediatric heart transplant recipients

OBJECTIVE

To review clinical courses of pediatric heart transplant survivors after 5 years from transplantation for infections, lymphoproliferative, and autoimmune diseases.

STUDY DESIGN

A total of 71 patients were examined in 2 groups, infant recipients (underwent transplant <1 year of age, n = 38) and older recipients (underwent transplant >1 year, n = 33). All patients received comparable immunosuppression. Calculated occurrence rates were reported as means per 10 years of follow-up with SEs. Differences were examined by using Poisson regression.

RESULTS

Infant recipients had significantly higher (P < .001) occurrence rates of severe (mean, 2.04 +/- 0.5) and chronic infections (mean, 4.58 +/- 0.67) compared with older recipients (means, 0.37 +/- 0.19 and 1.87 +/- 0.70, respectively). Types of infections were similar to those in the general population with extremely rare opportunistic infections; however, they were more severe and resistant to treatment. Autoimmune disorders occurred at a frequency comparable with lymphoproliferative diseases and were observed in 7 of 38 infants (18%). Most common were autoimmune cytopenias.

CONCLUSIONS

Infant heart transplant recipients who survive in the long term have higher occurrence rates of infections compared with older recipients. Autoimmune disorders are a previously unrecognized morbidity in pediatric heart transplantation.