Association between balloon atrial septostomy and prostaglandin E1 therapy until repair of transposition of the great arteries in neonates.

In patients with transposition of the great arteries, the continuation of prostaglandin E1 is more frequent in patients with intact ventricular septum in comparison to patients with ventricular septal defect. Ballon atrial septostomy did not eliminate the need for prostaglandin E1 infusion until the time of surgery in both subgroups of patients.

Hybrid Interventions for Pulmonary Vein Stenosis: Leveraging Intraoperative Endovascular Adjuncts in Challenging Clinical Scenarios.

Background: Pediatric pulmonary vein stenosis (PVS) is often progressive and treatment-refractory, requiring multiple interventions. Hybrid pulmonary vein interventions (HPVIs), involving intraoperative balloon angioplasty or stent placement, leverage surgical access and customization to optimize patency while facilitating future transcatheter procedures. We review our experience with HPVI and explore potential applications of this collaborative approach. Methods: Retrospective chart review of all HPVI cases between 2009 to 2023. Results: Ten patients with primary (n = 5) or post-repair (n = 5) PVS underwent HPVI at median age of 12.7 months (range 6.6 months-9.5 years). Concurrent surgical PVS repair was performed in 7/10 cases. Hybrid pulmonary vein intervention was performed on 17 veins, 13 (76%) with prior surgical or transcatheter intervention(s). One patient underwent intraoperative balloon angioplasty of an existing stent. In total, 18 stents (9 bare metal [5-10 mm diameter], 9 drug eluting [3.5-5 mm diameter]) were placed in 16 veins. At first angiography (median 48 days [range 7 days-2.8 years] postoperatively), 8 of 16 (50%) HPVI-stented veins developed in-stent stenosis. Two patients died from progressive PVS early in the study, one prior to planned reintervention. Median time to first pulmonary vein reintervention was 86 days (10 days-2.8 years; 8/10 patients, 13/17 veins). At median survivor follow-up of 2.2 years (2.3 months-13.1 years), 1 of 11 surviving HPVI veins were completely occluded. Conclusions: Hybrid pulmonary vein intervention represents a viable adjunct to existing PVS therapies, with promising flexibility to address limitations of surgical and transcatheter modalities. Reintervention is anticipated, necessitating evaluation of long-term benefits and durability as utilization increases.

Pre-Fontan Assessment Utilizing Combined Cardiac Catheterization and Cardiac MRI: Comparison to the Pre-Fontan Catheterization.

Single ventricle patients eligible for Fontan completion undergo pre-Fontan catheterization for hemodynamic and anatomic assessment prior to surgery. Cardiac magnetic resonance imaging may be used to evaluate pre-Fontan anatomy, physiology, and collateral burden. We describe our center's outcomes in patients undergoing pre-Fontan catheterization combined with cardiac magnetic resonance imaging. A retrospective review of patients undergoing pre-Fontan catheterization from 10/2018 to 04/2022 at Texas Children's Hospital was performed. Patients were divided into 2 groups: combined cardiac magnetic resonance imaging and catheterization (combined group) and those who underwent catheterization only (catheterization only group). There were 37 patients in the combined group and 40 in the catheterization only group. Both groups were similar in age and weight. Patients undergoing combined procedures received less contrast, and experienced less in-lab time, fluoroscopy time and catheterization procedure time. Median radiation exposure was lower in the combined procedure group but was not statistically significant. Intubation and total anesthesia times were higher in the combined procedure group. Patients undergoing a combined procedure were less likely to have collateral occlusion performed than in the catheterization only group. Bypass time, intensive care unit length of stay, and chest tube duration were similar in both groups at the time of Fontan completion. Combined pre-Fontan assessment decreases catheterization procedure and fluoroscopy time associated with cardiac catheterization at the expense of longer anesthetic times, and results in similar Fontan outcomes compared to when cardiac catheterization alone is utilized.

Fetoscopic Balloon Dilation and Stent Placement of Congenital High Airway Obstruction Syndrome Leading to Successful Cesarean Delivery.

INTRODUCTION: Without fetal or perinatal intervention, congenital high airway obstruction syndrome (CHAOS) is a fatal anomaly. The ex utero intrapartum treatment (EXIT) procedure has been used to secure the fetal airway and minimize neonatal hypoxia but is associated with increased maternal morbidity. CASE PRESENTATION: A 16-year-old woman (gravida 1, para 0) was referred to our hospital at 31 weeks gestation with fetal anomalies, including echogenic lungs, tracheobronchial dilation, and flattened diaphragms. At 32 weeks, fetoscopic evaluation identified laryngeal stenosis, which was subsequently treated with balloon dilation and stent placement. The patient developed symptomatic and regular preterm contractions at postoperative day 7 with persistent sonographic signs of CHAOS, which prompted a repeat fetoscopy with confirmation of a patent fetal airway followed by Cesarean delivery under neuraxial anesthesia. Attempts to intubate through the tracheal stent were limited and resulted in removal of the stent. A neonatal airway was successfully established with rigid bronchoscopy. Direct laryngoscopy and bronchoscopy confirmed laryngeal stenosis with a small tracheoesophageal fistula immediately inferior to the laryngeal stenosis and significant tracheomalacia. A tracheostomy was then immediately performed for anticipated long-term airway and pulmonary management. The procedures were well tolerated by both mom and baby. The baby demonstrated spontaneous healing of the tracheoesophageal fistula by day of life 7 with discharge home with ventilator support at 3 months of life. CONCLUSION: Use of repeated fetoscopy in order to relieve fetal upper airway obstruction offers the potential to minimize neonatal hypoxia, while concurrently decreasing maternal morbidity by avoiding an EXIT procedure. Use of the tracheal stent in CHAOS requires further investigation. The long-term reconstruction and respiratory support of children with CHAOS remain challenging.

Heart Transplantation for Pediatric and Congenital Cardiac Disease: A Comparison of Two Eras over 23 Years and 188 Transplants at a Single Institution.

BACKGROUND: To assess changes in patterns of practice and outcomes over time, we reviewed all patients who underwent heart transplantation (HTx) at our institution and compared two consecutive eras with significantly different immunosuppressive protocols (cohort 1 [80 HTx, June 1995-June 2006]; cohort 2 [108 HTx, July 2006-September 2018]). METHODS: Retrospective study of 180 patients undergoing 188 HTx (June 1995-September 2018; 176 first time HTx, 10 second HTx, and 2 third HTx). In 2006, we commenced pre-HTx desensitization for highly sensitized patients and started using tacrolimus as our primary postoperative immunosuppressive agent. The primary outcome was mortality. Survival was modeled by the Kaplan-Meier method. Univariable and multivariable Cox proportional hazard models were created to identify prognostic factors for survival. RESULTS: Our 188 HTx included 18 neonates, 85 infants, 83 children, and 2 adults (>18 years). Median age was 260.0 days (range: 5 days-23.8 years). Median weight was 7.5 kg (range: 2.2-113 kg). Patients in cohort 1 were less likely to have been immunosensitized preoperatively (12.5% vs 28.7%, P = .017). Nevertheless, Kaplan-Meier analysis suggested superior survival in cohort 2 (P = .0045). Patients in cohort 2 were more likely to be alive one year, five years, and ten years after HTx. Multivariable analysis identified the earlier era (hazard ratio [HR] [95% confidence interval] for recent era = 0.32 [0.14-0.73]), transplantation after prior Norwood operation (HR = 4.44 [1.46-13.46]), and number of prior cardiac operations (HR = 1.33 [1.03-1.71]) as risk factors for mortality. CONCLUSIONS: Our analysis of 23 years of pediatric and congenital HTx reveals superior survival in the most recent 12-year era, despite the higher proportion of patients with elevated panel reactive antibody in the most recent era. This improvement was temporally associated with changes in our immunosuppressive strategy.

Closure of a secundum atrial septal defect in two infants with chronic lung disease using the Gore HELEX Septal Occluder.

Children with a secundum atrial septal defect are usually asymptomatic and are referred for elective closure after 3-4 years of age; however, in premature infants with chronic lung disease, bronchopulmonary dysplasia, or pulmonary hypertension, increased pulmonary blood flow secondary to a left-to-right atrial shunt, may exacerbate their condition. Closure of the atrial septal defect in these patients can result in significant clinical improvement. We report the cases of two premature infants with chronic lung disease, who underwent atrial septal defect closure with the Gore HELEX Septal Occluder and discuss the technical aspects of using the device in these patients and their clinical outcomes.

The role of cardiac catheterisation in patients with tetralogy of Fallot.

Cardiac catheterisation plays an important role in the management of patients with tetralogy of Fallot. There are a number of palliative transcatheter interventions that can be performed in the neonatal period to allow for improved oxygen saturations and interval growth of the pulmonary arteries until corrective surgery is performed. Most patients develop branch pulmonary artery stenosis, right ventricular outflow tract obstruction, pulmonary insufficiency, or significant residual left-to-right shunts during long-term follow-up after corrective surgery. Transcatheter interventions can be performed to treat many of these issues, often eliminating or delaying the need for subsequent surgery. The indications for cardiac catheterisation and the specifics for various interventional procedures for patients with tetralogy of Fallot are reviewed in this manuscript.

Blalock-taussig shunt thrombosis prophylaxis in a patient with jacobsen syndrome and thrombocytopenia.

Jacobsen syndrome (JS) is a rare chromosomal anomaly caused by deletions in the distal long arm of chromosome 11. Features of the syndrome include growth and developmental delays, a distinctive facial appearance, and a variety of physical problems including heart defects and bleeding disorders. Congenital heart defects occur in approximately 50% of children with JS. Hypoplastic left heart syndrome (HLHS) has been occasionally reported in association with JS. In such cases, the hematological abnormalities may influence the outcome from single-ventricle palliation through staged surgical reconstruction. Thrombotic obstruction or occlusion of the modified Blalock-Taussig (BT) shunt is a well-documented cause of interstage mortality following the Norwood operation. Although there is no consensus regarding the therapeutic value of antiplatelet therapy during the interstage period following the first stage of palliation, maintenance of shunt patency is critically important. For patients with JS undergoing single-ventricle palliation, decisions regarding antiplatelet therapy during the interstage period may be further complicated by the presence of thrombocytopenia and platelet dysfunction related to JS. We report the case of a patient with HLHS, JS, and thrombocytopenia who underwent the Norwood procedure, and we describe our strategy for prophylaxis against thrombosis of the BT shunt.

Efficient, long-term hepatic gene transfer using clinically relevant HDAd doses by balloon occlusion catheter delivery in nonhuman primates.

Helper-dependent adenoviral vectors (HDAd) are devoid of all viral coding sequences and are thus an improvement over early generation Ad because they can provide long-term transgene expression in vivo without chronic toxicity. However, high vector doses are required to achieve efficient hepatic transduction by systemic intravenous injection, and this unfortunately results in dose-dependent acute toxicity. To overcome this important obstacle, we have developed a minimally invasive method to preferentially deliver HDAd into the liver of nonhuman primates. Briefly, a balloon occlusion catheter was percutaneously positioned in the inferior vena cava to occlude hepatic venous outflow. HDAd was injected directly into the occluded liver via a percutaneously placed hepatic artery catheter. Compared to systemic vector injection, this approach resulted in substantially higher hepatic transduction efficiency using clinically relevant low vector doses and was accompanied by mild-to-moderate acute but transient toxicities. Transgene expression was sustained for up to 964 days. These results suggest that our minimally invasive method of delivery can significantly improve the vector's therapeutic index and may be a first step toward clinical application of HDAd for liver-directed gene therapy.

Pseudo-hydrodynamic delivery of helper-dependent adenoviral vectors into non-human primates for liver-directed gene therapy.

Helper-dependent adenoviral vectors (HDAds) are attractive for liver-directed gene therapy because they can mediate long-term, high-level transgene expression without chronic toxicity. However, systemic delivery requires high vector doses for efficient hepatic transduction, resulting in dose-dependent acute toxicity. Clearly, strategies to improve hepatic transduction with low vector doses are needed. In this regard, we have previously shown that hydrodynamic injection of helper-dependent adenoviral vectors into mice results in increased hepatic transduction, reduced systemic vector dissemination, and reduced pro-inflammatory cytokines compared with conventional injection and thus has the potential to improve dramatically the therapeutic index of helper-dependent adenoviral vectors. Unfortunately, the rapid, large-volume injection used in this method cannot be applied to larger animals. Therefore, we have developed a novel balloon occlusion catheter-based method to mimic hydrodynamic injection of helper-dependent adenoviral vectors into non-human primates that does not require rapid, large-volume injection. Using a low, clinically relevant vector dose, this minimally invasive method results in high-efficiency hepatic transduction with minimal toxicity and stable long-term transgene expression for at least 413 days.

Transcatheter occlusion of a residual muscular ventricular septal defect using an Amplatzer duct occluder in a child with congenitally corrected transposition of the great arteries.

Transcatheter occlusion has become an acceptable alternative to surgery in patients with congenital muscular and residual post-surgical ventricular septal defects (VSD). We present a case of an 11 year old male with congenitally corrected transposition of the great arteries, dextrocardia, pulmonary atresia, VSD, and advanced second degree atrioventricular block who underwent successful transcatheter occlusion of a residual post-surgical VSD with an Amplatzer duct occluder, in preparation for transvenous pacemaker implantation.