How Does Cross-Sectional Imaging Impact the Management of Patients With Single Ventricle After Bidirectional Cavopulmonary Connection?

BACKGROUND: There is currently no consensus regarding the use of surveillance cross-sectional imaging in pediatric patients after bidirectional cavopulmonary connection (BDCPC). We sought to determine how computed tomography with angiography (CTA) and cardiac magnetic resonance (CMR) imaging impacted the clinical management of pediatric patients after BDCPC. METHODS: A single-center retrospective study including patients with single ventricle who had BDCPC between 2010 and 2019, and CTA/CMR studies obtained in these patients, at ≤5 years of age, and with Glenn physiology. Repeat studies on the same patient were included if the clinical situation had changed. The impact of CTA/CMR studies was categorized as major, minor, or none. RESULTS: Twenty-four patients (63% male) and 30 imaging studies (22 CTAs) were included. 60% were obtained in patients with hypoplastic left heart syndrome (HLHS); most common indication was Follow-up after an intervention (23%). 6 CMRs were performed on stable HLHS patients as part of a research protocol, with no clinical concerns. The overall impact of CTA/CMR studies was major in 13 cases (43.3%). CTA/CMR studies performed ≥1 year of age (62.5% vs 21.4%, P = .02) and in non-HLHS patients (66.7% vs 27.8%, P = .035) were associated with major impact. Also, 2/6 Research studies were associated with a major impact. CONCLUSIONS: CTA/CMR imaging in pediatric patients with SV after BDCPC was associated with significant clinical impact in over 40% of cases, with a higher impact if obtained in patients ≥1 year of age and in non-HLHS patients. We cannot disregard the possibility of CMR as a surveillance imaging modality in this population.

A call for innovation in fetal monitoring during fetal surgery.

PURPOSE: A growing number of fetal procedures are performed at specialized fetal care centers for congenital problems that classically would have poor outcomes despite advanced postnatal management. Consistent fetal monitoring is integral to the safety of these challenging and innovative surgeries. However, standardization of fetal monitoring during various forms of fetal surgery has yet to be established. MATERIALS AND METHODS: We searched all articles on literature platforms until August 2019 using the terms "fetal surgery," "fetal monitoring," and "fetal interventions." Titles and abstracts were screened by our coauthors to determine the type of fetal monitoring used in these cases. RESULTS: The search identified 1,625 citations, of which the 50 citations considered most pertinent were included in this review. CONCLUSIONS: Fetal monitoring during in utero fetal surgeries continues to be challenging because of limited physical fetal access and technological aspects. Innovations in fetal cardiac monitoring during fetal surgeries have the potential for continuous and high-fidelity hemodynamic and physiologic monitoring, with the goal of early detection and treatment of fetal compromise.

From Safety to Benefit in Cell Delivery During Surgical Repair of Ebstein Anomaly: Initial Results.

BACKGROUND: The objective of this study is to assess the safety and early impact of intramyocardial delivery of autologous bone marrow-derived mononuclear cells (BM-MNC) at time of surgical Ebstein repair. METHODS: Patients with Ebstein anomaly (ages 6 months to 30 years) scheduled to undergo repair of the tricuspid valve were eligible to participate in this open-label, non-randomized phase I clinical trial. BM-MNC target dose was 1-3 million cells/kg. Ten patients have undergone surgical intervention and cell delivery to the right ventricle (RV) and completed 6-month follow-up. RESULTS: All patients underwent surgical tricuspid valve repair and uneventful BM-MNC delivery; there were no ventricular arrhythmias and no adverse events related to study product or delivery. Echocardiographic RV myocardial performance index improved and RV fractional area change showed an initial decline and then through study follow-up. There was no evidence of delayed myocardial enhancement or regional wall motion abnormalities at injection sites on 6-month follow-up magnetic resonance imaging. CONCLUSIONS: Intramyocardial delivery of BM-MNC after surgical repair in Ebstein anomaly can be performed safely. Echocardiography variables suggest a positive impact of cell delivery on the RV myocardium with improvements in both RV size and wall motion over time. Additional follow-up and comparison to control groups are required to better characterize the impact of cell therapy on the myopathic RV in Ebstein anomaly.

Cone Reconstruction for Ebstein Anomaly: Ventricular Remodeling and Preliminary Impact of Stem Cell Therapy.

OBJECTIVE: To define the impact of tricuspid valve cone reconstruction (CR) on ventricular performance in Ebstein anomaly, both independently and after stem cell therapy. PATIENTS AND METHODS: The control group included 257 patients who had CR between June 2007 and December 2019. Ten subjects of a phase I stem cell therapy trial (May 2017 - March 2019) were compared with the controls to assess the echocardiographic impact on ventricular remodeling. RESULTS: After CR, right ventricular (RV) size decreased and left ventricular (LV) volume increased in all patients. Apical and biplane RV fractional area change (FAC) initially decreased, but rebounded by 6 months postoperation. Short-axis FAC increased early and was maintained at 6 months post-CR in the control group. At 6 months post-CR, cell therapy patients showed a significantly larger increase in short-axis FAC (24.4% vs 29.9%, P=.003). In addition, whereas LV ejection fraction (EF) was unchanged at 6 months post-CR in controls, cell therapy patients showed a significant increase in EF relative to baseline and to controls (55.6% vs 65.0%, P=.007). CONCLUSION: Cone reconstruction reduces tricuspid regurgitation and RV size, but is also associated with increased RV FAC and LV volume. Furthermore, injection of bone marrow-derived stem cells augmented the increase in RV FAC and was associated with improved LV EF at 6 months post-CR. This is evidence of a favorable interventricular interaction. These findings provide motivation for continued investigation into the potential benefits of stem cell therapy in Ebstein anomaly and other congenital cardiac malformations. TRIAL REGISTRATION: clinicaltrials.gov identifier: NCT02914171.

Clinical Impact of Autologous Cell Therapy on Hypoplastic Left Heart Syndrome After Bidirectional Cavopulmonary Anastomosis.

Preservation of right ventricle function (RV) is a key to favorable outcome in Hypoplastic Left Heart Syndrome (HLHS), but methods to preserve or improve RV function are limited. Our goal was to assess the clinical and functional impact of autologous umbilical cord blood-derived mononuclear cells (UCB-MNC) therapy when given to patients with HLHS at Stage II surgery. UCB-MNC patients were enrolled prospectively in a phase I, FDA monitored trial as previously described (Burkhart et al., 2019). Matched retrospective controls were identified by review of clinical databases. Growth and RV echocardiographic variables were assessed in both groups prestage II through the first 6 months postoperatively. Statistical comparisons between the groups at similar postoperative time points were made to define potential impact of the cell therapy. There were 7 UCB-MNC patients and 17 controls. Prestage II, most parameters showed no differences between groups, although median fractional area change (FAC) was slightly greater in the controls (FAC: controls = 45% vs UCB-MNC = 41% P= 0.02). At dismissal, FAC and estimated Ejection Fraction (EF) decreased in controls, while both were unchanged from baseline in UCB-MNC patients (ΔFAC: -5% vs -1%, P < 0.01; ΔEF: -8% vs 0%, P = 0.03, respectively). Subsequently, median FAC increased slightly in UCB-MNC patients over the 6 month follow-up period, while it decreased in controls (ΔFAC: UCB-MNC +3% vs control -5%, P = 0.03). Preoperative weight percentiles were similar in both groups (UCB-MNC 34%ile vs controls 22%ile, P = 0.93). However, by 6 months postoperative, median weight percentile improved to 63% in the UCB-MNC treated group, but declined to 8% in controls (P = 0.02). UCB-MNC therapy appears to limit the initial negative impact on RV FAC and EF seen after stage II surgery. During early follow up, FAC and weight percentile improved in UCB-MNC patients relative to controls, suggesting a beneficial effect of UCB-MNC therapy.

Sequential Minimally Invasive Fetal Interventions for Two Life-Threatening Conditions: A Novel Approach.

INTRODUCTION: In utero interventions are performed in fetuses with "isolated" major congenital anomalies to improve neonatal outcomes and quality of life. Sequential in utero interventions to treat 2 anomalies in 1 fetus have not yet been described. CASE PRESENTATION: Here, we report a fetus with a large left-sided intralobar bronchopulmonary sequestration (BPS) causing mediastinal shift, a small extralobar BPS, and concomitant severe left-sided congenital diaphragmatic hernia (CDH). At 26-week gestation, the BPS was noted to be increasing in size with a significant reduction in right lung volume and progression to fetal hydrops. The fetus underwent ultrasound-guided ablation of the BPS feeding vessel leading to complete tumor regression. However, lung development remained poor (O/E-LHR: 0.22) due to the left-sided CDH, prompting fetal endoscopic tracheal occlusion therapy at 28-week gestation to allow increased lung growth. After vaginal delivery, the newborn underwent diaphragmatic repair with resection of the extralobar sequestration. He was discharged home with tracheostomy on room air at 9 months. DISCUSSION/CONCLUSION: Sequential in utero interventions to treat 2 severe major anomalies in the same fetus have not been previously described. This approach may be a useful alternative in select cases with otherwise high morbidity/mortality. Further studies are required to confirm our hypothesis.

Fetal Surgery in the Era of SARS-CoV-2 Pandemic: A Single-Institution Review.

OBJECTIVE: To cope with the changing health care services in the era of SARS-CoV-2 pandemic. We share the institutional framework for the management of anomalous fetuses requiring fetal intervention at Mayo Clinic, Rochester, Minnesota. To assess the success of our program during this time, we compare intraoperative outcomes of fetal interventions performed during the pandemic with the previous year. PATIENTS: We implemented our testing protocol on patients undergoing fetal intervention at our institution between March 1, and May 15, 2020, and we compared it with same period a year before. A total of 17 pregnant patients with anomalous fetuses who met criteria for fetal intervention were included: 8 from 2019 and 9 from 2020. METHODS: Our testing protocol was designed based on our institutional perinatal guidelines, surgical requirements from the infection prevention and control (IPAC) committee, and input from our fetal surgery team, with focus on urgency of procedure and maternal SARS-CoV-2 screening status. We compared the indications, types of procedures, maternal age, gestational age at procedure, type of anesthesia used, and duration of procedure for cases performed at our institution between March 1, 2020, and May 15, 2020, and for the same period in 2019. RESULTS: There were no statistically significant differences among the number of cases, indications, types of procedures, maternal age, gestational age, types of anesthesia, and duration of procedures (P values were all >.05) between the pre-SARS-CoV-2 pandemic in 2019 and the SARS-CoV-2 pandemic in 2020. CONCLUSIONS: Adoption of new institutional protocols during SARS-CoV-2 pandemic, with appropriate screening and case selection, allows provision of necessary fetal intervention with maximal benefit to mother, fetus, and health care provider.

In Utero Restoration of Hindbrain Herniation in Fetal Myelomeningocele as Part of Prenatal Regenerative Therapy Program at Mayo Clinic.

OBJECTIVE: To assess our initial experience with prenatal restoration of hindbrain herniation following in utero repair of myelomeningocele (MMC). PATIENTS AND METHODS: Three consecutive patients with prenatally diagnosed MMC (between January 1, 2018 and September 30, 2018) were managed with open in utero surgery. As per institutional review board approval and following a protocol designed at the Mayo Clinic Maternal & Fetal Center, fetal intervention was offered between 19 0/7 and 25 6/7 weeks of gestation. Prenatal improvement of hindbrain herniation was the declared restorative end point. Obstetrical and perinatal outcomes were also assessed. RESULTS: Diagnosis of MMC was confirmed upon referral between 20 and 21 weeks' gestation by using fetal ultrasound and magnetic resonance imaging. In all cases reported here, the spinal defect was lumbosacral with evidence of hindbrain herniation. Open in utero MMC repair was performed between 24 and 25 weeks' gestation with no notable perioperative complications. Postprocedure fetal magnetic resonance imaging performed 6 weeks after in utero repair documented improvement of hindbrain herniation. Deliveries were at 37 weeks by cesarean section without complications. Most recent postnatal follow-ups were unremarkable at both 11 months (baby 1) and 3 months of age (baby 2), with mild ventriculomegaly. Antenatal and postnatal follow-up of baby 3 at 1 month of age was also unremarkable. CONCLUSION: Our study highlights the prenatal restoration of hindbrain herniation following in utero MMC repair in all cases presented here as an example of a prenatal regenerative therapy program in our institution.

Magnetic Resonance Elastography: A Novel Technique for the Detection of Hepatic Fibrosis and Hepatocellular Carcinoma After the Fontan Operation.

OBJECTIVE: To evaluate the utility of magnetic resonance elastography (MRE) in screening patients for hepatic fibrosis, cirrhosis, and hepatocellular carcinoma after the Fontan operation. PATIENTS AND METHODS: Hepatic MRE was performed in conjunction with cardiac magnetic resonance imaging in patients who had undergone a Fontan operation between 2010 and 2014. Liver stiffness was calculated using previously reported techniques. Comparisons to available clinical, laboratory, imaging, and histopathologic data were made. RESULTS: Overall, 50 patients at a median age of 25 years (range, 21-33 years) who had undergone a Fontan operation were evaluated. The median interval between Fontan operation and MRE was 22 years (range, 16-26 years). The mean liver stiffness values were increased: 5.5 ± 1.4 kPa relative to normal participants. Liver stiffness directly correlated with liver biopsy-derived total fibrosis score, time since operation, mean Fontan pressure, γ-glutamyltransferase level, Model for End-Stage Liver Disease score, creatinine level, and pulmonary vascular resistance index. Liver stiffness was inversely correlated with cardiac index. All 3 participants with hepatic nodules exhibiting decreased contrast uptake on delayed postcontrast imaging and increased nodule stiffness had biopsy-proven hepatocellular carcinoma. CONCLUSION: The association between hepatic stiffness and fibrosis scores, Model for End-Stage Liver Disease scores, and γ-glutamyltransferase level suggests that MRE may be useful in detecting (and possibly quantifying) hepatic cirrhosis in patients after the Fontan operation. The correlation between stiffness and post-Fontan time interval, mean Fontan pressure, pulmonary vascular resistance index, and reduced cardiac index suggests a role for long-term hepatic congestion in creating these hepatic abnormalities. Magnetic resonance elastography was useful in detecting abnormal nodules ultimately diagnosed as hepatocellular carcinoma. The relationship between stiffness with advanced fibrosis and hepatocellular carcinoma provides a strong argument for additional study and broader application of MRE in these patients.