Stage 1 and 2 Palliation: Comparing Ductal Stenting and Aorto-Pulmonary Shunts in Single Ventricles with Duct-Dependent Pulmonary Blood Flow.

Patent ductus arteriosus stenting (PDAS) for ductal-dependent pulmonary blood flow (DDPBF) provides a new paradigm for managing neonates with single ventricles (SV). Currently, sparse data exist regarding outcomes for subsequent palliation. We describe our experience with inter-stage care and stage 2 (S2P) conversion with PDAS in comparison to a prior era of patients who received surgical aorto-pulmonary shunts (APS). Retrospective review of 18 consecutive DDPBF SV patients treated with PDAS between 2016 and 2021 was done and compared with 9 who underwent APS from 2010 to 2016. Patient outcomes and pulmonary artery (PA) growth were analyzed. S2P was completed in all 18 with PDAS with no cardiac arrests and one post-S2P mortality. In the 9 APS patients, there was one cardiac arrest requiring ECMO and one mortality inter-stage. Off cardiopulmonary bypass strategy was utilized in 10/18 in the PDAS and 1/9 in the APS group (p = 0.005) at S2P. Shorter ventilation time, earlier PO feeding, and shorter hospital stay were noted in the PDAS group (p = 0.01, p = 0.006, p = 0.03) (S2P). Median Nakata index increase inter-stage was not significant between the PDAS and APS at 94.1 mm2/m2 versus 71.7 mm2/m2 (p = 0.94). Median change in pulmonary artery symmetry (PAS) was - 0.02 and - 0.24, respectively, which was statistically significant (p = 0.008). Neurodevelopmental outcomes were better in the PDAS group compared to the APS group (p = 0.02). PDAS provides excellent PA growth, inter-stage survival, progression along multistage single-ventricle palliation, and potentially improved neurodevelopmental outcomes. Most patients can be transitioned through 2 stages of palliation without CPB.

Right Atrial Lines as Primary Access for Postoperative Pediatric Cardiac Patients.

To characterize the use of right atrial lines (RALs) as primary access in the postoperative care of neonatal and pediatric patients after cardiothoracic surgery and to identify risk factors associated with RAL complications. Observational retrospective cohort study in pediatric cardiac patients who underwent RAL placement in a tertiary children's hospital from January 2011 through June 2018. A total of 692 children with congenital heart disease underwent 815 RAL placements during the same or subsequent cardiothoracic surgeries during the study period. Median age and weight were 22 days (IQR 7-134) and 3.6 kg (IQR 3.1-5.3), respectively. Neonates accounted for 53.5% of patients and those with single-ventricle physiology were 35.4%. Palliation surgery (shunts, cavo-pulmonary connections, hybrid procedures, and pulmonary artery bandings) accounted for 38%. Survival to hospital discharge was 95.5%. Median RAL duration was 11 days (IQR 7-19) with a median RAL removal to hospital discharge time of 0 days (IQR 0-3). Thrombosis and migration were the most prevalent complications (1.7% each), followed by malfunction (1.4%) and infection (0.7%). Adverse events associated with complications were seen in 12 (1.4%) of these RAL placements: decrease in hemoglobin (n = 1), tamponade requiring pericardiocentesis (n = 3), pleural effusion requiring chest tube (n = 2), and need for antimicrobials (n = 6). Multivariable logistic regression showed that RAL duration (OR 1.01, p = 0.006) and palliation surgery (OR 2.38, p = 0.015) were significant and independent factors for complications. The use of RALs as primary access in postoperative pediatric cardiac patients seems to be feasible and safe. Our overall incidence of complications from prolonged use of RALs remained similar or lower to that reported with short-term use of these lines. While RAL duration and palliation surgeries seemed to be associated with complications, severity of illness could be a confounding factor. A prospective assessment of RAL complications may improve outcomes in this medically complex population.

Organ transplantation using COVID-19-positive deceased donors.

The COVID-19 pandemic has influenced organ transplantation decision making. Opinions regarding the utilization of coronavirus disease-2019 (COVID-19) donors are mixed. We hypothesize that COVID-19 infection of deceased solid organ transplant donors does not affect recipient survival. All deceased solid organ transplant donors with COVID-19 testing results from March 15, 2020 to September 30, 2021 were identified in the OPTN database. Donors were matched to recipients and stratified by the COVID-19 test result. Outcomes were assessed between groups. COVID-19 test results were available for 17 694 donors; 150 were positive. A total of 269 organs were transplanted from these donors, including 187 kidneys, 57 livers, 18 hearts, 5 kidney-pancreases, and 2 lungs. The median time from COVID-19 testing to organ recovery was 4 days for positive and 3 days for negative donors. Of these, there were 8 graft failures (3.0%) and 5 deaths (1.9%). Survival of patients receiving grafts from COVID-19-positive donors is equivalent to those receiving grafts from COVID-19-negative donors (30-day patient survival = 99.2% COVID-19 positive; 98.6% COVID-19 negative). Solid organ transplantation using deceased donors with positive COVID-19 results does not negatively affect early patient survival, though little information regarding donor COVID-19 organ involvement is known. While transplantation is feasible, more information regarding COVID-19-positive donor selection is needed.

Selective Valve Removal for Melody Valve Endocarditis: Practice Variations in a Multicenter Experience.

Guidelines for management of Melody transcatheter pulmonary valve (TPV) infective endocarditis (IE) are lacking. We aimed to identify factors associated with surgical valve removal versus antimicrobial therapy in Melody TPV IE. Multicenter retrospective analysis of all patients receiving Melody TPV from 10/2010 to 3/2019 was performed to identify cases of IE. Surgical explants versus non-surgical cases were compared. Of the 663 Melody TPV implants, there were 66 cases of IE in 59 patients (59/663, 8.8%). 39/66 (59%) were treated with IV antimicrobials and 27/66(41%) underwent valve explantation. 26/59 patients (44%) were treated medically without explantation or recurrence with average follow-up time of 3.5 years (range:1-9). 32% of Streptococcus cases, 53% of MSSA, and all MRSA cases were explanted. 2 of the 4 deaths had MSSA. CART analysis demonstrated two important parameters associated with explantation: a peak echo gradient ≥ 47 mmHg at IE diagnosis(OR 10.6, p < 0.001) and a peak echo gradient increase of > 24 mmHg compared to baseline (OR 6.7, p = 0.01). Rates of explantation varied by institution (27 to 64%). In our multicenter experience, 44% of patients with Melody IE were successfully medically treated without valve explantation or recurrence. The degree of valve stenosis at time of IE diagnosis was strongly associated with explantation. Rates of explantation varied significantly among the institutions.

Pulmonary Artery Banding for Children With Dilated Cardiomyopathy: US Experience.

Pulmonary artery band placement is a recently described therapeutic strategy for dilated cardiomyopathy with preserved right ventricular function, originally reported from Germany.1 We present the results of the multicenter retrospective study of pulmonary artery band experience in the United States, with comparison to the German experience. Five centers contributed a total 14 patients (median age 5 months, interquartile range 3.5-10). Mechanical ventilation was required in 9/12 (75%) patients and inotropes were used in 13/14 (93%) patients preoperatively. Ultimately, 4 (29%) patients experienced cardiac recovery, 8 (57%) were bridged to cardiac transplantation (6 with ventricular assist device placement), and 2 (14%) died. Although both the US and Germany series demonstrated high prevalence of achieving patients' individual target (either cardiac recovery or transplant), the mode of success was different (recovery rate: <1/3 in the United States and >2/3 in Germany). Lower recovery rate may be a reflection of sicker preoperative status, and thereby a more advanced stage of heart failure (preoperative intubation: >2/3 in the United States vs <1/3 in Germany). Further studies would be warranted to gain more insight into patient selection as well as optimal timing for the intervention.

Dead space fractions in neonates following first-stage palliation for hypoplastic left heart syndrome.

PURPOSE: (1) To characterise changes in dead space fraction during the first 120 post-operative hours in neonates undergoing stage 1 palliation for hypoplastic left heart syndrome, including hybrid procedure; (2) to document whether dead space fraction varied by shunt type (Blalock-Taussig shunt and Sano) and hybrid procedure; and (3) to determine the association between dead space fraction and outcomes. METHODS: Retrospective chart review in neonates undergoing stage 1 palliation for hypoplastic left heart syndrome in a cardiac intensive care unit over a consecutive 30-month period. A linear mixed model was used to determine the differences in dead space over time. Multivariable linear regression and a multivariable linear mixed model were used to assess the association between dead space and outcomes at different time points and over time, respectively. RESULTS: Thirty-four neonates received either a Blalock-Taussig shunt (20.5%), Sano shunt (59%), or hybrid procedure (20.5%). Hospital mortality was 8.8%. Dead space fractions in patients undergoing the hybrid procedure were significantly lower on day 1 (p = 0.01) and day 2 (p = 0.02) and increased over time. A dead space fraction >0.6 on post-operative days 3-5 was significantly associated with decreased duration of mechanical ventilation in all surgical groups (p 0.6 on post-operative days 3-5 was associated with lower duration of mechanical ventilation in all surgical groups. A more comprehensive, prospective assessment of dead space in this delicate patient population would likely be beneficial in improving outcomes.

Alternative methods for virtual heart transplant-Size matching for pediatric heart transplantation with and without donor medical images available.

BACKGROUND: Listed pediatric heart transplant patients have the highest solid-organ waitlist mortality rate. The donor-recipient body weight (DRBW) ratio is the clinical standard for allograft size matching but may unnecessarily limit a patient's donor pool. To overcome DRBW ratio limitations, two methods of performing virtual heart transplant fit assessments were developed that account for patient-specific nuances. Method 1 uses an allograft total cardiac volume (TCV) prediction model informed by patient data wherein a matched allograft 3-D reconstruction is selected from a virtual library for assessment. Method 2 uses donor images for a direct virtual transplant assessment. METHODS: Assessments were performed in medical image reconstruction software. The allograft model was developed using allometric/isometric scaling assumptions and cross-validation. RESULTS: The final predictive model included gender, height, and weight. The 25th-, 50th-, and 75th-percentiles for TCV percentage errors were -13% (over-prediction), -1%, and 8% (under-prediction), respectively. Two examples illustrating the potential of virtual assessments are presented. CONCLUSION: Transplant centers can apply these methods to perform their virtual assessments using existing technology. These techniques have potential to improve organ allocation. With additional experience and refinement, virtual transplants may become standard of care for determining suitability of donor organ size for an identified recipient.

Pulmonary Dead Space Fraction and Extubation Success in Children After Cardiac Surgery.

OBJECTIVES: 1) Determine the correlation between pulmonary dead space fraction and extubation success in postoperative pediatric cardiac patients; and 2) document the natural history of pulmonary dead space fractions, dynamic compliance, and airway resistance during the first 72 hours postoperatively in postoperative pediatric cardiac patients. DESIGN: A retrospective chart review. SETTING: Cardiac ICU in a quaternary care free-standing children's hospital. PATIENTS: Twenty-nine with balanced single ventricle physiology, 61 with two ventricle physiology. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We collected data for all pediatric patients undergoing congenital cardiac surgery over a 14-month period during the first 72 hours postoperatively as well as prior to extubation. Overall, patients with successful extubations had lower preextubation dead space fractions and shorter lengths of stay. Single ventricle patients had higher initial postoperative and preextubation dead space fractions. Two-ventricle physiology patients had higher extubation failure rates if the preextubation dead space fraction was greater than 0.5, whereas single ventricle patients had similar extubation failure rates whether preextubation dead space fractions were less than or equal to 0.5 or greater than 0.5. Additionally, increasing initial dead space fraction values predicted prolonged mechanical ventilation times. Airway resistance and dynamic compliance were similar between those with successful extubations and those who failed. CONCLUSIONS: Initial postoperative dead space fraction correlates with the length of mechanical ventilation in two ventricle patients but not in single ventricle patients. Lower preextubation dead space fractions are a strong predictor of successful extubation in two ventricle patients after cardiac surgery, but may not be as useful in single ventricle patients.

Myocardial Infarction in a Seven-Year-Old Girl With Left Atrial Myxoma.

Left atrial (LA) myxomas are benign neoplasms that are rare in children. Their presentation is dependent on size and location. We describe a seven-year-old girl who was admitted with chest pain, upper respiratory symptoms, and persistent troponin elevation with suspected myocarditis. Workup revealed an infarction from a LA myxoma which embolized to her right coronary artery-posterior lateral branch (PLB). She underwent prompt successful surgical excision of the myxoma. We elected not to perform a coronary artery embolectomy and her infarction was managed medically. We describe this unique clinical scenario and the decision-making process leading to a successful outcome.

The role of extracorporeal life support in acute myocarditis: a bridge to recovery?

Acute myocardial failure associated with myocarditis is highly lethal. Left ventricular assist device support for these patients has been advocated to decompress the left ventricle and facilitate myocardial remodeling and recovery. Concerns exist regarding the ability of venoarterial (VA) extracorporeal life support (ECLS) to decompress the left ventricle and allow effective myocardial recovery. ECLS has several advantages, including availability, rapid deployment, and flexibility, as compared with contemporary ventricular assist devices. The objective of this study was to provide a brief review of acute myocarditis and present our series of patients. After Institutional Review Board approval, we conducted a retrospective data analysis of patients on ECLS experiencing rapidly progressive myocardial failure from a normal baseline. Patients with a history of intrinsic heart disease were excluded. All patients were thought to have myocarditis and had failed medical therapy requiring emergent ECLS support. Five patients demographics are detailed in Table 1. Patients experienced life-threatening intractable dysrhythmias or cardiac arrest and were refractory to medical therapy with severe acidosis and impending multisystem organ failure. All patients were stabilized with VA ECLS, and the left ventricle and atrium were decompressed in four of five patients. A left atrial vent was placed in one patient. Myocardial recovery with successful weaning from ECLS was obtained in four of five patients and to a normal ejection fraction in three of the five. One patient failed ECLS weaning and required biventricular VAD support secondary to severe myocardial necrosis from giant cell myocarditis and was transplanted, one died, all others are alive at follow-up. ECLS is safe and effective to treat acute myocardial failure and may be used to obtain myocardial recovery in certain subsets. We devised a decision algorithm for ECLS deployment in this patient cohort and routinely use ECLS.

Repair of Anomalous Single Coronary Artery From the Pulmonary Artery (ASCAPA).

We describe the management of an infant presenting with severe heart failure at 6 weeks of age found to have an anomalous single coronary artery originating from the main pulmonary artery (MPA). This patient was transferred to our hospital and ultimately had their coronary artery translocated to the ascending aorta successfully. Preoperative severe left ventricular (LV) dysfunction and moderate/severe mitral regurgitation (MR) improved to normal function and mild-to-moderate MR 6 weeks postrepair. Three-dimensional CT reconstructions proved valuable and allowed for accurate preoperative planning leading to successful coronary transfer.

Purpose-Built Transcatheter Cavopulmonary Anastomosis Device Requirements: Multi-Modality Imaging Evaluation.

BACKGROUND/PURPOSE: Patients with a functional single ventricle undergo multiple, palliative open-heart surgeries. This includes a superior cavopulmonary anastomosis or bidirectional Glenn shunt. A less-invasive transcatheter approach may reduce morbidity. METHODS/MATERIALS: We analyzed pre-Glenn X-ray contrast angiography (XA), cardiac computed tomography (CT), and cardiac magnetic resonance (CMR) studies. RESULTS: Over an eleven-year period (1/2007 - 6/2017), 139 Glenn surgeries were performed at our institution. The typical age range at surgery was 59 - 371 days (median = 163; IQR = 138 - 203). Eight-nine XA, ten CT, and ten CMR studies obtained from these patients were analyzed. Cephalad SVC measurements (millimeters) were 7.3 ± 1.7 (XA), 7.7 ± 1.6 (CT) and 6.9 ± 1.8 (CMR). RPA measurements were 7.3 ± 1.9 (XA), 7.4 ± 1.6 (CT) and 6.6 ± 1.9 (CMR). Potential device lengths were 10.9 ± 6 - 17.4 ± 6.4 (XA), 10.1 ± 2.1 - 17.7 ± 2.4 (CT) and 17.3 ± 4. - 23.7 ± 5.5 (CMR). SVC-RPA angle (degrees) was 132.9 ± 13.2 (CT) and 140 ± 10.2 (MRI). Image quality of all CT (100%), almost all XA (SVC 100%, RPA 99%), and most MRI (SVC 80%, RPA 90%) were deemed sufficient. Parametric modeling virtual fit device with 10 mm diameter and 20 - 25 mm length was ideal. CONCLUSIONS: Ideal transcatheter cavopulmonary shunt device for the typical patient would be 10 mm in diameter and 20-25 mm in length.

Staged Repair of Van Praagh Truncus Type A3.

Van Praagh (VP) A3 variant of truncus arteriosus (or common arterial trunk) is defined by only one pulmonary artery (usually the right) originating from the common trunk, while the other lung is supplied either by collaterals or a pulmonary artery arising from the aortic arch. This report describes a staged approach to manage a VP-A3 variant truncus arteriosus with ductal origin of the left pulmonary artery (LPA), a hypoplastic right pulmonary artery, and cyanosis. Initially, the ductal portion of the proximal LPA was stented with a Resolute Onyx drug-eluting stent. The pulmonary arteries grew and at four months of age had an acceptable McGoon ratio and Nakata index. The patient then underwent repair which included unifocalization of the branch pulmonary arteries, closure of the ventricular septal defect, and placement of a right ventricle-to-pulmonary artery homograft conduit.

Bronchial stenting in infants with severe bronchomalacia: Technique and outcomes.

OBJECTIVES: To report the first use of a balloon expandable bare metal stent for treating infant bronchomalacia. BACKGROUND: Infant bronchomalacia often requires prolonged mechanical ventilation and can be life-threatening. Effective treatment for severe infant bronchomalacia continues to be elusive. We present three cases of bronchial stenting for no-option or treatment refractory infant bronchomalacia. METHODS: Three consecutive cases of stenting to relieve conservative treatment refractory severe infant bronchomalacia were performed between February 2019 and December 2020. Initial diagnosis was confirmed with Computed Tomography (CT) angiography. Patients underwent rigid micro laryngoscopy, bronchoscopy, and flexible bronchoscopy to evaluate the airway. Initial conservative management strategies were pursued. Patients failing initial conservative management strategies were considered for rescue bronchial stenting. RESULTS: Our initial clinical experience with a coronary bare metal stent for these procedures has been favorable. The stent was easy to deploy with precision. We did not encounter stent embolization or migration. There was sufficient stent radial strength to relieve bronchomalacia without causing restenosis or erosion. There was no significant granulation tissue formation. In one patient, the stent was removed after 12 months of somatic growth; this was uneventful and bronchial patency was maintained. There were no complications in any of our patients regarding stent placement and reliability. CONCLUSION: In cases of three infants with severe bronchomalacia, we found that bronchial stenting with the bare metal coronary stent was effective in relieving bronchial stenosis.

Heart Transplantation of a Preterm Infant With HLHS.

A 33-week gestation, 1.75-kg female infant with mitral stenosis/aortic atresia variant of hypoplastic left heart syndrome and severe ventriculo-coronary connections underwent surgical septectomy and bilateral pulmonary artery banding at five weeks of age (2.10 kg). After separation from bypass, she developed hemodynamic instability requiring venoarterial extracorporeal membrane oxygenation support. She was listed for heart transplantation and transplanted after three days of support with an oversized heart (4.7:1 donor-recipient weight ratio).

An Anterior Anastomosis for the Modified Fontan Connection: A Hemodynamic Analysis.

This hemodynamic feasibility study examined total cavopulmonary connection (TCPC) designs connecting the extracardiac conduit to the anterior surface of pulmonary arteries (PAs) or superior vena cava (SVC) rather than to the inferior PA surface (traditional TCPC). The study involved twenty-five consecutive Fontan patients meeting inclusion criteria from a single institution. A virtual surgical platform mimicked the completed traditional TCPC and generated three anterior anastomosis designs: Anterior-PA, Middle-SVC, and SVC-Inn (Inn: innominate vein). Hemodynamic performance of anterior anastomosis designs was compared with the traditional TCPC regarding indexed power loss (iPL) and hepatic flow distribution (HFD). Compared to the traditional TCPC, the Anterior-PA design produces a similar iPL. The Middle-SVC design is also similar, though the iPL difference is positively correlated with the anastomosing height. The SVC-Inn design had significantly more iPL. The three anterior anastomosis designs did not have a significant difference in HFD (from traditional TCPC). Pulmonary flow distribution (PFD) has a stronger correlation with HFD from the anterior anastomosis designs than the traditional TCPC. This hemodynamic feasibility study examined anterior anastomosis, extracardiac TCPC designs that may offer surgeons clinical dexterity. The Anterior-PA design may be equivalent to the traditional TCPC. Fontan extracardiac conduit anastomosis just superior to the PAs (Middle-SVC) also preserves hemodynamic performance and avoids direct PA anastomosis. These designs could simplify surgical Fontan completion, and may particularly benefit patients requiring surgical dissection, having atypical PA orientation, or after PA stent angioplasty.

Patent Ductus Arteriosus Stenting for All Ductal-Dependent Cyanotic Infants: Waning Use of Blalock-Taussig Shunts.

[Figure: see text].

Rapid whole genome sequencing impacts care and resource utilization in infants with congenital heart disease.

Congenital heart disease (CHD) is the most common congenital anomaly and a major cause of infant morbidity and mortality. While morbidity and mortality are highest in infants with underlying genetic conditions, molecular diagnoses are ascertained in only ~20% of cases using widely adopted genetic tests. Furthermore, cost of care for children and adults with CHD has increased dramatically. Rapid whole genome sequencing (rWGS) of newborns in intensive care units with suspected genetic diseases has been associated with increased rate of diagnosis and a net reduction in cost of care. In this study, we explored whether the clinical utility of rWGS extends to critically ill infants with structural CHD through a retrospective review of rWGS study data obtained from inpatient infants < 1 year with structural CHD at a regional children's hospital. rWGS diagnosed genetic disease in 46% of the enrolled infants. Moreover, genetic disease was identified five times more frequently with rWGS than microarray ± gene panel testing in 21 of these infants (rWGS diagnosed 43% versus 10% with microarray ± gene panels, p = 0.02). Molecular diagnoses ranged from syndromes affecting multiple organ systems to disorders limited to the cardiovascular system. The average daily hospital spending was lower in the time period post blood collection for rWGS compared to prior (p = 0.003) and further decreased after rWGS results (p = 0.000). The cost was not prohibitive to rWGS implementation in the care of this cohort of infants. rWGS provided timely actionable information that impacted care and there was evidence of decreased hospital spending around rWGS implementation.

Aortic Root Thrombosis on ECMO-A Novel Management Strategy.

A 15-year-old presented in cardiogenic shock secondary to viral myocarditis requiring venoarterial extracorporeal membrane oxygenation (ECMO) support. He developed large thrombi of the left ventricle and aortic root. Anticoagulation was increased, and medications were initiated to decrease the likelihood of aortic valve opening. He underwent balloon atrial septostomy followed by placement of a left atrial vent. A pigtail catheter was placed in the ascending aorta for direct heparin infusion. Serial echocardiograms showed progressive resolution of the thrombi. He was successfully weaned from ECMO and discharged home without neurological deficits.

Prolonged use of dexmedetomidine in the paediatric cardiothoracic intensive care unit.

BACKGROUND: Dexmedetomidine is an alpha2-adrenergic agonist that causes sleep-like sedation and mild analgesia without narcosis or respiratory depression, and has relative cardiovascular stability. Due to these properties, it may be an effective agent for prolonged use in the sedation of patients in the paediatric cardiothoracic intensive care unit. We reviewed our experience with the drug to detail its safety and efficacy. METHODS: We conducted a retrospective chart review of all patients who received dexmedetomidine over a six month period in a dedicated paediatric cardiothoracic intensive care unit. Patients were identified from pharmacy records showing administration of drugs. We collected demographic data, information relating to doses of dexmedetomidine, physiologic parameters, and clinical outcomes. RESULTS: We identified 54 patients who received the drug. The median age of recipients was 6 months, with a range from 1 day to 16 years. The mean duration of administration was 37.3 hours, with a range from 2 to 177 hours. The mean duration of continuation of administration after extubation was 16.7 hours, with a range from zero to 112.5 hours. Physiologically, there were no clinically significant changes in mean arterial pressure, heart rate, respiratory rate, or saturations of oxygen before, during, or after utilization of the drug. Use of dexmedetomidine significantly reduced the need to administer narcotics, and scores using the COMFORT system were not different between patients who received dexmedetomidine and those who did not. CONCLUSIONS: In this limited and retrospective review, dexmedetomidine was found to be safe and efficacious. Its use as a sedative agent for extended periods of time in critically-ill children deserves investigation in a prospective and controlled manner.