Retrograde Pulmonary Valve Perforation and Stenting through a Major Aorto-Pulmonary Collateral Artery.

Management of pulmonary atresia, ventricular septal defect with major aorto-pulmonary collateral arteries, and hypoplastic native pulmonary arteries focuses on growth of the native pulmonary arteries. One strategy to grow the native pulmonary arteries is through pulmonary valve perforation followed by right ventricular outflow tract stenting, if suitable. We present a unique case of retrograde pulmonary valve perforation and stenting of the right ventricular outflow tract through a major aorto-pulmonary collateral artery.

Use of mechanical thrombectomy in very early-onset inflammatory bowel disease patient with extensive venous thrombosis.

Mechanical thrombectomy is generally used in adult patients with pulmonary embolism or extensive venous thromboembolism, but it is starting to become more prevalent in the children. We present a unique case of a 3-year-old female with very early-onset inflammatory bowel disease with extensive venous thromboembolism who underwent successful mechanical thrombectomy.

Evaluation of conventional troponin I testing for the detection of myocardial dysfunction in children.

Objectives: Troponin is a marker of myocardial injury but is not well studied in children. Our primary objective was to ascertain the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of conventional troponin I for the detection of acute myocardial dysfunction in previously healthy children. Our secondary objective was to identify clinical predictors of myocardial dysfunction in the setting of elevated troponin. Study Design: This was a retrospective chart review in a single, paediatric, tertiary care centre of troponin tests performed in all admitted children over a 4-year period. Demographics, symptoms, signs, chest x-ray, ECG, and echocardiogram abnormalities were documented. Myocardial dysfunction was presumed to be absent when the patient had a normal cardiac assessment, with or without echocardiography, and did not re-present. Results: From January 2014 through December 2017, 566 patients had troponin tested as a screen for myocardial injury. Troponin was positive in 38 of 566 cases (6.7%). Myocardial dysfunction was detected in 9 of 566 cases (1.6%). Troponin was elevated in six of nine cases of myocardial dysfunction. The sensitivity of conventional troponin I for detecting acute myocardial dysfunction was 66% (95% confidence interval [CI] 30 to 93%). The specificity was 94% (95% CI 92 to 96%). PPV was 16% (95% CI 6 to 31%) and NPV 99% (95% CI 98 to 100%). An abnormal ECG was more prevalent in patients with a true positive versus a false-positive troponin result (P=0.03). Conclusion: Troponin testing identified few cases of myocardial dysfunction. We found the test to have only 66% sensitivity. Troponin testing as a screen for myocardial injury in children has limited utility.

Initial experience with vascular plug devices for mechanical thrombectomy in symptomatic neonates and infants.

OBJECTIVES: To describe a novel technique for mechanical thrombectomy (MT) in young children. BACKGROUND: Acute thrombosis in children may be a cause of significant morbidity or mortality. MT options in children are limited due to patient and vessel size, prompting consideration of innovative approaches. METHODS: Two-center review of children with symptomatic non-cerebral thrombotic vessel occlusion. A novel approach to MT was performed using a deployed but unreleased amplatzer vascular plug (AVP) to "scrape" the target vessel in retrograde fashion, thereby harvesting the thrombus via the access sheath. RESULTS: AVP-MT was performed in four patients at a median age of 2 months (range: 1 day-11 months) and median weight of 5.6 kg (1.8-10.9). In two cases, AVP-MT was performed in isolation in neonates on cervical extracorporeal membrane oxygenation (ECMO) support with cannula-associated obstructive aortic and brachiocephalic thrombus. AVP-MT was also performed as adjunctive therapy in a patient with single ventricle physiology and pulmonary artery thrombosis and in an infant with mitral valve endocarditis and femoral arterial thromboembolism. In all cases, AVP-MT was used to successfully remove thrombus from the target vessel and restore arterial flow, without procedural complications. Recurrent thrombosis occurred in both neonates, due to persistence of the ECMO cannula, with subsequent mortality. The other children were free of recurrent thrombus at 2 and 34 months. CONCLUSIONS: Acute relief of symptomatic thrombosis may be achieved using AVP-MT in small children, although thrombosis frequently recurs, and clinical prognosis may remain poor. This strategy should be considered when alternative MT treatment options are not applicable.

Pulmonary artery wall thickness in children with Fontan physiology: an optical coherence tomography case control study.

INTRODUCTION: Failure of the Fontan circulation is not a well-understood clinical phenomena.For some patients, a gradual increase in pulmonary vascular resistance (PVR) and structural changes in the pulmonary artery may be an important causative factor. To further investigate this issue, we employed optical coherence tomography (OCT) to evaluate structural changes within the pulmonary arteries of Fontan patients and compared to those with a normal pulmonary circulation. MATERIALS AND METHODS: Pulmonary artery OCT was performed, without complications, in 12 Fontan and 11 control patients. Wall thickness and wall:vessel cross-sectional area (CSA) ratio were calculated after image acquisition, using digital planimetry. RESULTS: There was no difference in wall thickness between both groups. Median wall thickness for Fontan patients was 0.12 mm (IQR, 0.10-0.14) and for controls was 0.11 mm (IQR, 0.10-0.12; p = 0.62). Wall:vessel CSA ratio for Fontan patients was 0.13 (IQR, 0.12-0.16) and for controls was 0.13 (IQR, 0.11-0.15) (p = 0.73). There was no association between wall thickness and ventricle morphology, age at catheterisation, age at Fontan, years since Fontan completion, pulmonary artery pressure, and PVR. The vessel media was more readily visualised in control patients. DISCUSSION: OCT of the pulmonary arteries in Fontan patients is safe and feasible. Our OCT findings suggest that during childhood, pulmonary artery wall dimensions are normal in Fontan children with reassuring hemodynamics. Further evaluation of Fontan patients with abnormal hemodynamics and serial evaluation into adulthood are required to conclude on the utility of OCT for identifying early pulmonary artery structural changes.

Clinical application of three-dimensional printing to the management of complex univentricular hearts with abnormal systemic or pulmonary venous drainage.

In recent years, three-dimensional printing has demonstrated reliable reproducibility of several organs including hearts with complex congenital cardiac anomalies. This represents the next step in advanced image processing and can be used to plan surgical repair. In this study, we describe three children with complex univentricular hearts and abnormal systemic or pulmonary venous drainage, in whom three-dimensional printed models based on CT data assisted with preoperative planning. For two children, after group discussion and examination of the models, a decision was made not to proceed with surgery. We extend the current clinical experience with three-dimensional printed modelling and discuss the benefits of such models in the setting of managing complex surgical problems in children with univentricular circulation and abnormal systemic or pulmonary venous drainage.

An infant with out-of-hospital cardiac arrest secondary to enteroviral myocarditis surviving up to cardiac transplantation.

We report the case of a 13-day-old infant with enteroviral myocarditis surviving an out-of-hospital cardiac arrest. She underwent orthotopic cardiac transplantation three months later. A year after the transplantation, she is alive and well. Enteroviral infection is common in neonates with high mortality in cases of enteroviral myocarditis. Cardiac transplantation is a treatment option for infants who fail to recover and remain dependent on inotropic support. This is the first report of an infant with out-of-hospital cardiac arrest secondary to enteroviral myocarditis surviving up to cardiac transplantation.

Transcatheter stenting of the right ventricular outflow tract augments pulmonary arterial growth in symptomatic infants with right ventricular outflow tract obstruction and hypercyanotic spells.

We retrospectively reviewed all the children with right ventricular outflow tract obstruction, hypoplastic pulmonary annulus, and pulmonary arteries who underwent stenting of the right ventricular outflow tract for hypercyanotic spells at our institution between January, 2008 and December, 2013; nine patients who underwent cardiac catheterisation at a median age of 39 days (range 12-60 days) and weight of 3.6 kg (range 2.6-4.3 kg) were identified. The median number of stents placed was one stent (range 1-4). The median oxygen saturation increased from 60% to 96%. The median right pulmonary artery size increased from 3.3 to 5.5 mm (-2.68 to -0.92 Z-score), and the median left pulmonary artery size increased from 3.4 to 5.5 mm (-1.93 to 0 Z-scores). Among all, one patient developed transient pulmonary haemorrhage, and one patient had pericardial tamponade requiring drainage. Complete repair of tetralogy of Fallot +/- atrioventricular septal defect or double-outlet right ventricle was achieved in all nine patients. Transcatheter stent alleviation of the right ventricular outflow tract obstruction resolves hypercyanotic spells and allows reasonable growth of the pulmonary arteries to facilitate successful surgical repair. This represents a viable alternative to placement of a systemic-to-pulmonary artery shunt, particularly in small neonates.

Infantile pulmonary capillary haemangiomatosis: a lethal form of pulmonary hypertension.

We describe the cases of two children who both presented in infancy with recurrent severe pulmonary hypertensive crises. Exhaustive clinical work-up failed to identify an underlying aetiology. The patients had no clinical response to steroids, immunoglobulins, or pulmonary vasodilators. Post-mortem examination revealed extensive invasive pulmonary capillary haemangiomatosis. There was no evidence of pulmonary venous occlusive disease. Given the lethal nature of this condition, early consideration of referral to a lung transplant centre should be considered in selected patients.

Regionalization or Access to Care? A Joint Pediatric Heart Care Program That Achieves Both: One Program-Two Sites.

Background: Regionalization of care for children with congenital heart disease has been proposed as a method to improve outcomes. This has raised concerns about limiting access to care. We present the details of a joint pediatric heart care program (JPHCP) which utilized regionalization and actually improved access to care. Methods: In 2017, Kentucky Children's Hospital (KCH) launched the JPHCP with Cincinnati Children's Hospital Medical Center (CCHMC). This unique satellite model was the product of several years of planning, leading to a comprehensive strategy with shared personnel, conferences, and a robust transfer system; "one program-two sites." Results: Between March 2017 and the end of June 2022, 355 operations were performed at KCH under the auspices of the JPHCP. As of the most recent published Society of Thoracic Surgeons (STS) outcome report (through the end of June 2021), for all STAT categories, the JPHCP at KCH outperformed the STS overall in postoperative length of stay, and the mortality rate was lower than expected for the case mix. Of the 355 operations, there were 131 STAT 1, 148 STAT 2, 40 STAT 3, and 36 STAT 4 operations, with two operative mortalities: an adult undergoing surgery for Ebstein anomaly, and a premature infant who died from severe lung disease many months after aortopexy. Conclusions: With a select case mix, and by affiliating with a large volume congenital heart center, the creation of the JPHCP at KCH was able to achieve excellent congenital heart surgery results. Importantly, access to care was improved for those children at the more remote location utilizing this one program-two sites model.

How I do it: Novel technique to "Unmask" and treat congenital portosystemic venous connections in congenital heart disease.

Congenital portosystemic venous connections are rare vascular anomalies that connect the portal and systemic venous circulations. These vascular lesions can lead to complex and varied physiologic manifestations in single-ventricle patients as they progress through the various stages of palliation in the Fontan pathway. Specifically, these connections may be unmasked after a superior cavopulmonary anastomosis operation, but then "re-masked" after Fontan completion. We describe the complex physiology with an illustrative case report and present a novel method to unmask these pathologic connections after Fontan completion to facilitate transcatheter occlusion and resolve downstream symptoms.

Balloon atrial septostomy as initial therapy in pediatric pulmonary hypertension.

Balloon atrial septostomy is a palliative procedure currently used to bridge medically refractory pulmonary hypertension patients to lung transplantation. In the current report, we present balloon atrial septostomy as an initial therapy for high-risk pediatric pulmonary hypertension patients at our institution. Nineteen patients with median age of 4.3 years (range 0.1-14.3 years) underwent balloon atrial septostomy during initial admission for pulmonary hypertension. There were no procedural complications or deaths within 24 h of balloon atrial septostomy. Patients were followed for a median of 2.6 years (interquartile range 1.0-4.8 years). Three (16%) patients died, 3 (16%) underwent lung transplantation, and 1 (5%) underwent reverse Potts shunt. Transplant-free survival at 30 days, 1 year, and 3 years was 84%, 76%, and 67% respectively. This single-center experience suggests early-BAS in addition to pharmacotherapy is safe and warrants consideration in high-risk pediatric pulmonary hypertension patients.

Simulation to Success: Treatment of a 3D Printed Heart Before Complex Systemic Venous Baffle Intervention.

Three-dimensional imaging and printed heart models have become increasingly valuable in the management of patients with complex congenital heart disease. We successfully simulated a stenting procedure on a 3-dimensional printed model of a patient with d-transposition of the great arteries status post-Mustard operation with caval baffle atresia and stenosis. (Level of Difficulty: Advanced.).

Optical Coherence Tomography for the Early Detection of Coronary Vascular Changes in Children and Adolescents After Cardiac Transplantation: Findings From the International Pediatric OCT Registry.

OBJECTIVES: This study sought to describe the initial findings from the International Pediatric Optical Coherence Tomography (OCT) registry in pediatric heart transplant recipients. BACKGROUND: Cardiac allograft vasculopathy (CAV) is a common cause of late graft failure and mortality in pediatric heart transplant recipients. Early diagnosis may improve outcomes. OCT is a high-resolution intravascular imaging technique that has the potential to identify CAV earlier than angiography. METHODS: OCT and angiography of the coronary arteries were performed in pediatric heart transplant recipients at participating centers. Demographics, clinical data, medications, episodes of rejection, and angiographically confirmed CAV were collected for each case. OCT and angiography images were analyzed in a central core imaging laboratory. Intimal thickness and intima/media cross sectional area (I/M CSA) ratios were calculated for each case. Intimal thickness ≥0.25 mm was defined as abnormal and ≥0.4 mm as severe intima thickening. I/M CSA ratio of ≥1 was defined as abnormal. OCT findings were compared to angiographic findings for each case. RESULTS: Across 3 centers, 110 cases were analyzed from 76 patients. Intimal thickening was present in 26 of 110 cases. Eleven of these cases had severe intima thickening (≥0.4 mm) and notably, angiography results were normal in 8 cases. All 5 cases with a median I/M CSA ratio of ≥2 had normal angiography. The maximal intima thickness was ≥0.25 mm in 24% and ≥0.4 mm in 10% of cases. Median I/M CSA ratio was ≥1 for 80% of cases. I/M CSA ratio was significantly higher in cases with concurrent CAV (p = 0.03). Maximal intima thickness was significantly greater in cases with current or previous rejection (p = 0.01). I/M CSA ratio was significantly lower in patients treated with statins (p = 0.01). OCT findings alone prompted a change to medical management in 17% of cases. CONCLUSIONS: OCT provides important insights into coronary vascular changes not detected by angiography in pediatric transplant recipients. The use of OCT for pediatric heart transplant recipients should be further investigated, given its potential to impact the management of CAV.

Predictors of poor outcome among children with heterotaxy syndrome: a retrospective review.

OBJECTIVE: To determine predictors of poor outcome in patients with heterotaxy syndrome. METHODS: A retrospective review of children with heterotaxy syndrome, in a single tertiary paediatric cardiology centre, was conducted between 1 January 1997 and 1 January 2014 to determine predictors of poor outcome. Poor outcome was defined as death, cardiac transplantation or New York Heart Association (NYHA) functional class III or IV. RESULTS: There were 35 patients diagnosed with heterotaxy syndrome, 17 of whom were diagnosed antenatally. 22 patients had right atrial isomerism and 13 had left atrial isomerism. The median age of postnatal diagnosis was 2.5 days old (1 day to 19 months). 12 patients had a poor outcome; 6 patients died, 1 underwent cardiac transplantation and 5 had an NYHA functional class of >III. 5 patients had a biventricular repair and the remaining 30 had a univentricular repair. Type of atrial isomerism, univentricular or biventricular anatomy, severity of atrioventricular valve regurgitation or ventricular dysfunction, obstructed pulmonary venous return, occurrence of arrhythmia and presence of pulmonary atresia did not predict poor outcome. Fetal diagnosis also did not confer a survival advantage. The median duration of follow-up in this cohort was 65 months (2 days to 16.8 years). CONCLUSIONS: Survival for patients with heterotaxy syndrome was 83% over a median follow-up of 65 months. 34% of patients had a poor outcome. None of the variables studied were predictive of death, transplantation or NYHA classification III or IV.

Perinatal management of major congenital heart disease.

Congenital heart disease (CHD) is the most common form of congenital anomaly. Prenatal diagnosis of CHD has been associated with decreased morbidity and mortality for some forms of major CHD. As most cases of major CHD are not identified prenatally, clinical examination of the newborn and pulse oximetry are also important means of identifying more cases. Clinicians must suspect CHD as a diagnosis in a cyanosed or shocked neonate and be familiar with appropriate management, namely the commencement of prostaglandin if a duct dependent cardiac lesion is suspected. Telemedicine can aid prompt diagnosis of CHD and therefore direct appropriate management.