Tricuspid atresia with absent pulmonary valve: A rare form of single ventricle.

Tricuspid atresia with an absent pulmonary valve is a rare congenital cardiac defect. Although extensive pathological reviews have been published in the past, there are only a handful of cases that have been successfully palliated to the stage of Fontan. We hereby describe the successful management of one such case and review the surgical strategies described in the literature.

Aortic migration of Amplatzer Piccolo™ ductal Occluder.

We present the case of a 4-month-old, former 23-week premature baby who underwent patent ductus arteriosus device closure in the cardiac catheterisation lab with an Amplatzer Piccolo™ device at 12 weeks of life. This was complicated by late migration of the device into the aorta resulting in severe obstruction and requiring surgical intervention.

An unusual case of a solitary cardiac myofibroma causing severe right ventricular outflow tract obstruction in an infant.

Cardiac tumours are relatively uncommon, particularly in children. Myofibroma is an extremely rare variety of cardiac tumour, which nearly always arises in the context of infantile myofibromatosis. Herein, we present a case of a solitary cardiac myofibroma causing right ventricular outflow tract obstruction in a 2-month-old male infant.

Utility of the Medtronic microvascular plug™ as a transcatheter implantable and explantable pulmonary artery flow restrictor in a swine model.

BACKGROUND: A surgical pulmonary artery band (PAB) is used to control excessive pulmonary blood flow for certain congenital heart diseases. Previous attempts have been made to develop a transcatheter, implantable pulmonary flow restrictor (PFR) without great success. We modified a microvascular plug (MVP) to be used as a PFR. The objectives of this study were to demonstrate feasibility of transcatheter implantation and retrieval of the modified MVP as a PFR, and compare PA growth while using the PFR versus PAB. METHODS AND RESULTS: The PFR was implanted in eight newborn piglets in bilateral branch pulmonary arteries (PAs). Immediately post-PFR implantation, the right ventricular systolic pressure increased from a median of 20-51 mmHg. Transcatheter retrieval of PFR was 100% successful at 3, 6, and 9 weeks and 50% at 12-weeks post-implant. A left PAB was placed via thoracotomy in four other newborn piglets. Debanding was performed 6-weeks later via balloon angioplasty. On follow-up, the proximal left PA diameters in the PFR and the PAB groups were similar (median 8 vs. 7.1 mm; p = 0.11); albeit the surgical band sites required repeat balloon angioplasty secondary to recurrent stenosis. By histopathology, there was grade II vessel injury in two pigs immediately post-retrieval of PFR that healed by 12 weeks. CONCLUSIONS: Transcatheter implantation and retrieval of the MVP as a PFR is feasible. PA growth is comparable to surgical PAB, which is likely to require reinterventions. The use of the MVP as a PFR in humans has to be trialed before recommending its routine use.

Double aortic arch presenting as neonatal respiratory failure in the delivery room.

Respiratory symptoms are prevalent in vascular ring anomalies, including double aortic arch, which is considered the most common type of vascular ring. However, respiratory failure owing to critical airway obstruction in the neonatal period is rare with few reported cases in the literature. We report a case of a newborn patient who required emergent intubation within the first few hours of life and was later discovered to have a double aortic arch.

Femoral vein homograft as Sano shunt results in improved pulmonary artery growth after Norwood operation.

OBJECTIVE: To evaluate differences in interstage growth of pulmonary arteries between use of polytetrafluoroethylene and femoral vein homograft as Sano shunt during stage-I Norwood palliation. METHODS: A retrospective review of all patients who survived to the second stage following Norwood-Sano operation at two institutions was performed. Either polytetrafluoroethylene or the valved segment of femoral vein homograft was used for construction of the Sano shunt. The size of pulmonary arteries was compared at pre-Glenn catheterisation. RESULTS: A total of 48 neonates with the diagnosis of hypoplastic left heart syndrome or its variants comprised the study population. Femoral vein homograft of 5-6 mm diameter was used in 14 and polytetrafluoroethylene graft of 5 mm was used in 34 patients. The two groups were comparable in terms of preoperative demographics and age at time of pre-Glenn catheterisation (3.9±0.7 versus 3.4±0.8 months, p=0.06). Patients who received femoral vein homograft demonstrated a significantly higher pre-Glenn Nakata index [264 (130-460) versus 165 (108-234) mm2/m2, p=0.004]. The individual branch pulmonary arteries were significantly larger in the femoral vein group (right, 7.8±3.6 versus 5.0±1.2, p=0.014; left, 7.2±2.1 versus 5.6±1.9, p=0.02). There were no differences in cardiac index, Qp:Qs, ventricular end-diastolic pressure or systemic oxygen saturations. CONCLUSIONS: Utilisation of a valved segment of femoral vein homograft as right ventricle to pulmonary artery conduit during Norwood-Sano operation confers better interstage growth of the pulmonary arteries. Further studies are needed to evaluate the impact of femoral vein homograft on single ventricle function.

Effect of thyroid hormone on cardiac function following orthotopic heart transplantation in piglets.

Studies in adult HT have demonstrated improved cardiac function in the recipient following administration of T3 to the donor. The purpose of this experiment was to assess the effects of T3 on the function of the immature donor heart following HT in a piglet model. A total of 32 piglets were divided into 16 donors and 16 recipients. Following creation of brain death, half of the donor piglets were randomized to receive three doses of T3 (0.2 µg/kg) along with hydrocortisone (1 mg/kg). The donor hearts were then transplanted into the recipient piglets on CPB. Duration of survival off CPB, inotrope score, and EF of heart following CPB were evaluated. There were no differences between the two groups in age, weight, pre-brain death EF, T3 levels, and CPB times. Post-CPB survival times were inversely related to the ischemic times in both groups (Pearson r=-0.80, P<.001), and this relationship was not influenced by T3. There was no difference in inotrope score, EF, or biochemical assessment between the two groups. Administration of T3 in combination with hydrocortisone to the brain-dead donor confers no beneficial effect on myocardial function or survival following HT in a piglet model.

Influence of weight at the time of first palliation on survival in patients with a single ventricle.

BACKGROUND: Numerous advances in surgical techniques and understanding of single-ventricle physiology have resulted in improved survival. We sought to determine the influence of various demographic, perioperative, and patient-specific factors on the survival of single-ventricle patients following stage 1 palliation at our institution. METHODS: We conducted a retrospective study of all single-ventricle patients who had undergone staged palliation at our institution over an 8-year period. Data were collected from the Society of Thoracic Surgeons Congenital Heart Surgery database and from patient charts. Information on age, weight at stage 1 palliation, prematurity, genetic abnormalities, non-cardiac anomalies, ventricular dominance, and type of palliation was collected. Information on mortality and unplanned reinterventions was also collected. RESULTS: A total of 72 patients underwent stage 1 palliation over an 8-year period. There were 12 deaths before and one death after stage 2 palliation. There was no hospital mortality following Glenn or Fontan procedures. On univariate analysis, low weight at the time of stage 1 palliation and prematurity were found to be risk factors for mortality following stage 1 palliation. However, multivariable Cox regression analysis revealed weight at stage 1 palliation to be a strong predictor of mortality. The type of stage 1 palliation did not have any influence on the outcome. No difference in survival was noted following the Glenn procedure. CONCLUSION: Low weight has a deleterious impact on survival following stage 1 palliation. This is mitigated by stage 2 palliation. The type of stage 1 palliation itself has no bearing on the outcome.

Common pulmonary vein atresia: report of three cases and review of the literature.

Common pulmonary vein atresia is a rare and usually fatal congenital anomaly, in which the pulmonary veins come together to form a confluence that does not connect to the left atrium. We report our experience with three cases of common pulmonary vein atresia and review the literature on this anomaly. The diagnosis of common pulmonary vein atresia must be entertained in any newborn that presents with cyanosis, refractory acidosis, and decreased systemic perfusion within the first 48 hours of life. Echocardiography is a useful screening tool, but cardiac catheterisation is the preferred diagnostic tool. Common pulmonary vein atresia can be fatal without surgical intervention, but survival after surgery continues to be poor.

Aortic Dissection in a Neonate Receiving Extracorporeal Life Support Therapy: A Case Report.

Extracorporeal life support (ECLS) therapy is increasingly being used to support children with refractory cardiorespiratory failure, but its use is occasionally associated with complications.1 Neonatal aortic dissection in association with ECLS is rare and the clinical sequelae of aortic dissection in neonates are poorly understood. We report a case of extensive type B aortic dissection in a neonate receiving ECLS therapy for refractory cardiogenic shock secondary to tachycardia-induced cardiomyopathy and Wolf Parkinson White (WPW) syndrome. The patient was noted to have aortic dissection along with multiple abdominal organ ischemic injury a day after ECLS arterial cannula position adjustment. The patient was rapidly decannulated from ECLS and the aortic dissection was managed conservatively with good outcome. We discuss our approach and rationale behind conservative management of this rarely reported complication associated with ECLS therapy and discuss available literature.

Impact of Social Determinants of Health on Predictive Models for Outcomes After Congenital Heart Surgery.

BACKGROUND: Despite documented associations between social determinants of health and outcomes post-congenital heart surgery, clinical risk models typically exclude these factors. OBJECTIVES: The study sought to characterize associations between social determinants and operative and longitudinal mortality as well as assess impacts on risk model performance. METHODS: Demographic and clinical data were obtained for all congenital heart surgeries (2006-2021) from locally held Congenital Heart Surgery Collaborative for Longitudinal Outcomes and Utilization of Resources Society of Thoracic Surgeons Congenital Heart Surgery Database data. Neighborhood-level American Community Survey and composite sociodemographic measures were linked by zip code. Model prediction, discrimination, and impact on quality assessment were assessed before and after inclusion of social determinants in models based on the 2020 Society of Thoracic Surgeons Congenital Heart Surgery Database Mortality Risk Model. RESULTS: Of 14,173 total index operations across New York State, 12,321 cases, representing 10,271 patients at 8 centers, had zip codes for linkage. A total of 327 (2.7%) patients died in the hospital or before 30 days, and 314 children died by December 31, 2021 (total n = 641; 6.2%). Multiple measures of social determinants of health explained as much or more variability in operative and longitudinal mortality than clinical comorbidities or prior cardiac surgery. Inclusion of social determinants minimally improved models' predictive performance (operative: 0.834-0.844; longitudinal 0.808-0.811), but significantly improved model discrimination; 10.0% more survivors and 4.8% more mortalities were appropriately risk classified with inclusion. Wide variation in reclassification was observed by site, resulting in changes in the center performance classification category for 2 of 8 centers. CONCLUSIONS: Although indiscriminate inclusion of social determinants in clinical risk modeling can conceal inequities, thoughtful consideration can help centers understand their performance across populations and guide efforts to improve health equity.

Long-Term Health Care Utilization After Cardiac Surgery in Children Covered Under Medicaid.

BACKGROUND: Understanding the longitudinal burden of health care expenditures and utilization after pediatric cardiac surgery is needed to counsel families, improve care, and reduce outcome inequities. OBJECTIVES: The purpose of this study was to describe and identify predictors of health care expenditures and utilization for Medicaid-insured pediatric cardiac surgical patients. METHODS: All Medicaid enrolled children age <18 years undergoing cardiac surgery in the New York State CHS-COLOUR database, from 2006 to 2019, were followed in Medicaid claims data through 2019. A matched cohort of children without cardiac surgical disease was identified as comparators. Expenditures and inpatient, primary care, subspecialist, and emergency department utilization were modeled using log-linear and Poisson regression models to assess associations between patient characteristics and outcomes. RESULTS: In 5,241 New York Medicaid-enrolled children, longitudinal health care expenditures and utilization for cardiac surgical patients exceeded noncardiac surgical comparators (cardiac surgical children: $15,500 ± $62,000 per month in year 1 and $1,600 ± $9,100 per month in year 5 vs noncardiac surgical children: $700 ± $6,600 per month in year 1 and $300 ± $2,200 per month in year 5). Children after cardiac surgery spent 52.9 days in hospitals and doctors' offices in the first postoperative year and 90.5 days over 5 years. Being Hispanic, compared with non-Hispanic White, was associated with having more emergency department visits, inpatient admissions, and subspecialist visits in years 2 to 5, but fewer primary care visits and greater 5-year mortality. CONCLUSIONS: Children after cardiac surgery have significant longitudinal health care needs, even among those with less severe cardiac disease. Health care utilization differed by race/ethnicity, although mechanisms driving disparities should be investigated further.

Chronic Medication Burden After Cardiac Surgery for Pediatric Medicaid Beneficiaries.

BACKGROUND: Congenital heart defects are the most common and resource-intensive birth defects. As children with congenital heart defects increasingly survive beyond early childhood, it is imperative to understand longitudinal disease burden. OBJECTIVES: The purpose of this study was to examine chronic outpatient prescription medication use and expenditures for New York State pediatric Medicaid enrollees, comparing children who undergo cardiac surgery (cardiac enrollees) and the general pediatric population. METHODS: This was a retrospective cohort study of all Medicaid enrollees age <18 years using the New York State Congenital Heart Surgery Collaborative for Longitudinal Outcomes and Utilization of Resources database (2006-2019). Primary outcomes were total chronic medications per person-year, enrollees per 100 person-years using ≥1 and ≥3 medications, and medication expenditures per person-year. We described and compared outcomes between cardiac enrollees and the general pediatric population. Among cardiac enrollees, multivariable regression examined associations between outcomes and clinical characteristics. RESULTS: We included 5,459 unique children (32,131 person-years) who underwent cardiac surgery and 4.5 million children (22 million person-years) who did not. More than 4 in 10 children who underwent cardiac surgery used ≥1 chronic medication compared with approximately 1 in 10 children who did not have cardiac surgery. Medication expenditures were 10 times higher per person-year for cardiac compared with noncardiac enrollees. Among cardiac enrollees, disease severity was associated with chronic medication use; use was highest among infants; however, nearly one-half of adolescents used ≥1 chronic medication. CONCLUSIONS: Children who undergo cardiac surgery experience high medication burden that persists throughout childhood. Understanding chronic medication use can inform clinicians (both pediatricians and subspecialists) and policymakers, and ultimately the value of care for this medically complex population.

Giant mediastinal teratoma in a young infant: a case report.

Background: Giant mediastinal tumors in the pediatric population can pose unique challenges for resection such as cardiovascular collapse on induction of anesthesia and injury to surrounding structures that may be compressed, displaced, or invaded by the mass. Principles that must be borne in mind during removal of giant mediastinal masses include: appropriate cross-sectional imaging to define extent of mass; airway control during induction of anesthesia; a multidisciplinary collaborative approach including cardiothoracic surgery; preparation for urgent sternotomy; plan for peripheral cannulation to institute cardiopulmonary bypass if needed; preservation of neurovasculature structures during dissection; complete resection whenever possible. While complete resection is desirable and results in an excellent prognosis, it may not be achievable especially if the tumor encases coronary arteries, and it is acceptable to leave small amounts of tumor behind. Case Description: Here we present a case describing surgical management of a giant mediastinal teratoma in a two-month-old female. The patient was found to have a large mediastinal mass during workup for cough and noisy breathing. She underwent preoperative echocardiogram demonstrating normal cardiac function followed by uncomplicated, open resection of the mass. Conclusions: Giant mediastinal tumors give rise to unique challenges for resection in small infants. The principles of airway control, preparation for urgent sternotomy, preparation for peripheral cardiopulmonary bypass cannulation, and preservation of neurovasculature during dissection must be borne in mind.

Multivalvular Endocarditis With Abscess: A Wild Goose Chase.

We report a case of Streptococcus mutans multivalvular infective endocarditis complicated by aortic root abscess and septic emboli in a 19-year-old male with a bicuspid aortic valve. This case illustrates the progression of untreated subacute bacterial endocarditis and highlights the importance of ongoing clinical suspicion for infective endocarditis in patients with underlying valvular defects.

Elevated Levels of Urinary Biomarkers TIMP-2 and IGFBP-7 Predict Acute Kidney Injury in Neonates after Congenital Heart Surgery.

Objectives This article investigated the utility of urine biomarkers tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor binding protein-7 (IGFBP-7) in identifying acute kidney injury (AKI) in neonates after congenital heart surgery (CHS). TIMP-2 and IGFBP-7 are cell cycle arrest proteins detected in urine during periods of kidney stress/injury. Methods We conducted a single-center, prospective study between September 2017 and May 2019 with neonates undergoing CHS requiring cardiopulmonary bypass (CPB). Urine samples were analyzed using NephroCheck prior to surgery and 6, 12, 24, and 96 hours post-CPB. All patients were evaluated using the Acute Kidney Injury Network (AKIN) criteria. Wilcoxon rank sum tests were used to compare the medians of the [TIMP-2*IGFBP-7] values in the AKIN negative and positive groups at each time point. Receiver operating characteristic curves were used to measure how well the [TIMP-2*IGFBP-7] values predict AKIN status. Results Thirty-six patients were included. No patients met the AKIN criteria for AKI preoperatively. Postoperatively, 19 patients (53%) met the AKIN criteria for AKI diagnosis: 13 (36%) stage 1, 5 (14%) stage 2, and 1 (3%) stage 3. None required renal replacement therapy. At the 24-hour time points, patients who met the AKIN criteria for AKI had a statistically significantly higher [TIMP-2*IGFBP7] values than the patients without AKI (1.1 vs. 0.27 [ng/mL] 2 /1,000) at 24 hours (adj- p = 0.0019). Conclusion AKI is a serious complication associated with adverse outcomes in patients undergoing cardiac surgery. [TIMP-2*IGFBP-7] urinary level 24 hours after CPB is a good predictor of AKI in this population.

Ebstein's anomaly in the neonate.

Ebstein's anomaly is a rare congenital heart defect characterized by apical displacement of the tricuspid valve and reduced volume of the true functional right ventricle. In its most severe form, the disease presents as right heart failure and cyanosis in the neonate. Although many of these neonates can be managed conservatively, surgical intervention may become necessary in the sickest of them. Surgical intervention in this subgroup can be challenging and requires meticulous appreciation of the anatomy and physiology on a case to case basis. Multicenter studies are required to define a uniform algorithm and approach towards these patients.

The failing Fontan.

Nearly 50 years back, Francis Fontan pioneered an operation for tricuspid atresia that bears his name today. The operation has since undergone numerous modifications and continues to be widely applied to an array of single ventricles. Despite restoring normal oxygen levels in the body, the operation creates a neoportal system where adequate cardiac output can be generated only at the expense of increased systemic venous congestion. This results in slow but relentless damage to the end organ systems especially the liver. Continuous surveillance of the patient to monitor this circulation, that will ultimately fail, is of paramount importance. Timely medical and cardiac catheterization and surgical intervention can extend the life span of Fontan patients. Ultimately a change of the hemodynamic circuit in the form of heart transplantation or ventricular assist device will be required to salvage the failing Fontan circuit.

Impact of Different Cardiopulmonary Bypass Strategies on Renal Injury After Pediatric Heart Surgery.

BACKGROUND: The purpose of this study is to compare the incidence and severity of acute kidney injury (AKI) after open heart surgery in neonates and infants for two different cardiopulmonary bypass (CPB) strategies. METHODS: In all, 151 infants undergoing cardiac surgery were prospectively enrolled between June 2017 and June 2018 at two centers, one using conventional CPB (2.4 L · min-1 · m-2, 150 mL · kg-1 · min-1) with reduction of flow rates with moderate hypothermia and with a targeted hematocrit greater than 25% (center 1, n = 91), and the other using higher bypass flow rates (175 to 200 mL · kg-1 · min-1) and higher minimum hematocrit (greater than 32%) CPB (center 2, n = 60). The primary endpoint was the incidence of postoperative AKI as defined by Acute Kidney Injury Network criteria and risk factors associated with AKI. RESULTS: Preoperative characteristics and complexity of surgery were comparable between centers. The overall incidence of early postoperative AKI was 10.6% (16 of 151), with 15.4% (14 of 91) in center 1 and 3.3% (2 of 60) in center 2 (P = .02). Mean lowest flow rates on CPB were 78 mL · kg-1 · min-1 vs 118 mL · kg-1 · min-1 and mean highest hematocrit on separation from CPB were 33% vs 43% at center 1 and 2, respectively (P < .001). Center 1 used less packed red blood cells but more fresh frozen plasma than center 2 (P = .001). By multivariate analysis, only lower flows on CPB (78 vs 96 mL · kg-1 · min-1, P = .043) and lower hematocrit at the end of CPB (33% vs 37%, P = .007) were associated with AKI. CONCLUSIONS: In this contemporary comparative study, higher flow rates and higher hematocrit during cardiopulmonary bypass were associated with better preservation of renal function.