Cardiac resternotomy after cardiac surgery in kids: CRACK the chest.

OBJECTIVE: Emergent resuscitation of postoperative paediatric cardiac surgical patients requires specialised skills and multidisciplinary teamwork. Bedside resternotomy is a rare but life-saving procedure and few studies focus on ways to prepare providers and improve performance. We created a multidisciplinary educational intervention that addressed teamwork and technical skills. We aimed to evaluate the efficiency of the intervention to decrease time to perform critical tasks and improve caregiver comfort. METHODS: A simulation-based, in situ resternotomy educational intervention was implemented. Pre-intervention data were collected. Educational aids were used weekly during day and night nursing huddles over a three-month period. All ICU charge nurses had separate educational sessions with study personnel and were required to demonstrate competency in all the critical tasks. Post-intervention simulations were performed after intervention and at 6 months and post-intervention surveys were performed. RESULTS: A total of 186 providers participated in the intervention. There was a decrease in time to obtain defibrillator, setup resternotomy equipment and internal defibrillator paddles and deliver sedation and fluid (all p < 0.05). Time to escort family from the room and obtain blood was significantly decreased after intervention (p < 0.05). There was no difference in time to first dose of epinephrine, defibrillator pads on the patient, or time to call the cardiovascular surgeon or blood bank. Providers reported increased comfort in identifying equipment needed for resternotomy (p < 0.01) and setting up the internal defibrillator paddles (p < 0.01). CONCLUSIONS: Implementation of a novel educational intervention increased provider comfort and decreased time to perform critical tasks in an emergent resternotomy scenario.

Cardiac Fibroma with Asymptomatic Ventricular Arrhythmia in an Adolescent with Gorlin's Syndrome.

Nevoid basal cell carcinoma syndrome (NBCCS), also referred to as Gorlin's syndrome, is an autosomal dominant inherited condition that predisposes affected individuals to various tumors such as cardiac fibromas. Though technically benign, cardiac fibromas may result in malignant arrhythmias and sudden death. The pertinent literature pertaining to pediatric cases of cardiac fibromas and their clinical features were reviewed. We present the case of an asymptomatic teenage with de novo NBCCS who was diagnosed with both NBCCS and cardiac fibroma later in life. The patient was noted to have clinically significant ventricular arrhythmias that were eliminated with tumor resection. There are no established best practice guidelines for the management of cardiac fibromas in patients with NBCCS. Given the risk of sudden arrhythmic death, the presence of ventricular arrhythmias should prompt strong consideration of tumor resection.

Successful Explantation of Berlin Heart Excor in Two Young Children.

Berlin Heart EXCOR ventricular assist device (VAD) implantation in children is widely used as bridge-to-heart transplantation. Berlin left ventricular assist device (LVAD) support as a bridge to recovery is rare. There is a scarcity of literature describing systematic evaluation in pediatric VAD explantation. Patient 1. A 3 month old boy presented with acute heart failure secondary to myocarditis. An echocardiogram demonstrated severely depressed left ventricular function. He required ECMO cannulation and was decannulated 11 days later. He continued to be hemodynamically unstable and required Berlin LVAD implantation with the intent to bridge to transplantation. Patient 2. A 3 month old boy presented initially with a heart rate of 250 beats/min and an electrocardiogram showed multifocal atrial tachycardia. An echocardiogram showed severely decreased left ventricular function. He was placed on ECMO due to unstable hemodynamics. He did not tolerate ECMO decannulation due to persistent chaotic atrial rhythm and underwent Berlin LVAD implantation with the intent to bridge to transplantation. After both patients showed evidence of myocardial recovery, they underwent a weaning protocol that includes: screening, trial-off with echocardiography, and trial-off in the catheterization suite. Our patients met the criteria and underwent successful explantation. Explantation of VAD can be successfully performed even in young children with appropriate candidate selection and a multidisciplinary and systematic approach.

Extracorporeal membrane oxygenation outcomes in children with Williams syndrome: a review of the ELSO registry.

INTRODUCTION: Williams syndrome (WS) results from a microdeletion that usually involves the elastin gene, leading to generalized arteriopathy. Cardiovascular anomalies are seen in 80% of WS patients, including supravalvular aortic stenosis (SVAS), pulmonary artery stenosis (PAS), and pulmonary stenosis (PS). Sudden death associated with procedural sedation and in the perioperative period in WS children have been reported. This study aims to describe extracorporeal membrane oxygenation (ECMO) use in WS children, identify risk factors for hospital mortality of WS patients, and compare outcomes between WS children and non-WS children with SVAS, PAS, and PS. METHODS: Children 0-18 years-old in the Extracorporeal Life Support Organization (ELSO) Registry with a primary or secondary diagnosis of WS, SVAS, PAS, or PAS were included. RESULTS: Included were 50 WS children and 1222 non-WS children with similar cardiac diagnoses. ECMO use increased over time in both groups (p = 0.93), with most cases occurring in the current era. WS children were younger (p = 0.004), weighed less (p = 0.048), had a pulmonary indication for ECMO (50% vs 10%, p < 0.001), and were placed more on high frequency ventilation (p < 0.001) than non-WS patients. Despite reporting a respiratory indication, most (84%) WS patients were placed on VA-ECMO. There were no significant differences between the two groups in terms of pre-ECMO cardiac arrest, ECMO duration, or reason for ECMO discontinuation. Both groups had a mortality rate of 48% (p = 1.00). No risk factors for WS mortality were identified.

Extracorporeal membrane oxygenation for multisystem inflammatory syndrome in children.

Early reports suggested that pediatric COVID-19 cases were less severe in children. Most children requiring intensive care admission in these reports had underlying medical conditions. Shortly after the surge of adult COVID-19 cases in Detroit, Michigan, previously healthy children began to present with shock with multiorgan dysfunction, elevated inflammatory markers, and physical exam findings with features of Kawasaki disease. This disease process was later called multisystem inflammatory syndrome in children (MIS-C.) In this case series, we describe three previously healthy children who presented with severe manifestations of MIS-C, including cardiogenic shock and profound systemic inflammation. These children developed severely depressed myocardial function with end-organ injury and were cannulated to veno-arterial extracorporeal membrane oxygenation (VA-ECMO) due to cardiogenic shock with arrhythmia. All three children improved with VA-ECMO support and anti-inflammatory treatment. All had complete recovery of myocardial function at discharge and 6-month follow-up with no significant morbidity.

Echocardiographic Indicators Associated with Adverse Clinical Course and Cardiac Sequelae in Multisystem Inflammatory Syndrome in Children with Coronavirus Disease 2019.

BACKGROUND: Multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019 causes significant cardiovascular involvement, which can be a determinant of clinical course and outcome. The aim of this study was to investigate whether echocardiographic measures of ventricular function were independently associated with adverse clinical course and cardiac sequelae in patients with MIS-C. METHODS: In a longitudinal observational study of 54 patients with MIS-C (mean age, 6.8 ± 4.4 years; 46% male; 56% African American), measures of ventricular function and morphometry at initial presentation, predischarge, and at a median of 3- and 10-week follow-up were retrospectively analyzed and were compared with those in 108 age- and gender-matched normal control subjects. The magnitude of strain is expressed as an absolute value. Risk stratification for adverse clinical course and outcomes were analyzed among the tertiles of clinical and echocardiographic data using analysis of variance and univariate and multivariate regression. RESULTS: Median left ventricular apical four-chamber peak longitudinal strain (LVA4LS) and left ventricular global longitudinal strain (LVGLS) at initial presentation were significantly decreased in patients with MIS-C compared with the normal cohort (16.2% and 15.1% vs 22.3% and 22.0%, respectively, P < .01). Patients in the lowest LVA4LS tertile (<13%) had significantly higher C-reactive protein and high-sensitivity troponin, need for intensive care, and need for mechanical life support as well as longer hospital length of stay compared with those in the highest tertile (>18.5%; P < .01). Initial LVA4LS and LVGLS were normal in 13 of 54 and 10 of 39 patients, respectively. There was no mortality. In multivariate regression, only LVA4LS was associated with both the need for intensive care and length of stay. At median 10-week follow-up to date, seven of 36 patients (19%) and six of 25 patients (24%) had abnormal LVA4LS and LVGLS, respectively. Initial LVA4LS < 16.2% indicated abnormal LVA4LS at follow-up with 100% sensitivity. CONCLUSION: Impaired LVGLS and LVA4LS at initial presentation independently indicate a higher risk for adverse acute clinical course and persistent subclinical left ventricular dysfunction at 10-week follow-up, suggesting that they could be applied to identify higher risk children with MIS-C.

Repair of a mixed form of supracardiac total anomalous pulmonary venous connection.

Total anomalous pulmonary venous connection is a rare congenital heart defect. We report an infant with a mixed form of supracardiac TAPVC, in whom all pulmonary veins, except the right upper, entered a pulmonary venous confluence that is connected to a vertical vein and drained into the superior vena caval-right atrial junction. Several segmental right upper pulmonary veins entered the superior vena cava, superior to the entry of the vertical vein. Surgical repair consisted of the Warden procedure combined with direct anastomosis of the vertical vein to the left atrium. Separate pulmonary venous drainage pathways decreased the risk of post-operative pulmonary venous obstruction. Our patient had an uneventful post-operative course and encouraging 2-month follow-up echocardiography. Careful follow-up is warranted to detect post-operative complications, including obstruction of the pulmonary venous and cavoatrial anastomoses.

Twin-to-Twin Heart Transplantation: A Unique Event With a 25-Year Follow-Up.

Solid organ transplantation in pediatric patients has been a reality since 1954, when the first kidney transplantation was successfully performed between identical twins. We report the long-term outcomes, with more than 25 years of follow-up, in a patient born with hypoplastic left heart syndrome (HLHS) who received a heart transplant from a dizygotic twin. While we would not wish for this situation to reoccur, we hope that in reporting it, we can add to the discussion surrounding pediatric heart transplantation and the management of HLHS.

Selective inhibition of ATPase activity during contraction alters the activation of p38 MAP kinase isoforms in skeletal muscle.

Muscle contractions strongly activate p38 MAP kinases, but the precise contraction-associated sarcoplasmic event(s) (e.g., force production, energetic demands, and/or calcium cycling) that activate these kinases are still unclear. We tested the hypothesis that during contraction the phosphorylation of p38 isoforms is sensitive to the increase in ATP demand relative to ATP supply. Energetic demands were inhibited using N-benzyl-p-toluene sulphonamide (BTS, type II actomyosin) and cyclopiazonic acid (CPA, SERCA). Extensor digitorum longus muscles from Swiss Webster mice were incubated in Ringer's solution (37°C) with or without inhibitors and then stimulated at 10 Hz for 15 min. Muscles were immediately freeze-clamped for metabolite and Western blot analysis. BTS and BTS + CPA treatment decreased force production by 85%, as measured by the tension time integral, while CPA alone potentiated force by 310%. In control muscles, contractions resulted in a 73% loss of ATP content and a concomitant sevenfold increase in IMP content, a measure of sustained energetic imbalance. BTS or CPA treatment lessened the loss of ATP, but BTS + CPA treatment completely eliminated the energetic imbalance since ATP and IMP levels were nearly equal to those of non-stimulated muscles. The independent inhibition of cytosolic ATPase activities had no effect on contraction-induced p38 MAPK phosphorylation, but combined treatment prevented the increase in phosphorylation of the γ isoform while the α/ß isoforms unaffected. These observations suggest that an energetic signal may trigger phosphorylation of the p38γ isoform and also may explain how contractions differentially activate signaling pathways.

Inhibition of cross-bridge formation has no effect on contraction-associated phosphorylation of p38 MAPK in mouse skeletal muscle.

Mitogen-activated protein kinases (MAPKs), in particular p38 MAPK, are phosphorylated in response to contractile activity, yet the mechanism for this is not understood. We tested the hypothesis that the force of contraction is responsible for p38 MAPK phosphorylation in skeletal muscle. Extensor digitorum longus (EDL) muscles isolated from adult male Swiss Webster mice were stimulated at fixed length at 10 Hz for 15 min and then subjected to Western blot analysis for the phosphorylation of p38 MAPK and ERK1/2. Contralateral muscles were fixed at resting length and were not stimulated. Stimulated muscles showed a 2.5-fold increase in phosphorylated p38 MAPK relative to nonstimulated contralateral controls, and there was no change in the phosphorylation of ERK1/2. When contractile activity was inhibited with N-benzyl-p-toluene sulfonamide (BTS), a specific inhibitor of actomyosin ATPase, force production decreased in both a time- and concentration-dependent manner. Preincubation with 25, 75, and 150 microM BTS caused 78+/-4%, 97+/-0.2%, and 99+/-0.2% inhibition in contractile force, respectively, and was stable after 30 min of treatment. Fluorescence measurements demonstrated that Ca2+ cycling was minimally affected by BTS treatment. Surprisingly, BTS did not suppress the level of p38 MAPK phosphorylation in stimulated muscles. These data do not support the view that force generation per se activates p38 MAPK and suggest that other events associated with contraction must be responsible.