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Discusses the mapping and ablation of atrial arrhythmias after surgical correction of congenital heart disease guided by a 64-electrode basket catheter. Baseline characteristics of patients involved in the study; Use of activation mapping and entrainment technique to localize the reentry circuit and the critical part to be targeted by radiofrequency ablation.

Globally waste incineration is becoming the predominant treatment method of solid waste. The largest fraction of solid residue of this process is incineration bottom ash (IBA) requiring further treatment before applications such as in the construction industry become feasible. In this study, vitrification of IBA was conducted in a demonstration-scale high-temperature slagging gasification plant fueled with MSW and biomass charcoal as a green auxiliary fuel. High IBA co-feeding rates of up to 491 kg/h (equivalent to 107% of MSW feeding rate) were achieved during the trials. A highly leaching-resistant slag immobilizing heavy metals in the glass-like amorphous structure and recyclable iron-rich metal granules were generated in the process. The heavy metal migration into the solid by-product fractions depended on the IBA feeding rates and process conditions such as cold cap temperature, charcoal-to-ash ratio, and gasifier temperature profile. Slaked lime and activated carbon powder were used in a dry flue gas treatment and stack gas emissions were kept well below Singapore's regulatory limits. Steam from the hot flue gas was generated in a boiler to drive a steam turbine. The application of biomass charcoal instead of fossil fuels or electricity lead to a lower carbon footprint compared to alternative vitrification technologies. The overall results reveal promising application of high temperature slagging gasification process for commercial-scale vitrification of IBA., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Slagging-gasification has received increasing attention as a municipal solid waste treatment technology. Compared with incineration, slagging-gasification can produce valuable syngas and generates by-products that can be easier reusable in different applications in some cases. Among these by-products, the gasification fly ash (GFA) is the only hazardous solid residue to be landfilled. To explore its potential recycling methods and maximize its recycling efficiency, the detailed physicochemical properties of GFA are crucial. This study conducted a comprehensive characterization of six GFA samples and the results were compared with one incineration fly ash (IFA) sample and available data of IFA collected in Singapore in literature. X-ray fluorescence (XRF), and microwave acid digestion (MAD) followed by inductively coupled plasma optical emission spectroscopy (ICP-OES) and inductively coupled plasma mass spectroscopy (ICP-MS) were carried out to determine the physicochemical composition of ashes. X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were applied to identify their mineralogical composition. The hazard of the material was assessed through one-stage batch leaching tests. The results showed that the GFAs and IFA were both mainly composed of calcium compounds and chloride salts. However, GFA contained higher amounts of heavy metals especially lead (Pb) and zinc (Zn) than IFA. Zn contents in tested GFA samples were in a range of 1.4-3.0%, indicating the potential to recover Zn. The Ca(OH) 2 content in GFA samples was up to 24.1%, which could be recovered as a low-grade lime. Based on the characteristics of GFA, a reusing method combining civil engineering utilization and resource recovery was suggested., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

During high temperature slagging gasification of municipal solid waste (MSW), coal coke is typically used as an auxiliary fuel to maintain the high temperature in the gasifier and convert ashes into slag. Herein, biomass charcoal was utilized as a greener and more sustainable auxiliary fuel to replace the coal coke during stable and continuous gasification of MSW. Several monitoring characteristics were assessed, like operating conditions of the gasifier, influence of local MSW properties generated in Singapore, environmental impacts, and main by-products (slag, fly ash and metals). The performance data revealed that the replacement of coal coke with biomass charcoal provided significant environmental benefits. The use of biomass charcoal resulted in 78% less SO 2 emissions, and 22% less generated fly ash because the lower sulfur content in biomass charcoal resulted in a 32% reduced use of sorbent for flue gas treatment. Furthermore, there was clear evidence of a 22% carbon footprint reduction due to replacing fossil fuel as auxiliary fuel. In addition, the slag characteristics demonstrated lower heavy metals leaching as compared to the incineration bottom ash generated from the conventional MSW incineration plant suggesting its great potential in the application as clean and green waste-derived material in the construction industry., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Size and magnetic separation of incineration bottom ash (IBA) are common for ferrous metals recovery, however, their influences on the mineral phase and the element redistribution, and subsequently the induced variation of metal leaching potential herein remain limited understanding. The lack of research in this field may misunderstand IBA performances, cause confused results for comparison among various studies, and potentially lead to biased conclusions. We herein quantitatively investigate the effects of size and magnetic separation on the IBA based on element distribution, leaching behavior, morphology, and mineralogy with statistical analysis. For preparation, sieving was performed with the original IBA (to obtain 7 size-fractions termed as OR1-7, respectively), followed by magnetic separation of each, to further yield magnetic fractions (MF1-7) to discriminate nonmagnetic fractions (NF1-7). In this study, we show that size and magnetic separation may pose significant yet different impacts on different fractions, which would affect their leaching potential concerning their respective downstream applications., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objectives: Sudden cardiac death is a leading cause of mortality in patients with congenital cardiac disease after surgical correction and is potentially preventable. The identification of patients at risk is therefore of major interest. We sought to assess the prognostic value of impaired cardiac autonomic nervous activity in patients with congenital cardiac disease., Methods: Forty-three consecutive patients with congenital cardiac disease were included in this prospective study. Parameters of heart rate turbulence and heart rate variability were calculated from Holter electrocardiograms. In addition, serum brain natriuretic peptide levels were measured. A combined end point of sudden cardiac death or nearly missed sudden cardiac death was used., Results: During a mean follow up of 27 +/- 12.7 months, 5 patients died, and another 2 were successfully resuscitated. On univariate analysis, both brain natriuretic peptide levels and parameters of heart rate variability and heart rate turbulence were associated with impaired prognosis. On multivariate analysis, pathologic heart rate turbulence was found to be the strongest independent risk stratifier (hazard ratio, 61.5; P < .001)., Conclusions: Impaired cardiac autonomic nervous activity is associated with an increased risk of sudden cardiac death in congenital cardiac disease. Our results suggest that heart rate turbulence might be superior to established markers of cardiac autonomic dysfunction, such as heart rate variability. The combined use of heart rate turbulence, heart rate variability, and markers of neurohormonal activation, such as brain natriuretic peptide, might further improve the prognostic value.

Background: Implantable cardioverter defibrillators (ICD) proved to be effective in the prevention of sudden cardiac death in adults. In children, the experience of ICD therapy is limited. This retrospective study was undertaken to review our experience with ICD implantation in children with special consideration of psychosocial impact of this therapy., Methods and Results: Sixteen children (f:5, m:11, median age 12.2 years, range 4-15.9 years) received an ICD. Eleven patients had survived sudden cardiac death with documented ventricular fibrillation (VF) and five patients had sustained ventricular tachycardia (VT) with hemodynamic significance. The underlying heart disease was congenital in 5, hypertrophic cardiomyopathy in 2, myocarditis in 2 and primary electrical in 7 patients. All leads were implanted transvenously. Mean follow up was 43.1 months (range 1-105 months). All patients are alive. In 7 patients, a total of 387 sustained VT episodes were detected by the ICD. At follow-up, 10 inappropriate shocks were delivered in four patients. One early and six late lead revisions were done in seven patients. 12/16 (75%) patients had concomitant antiarrhythmic drug therapy. About half of the adolescents showed signs of depression and/or anxiety., Conclusion: ICD therapy via transvenous access for prevention of sudden cardiac death is feasible and effective even in small children. However, the occurrence of lead complications is significant. Since about half of the adolescents showed signs of depression and/or anxiety, professional psychological surveillance should be considered in these patients.

Objectives: There are reports associating an increased incidence of Wolff-Parkinson-White syndrome with tricuspid atresia. Here we report on electrophysiologic studies in patients with tricuspid atresia and Wolff-Parkinson-White syndrome after the Fontan operation. In these patients the atrial arrhythmia often seen in patients undergoing the Fontan operation triggered atrioventricular re-entrant tachycardia or caused life-threatening arrhythmias., Methods: Five patients with tricuspid atresia after palliation with a modified Fontan operation (atrioinfundibular connections) and Wolff-Parkinson-White syndrome are presented., Results: Four of these patients had symptomatic paroxysmal orthodromic atrioventricular re-entrant tachycardia and a history of syncope; one of them additionally had atrial flutter with 2:1 conduction to the ventricle. A fifth patient presented with a life-threatening broad-complex tachycardia. In electrophysiologic studies an accessory pathway was localized in the right septal area in 3 patients. In 2 patients the accessory atrioventricular pathways were created by means of surgical intervention, connecting the right atrial appendage to the right ventricular outflow tract. All patients could be managed successfully by means of catheter ablation., Conclusions: In patients with tricuspid atresia, there are congenital and surgically acquired accessory pathways responsible for the increased rate of Wolff-Parkinson-White syndrome. Both types of accessory pathways can and should be treated by means of catheter ablation because atrial arrhythmia often seen in patients undergoing the Fontan operation can trigger atrioventricular re-entrant tachycardia or cause life-threatening tachycardia. Congenital accessory pathways should be excluded carefully before surgical intervention for total cavopulmonary anastomosis in patients with tricuspid atresia.

Many patients with congenital cardiac disease need a regular cardiologic follow-up (FU) even after successful primary treatment. Nevertheless, many of them are lost to FU. The present study verifies for the first time the outcome of adults with congenital cardiac disease lost to FU of a specialized institution for >5 years.

A high percentage of cyanotic adults (37%) with cyanotic congenital cardiac disease (CCD) presented with depleted iron stores (13 of 52) or latent iron deficiency (6 of 52), even in a CCD center in which cyanotic patient phlebotomy is mostly avoided. In many of these patients, hypochromia and microcytosis was frequent, whereas hyperchromia and macrocytosis were relatively common.Furthermore, 50% of patients presented with hyperhomocysteinemia, possibly related to folate or B vitamin deficiencies, which may increase red blood cell size and color, explaining the lack of microcytosis and hypochromia in many cyanotic patients with iron deficiency.

Objective: This study determined the quantity and nature of emergencies leading to unscheduled hospital admissions of adults with congenital cardiac disease and their mid-term survival., Results: During 1 year, 429 adults with congenital cardiac diseases were admitted 571 times, and 124 admissions (22%) of 95 patients (22%) were emergency admissions. Fifteen of the 95 patients were seen for the first time in 1 of the participating centers. The underlying anomalies were Fallot's tetralogy and pulmonary atresia (n = 26/7), univentricular heart after Fontan procedure (n = 25), atrial septal defect (n = 18), Eisenmenger syndrome (n = 12), complete transposition (n = 11), and others (n = 25). Indications for admission were cardiovascular complications (n = 103; 83%) (arrhythmia, cardiac failure, syncope, pacemaker problems, pericardial tamponade, and sudden death), infections (n = 8, 6%) (endocarditis, pacemaker infection, pneumonia, and cerebral abscess), acute chest pain (n = 7; 6%), and acute abdominal pain (n = 4; 3%). All patients required immediate emergency care, and 16 patients (17%) required urgent cardiovascular or abdominal surgery. Six patients died during the hospital stay. During a follow-up of 2.9 years (SD 0.8), 16 (18%) of the discharged patients died, and 2 additional patients underwent heart or heart-lung transplantation., Conclusion: Adults with congenital cardiac disease often experience serious emergency situations with a high in-hospital and mid-term post-hospital mortality. Care given by physicians with special expertise is important in this specific group of patients.

Rarely and transient occurring arrhythmia, palpitation, dizziness, syncopes and chest pain frequently cause symptoms and complaints to patients with congenital cardiac defects. The reliable identification of their pathogenesis is often difficult. The study presented here demonstrates the impact of an event recorder for enlightening sporadically occurring complaints and symptoms. Fifty patients (age between 11 and 70 years, median 27 years) were examined with an event recorder (King of Hearts Express, Instromedix, Hillsboro, USA). The patients were referred to an outpatient clinic for congenital cardiac defects in order to clarify unexplained arrhythmia, palpitations, dizziness, or syncope. Included were patients above 10 years of age. Previous cardiac studies (including ECG, exercise-ECG, Holter-Monitoring) were non-diagnostic in all. Altogether 227 ECGs had been recorded. 95% of them were of diagnostic quality. The event recorder afforded ambulatory monitoring and the median duration of monitoring was 22.5 days. The average number of registered events was 4.5 +/- 3.8. In 24% of the patients (n = 12) diagnostic and/or therapeutical consequences resulted: electrophysiological examination (n = 5), drug treatment (n = 4) and pacemaker implantation (n = 3). The event recorder is an important and highly effective tool in diagnosing sporadical transient symptoms and complaints, especially arrhythmias.

The term "Munchausen by proxy" denotes a special form of factitious disorder and a rare kind of child abuse. We present the case of a 12-year-old boy, whose mother's manipulations culminated in his immobilization in a wheelchair and the implantation of a pacemaker. Problems of diagnosis and clinical management of Munchausen by proxy are discussed.

Twenty-one cases (13 male, eight female) of atrial automatic tachycardia (AAT) assessed by standard and Holter-ECG in otherwise healthy infants and children have been documented. AAT was incessant in 12 patients, repetitive in seven, and of undetermined type in the remaining two. The frontal P wave axis suggested an ectopic focus in the high right atrium or right atrial appendage in 13 patients, in the low right atrium in one patient, and in the left atrium in seven patients. Thirteen out of 14 patients with the incessant or undetermined type of AAT were symptomatic, in contrast to only two of seven patients with the repetitive type. All patients were treated with between one and eight (median three) antiarrhythmic drugs. The most effective drug was amiodarone, followed by the class I C antiarrhythmic drugs, propafenone and flecainide. At present, all patients are alive 4 months to 21 years (median 2.5 years) after diagnosis of AAT. Twelve patients are in sinus rhythm, five of them without any medication. Nine patients still have AAT, which, however, is repetitive or intermittent in all but one. In conclusion, AAT is an unusual, and in its incessant form often severely symptomatic arrhythmia, which is resistant to conventional antiarrhythmic medication. However, amiodarone and class I C antiarrhythmic drugs are frequently effective. Since medical treatment with these drugs is often successful, and AAT may resolve completely, a conservative approach is indicated in many cases.

We investigated the clinical course in 35 healthy newborn with premature beats and studied the literature with regard to their frequency, pathogenesis, and therapy with the following results: Investigations with continuous monitoring or long-term ECG registration show a frequency of 7-25%. In literature, almost one-fourth, in our patients one-half of the newborn have ventricular premature beats. These will probably disappear later than atrial premature beats, but their prognosis is not worse. The premature beats of newborn are often complex (blocked or aberrant conduction, bigeminus, tachycardia). Atrial flutter is sometimes associated. In one-half of cases they disappear spontaneously during the first month of life. However, they lasted for longer than 4 months in 7 out of 35 infants. The disorder increased after birth in 2 children, which is unusual. Therapy was indicated if there were signs of heart failure, frequent or increasing rate of tachycardia or atrial flutter. Premature beats do not indicate primary operative delivery. Immaturity of the central and autonomous nervous system and of the conduction-tissue of the heart may be the reason for frequent perinatal premature beats.