Arrhythmias After Tetralogy of Fallot Repair

Tetralogy of Fallot is the most common cyanotic congenital heart disease, with a good outcome after total surgical correction. In spite of a low perioperative mortality and a good quality of life, late sudden death remains a significant clinical problem, mainly related to episodes of sustained ventricular tachycardia and ventricular fibrillation. Fibro-fatty substitution around infundibular resection, intraventricular septal scar, and patchy myocardial fibrosis, may provide anatomical substrates of abnormal depolarization and repolarization causing reentrant ventricular arrhythmias. Several non-invasive indices based on classical examination such as ECG, signal-averaging ECG, and echocardiography have been proposed to identify patients at high risk of sudden death, with hopeful results. In the last years other more sophisticated invasive and non-invasive tools, such as heart rate variability, electroanatomic mapping and cardiac magnetic resonance added a relevant contribution to risk stratification. Even if each method per se is affected by some limitations, a comprehensive multifactorial clinical and investigative examination can provide an accurate risk evaluation for every patien

Is arrhythmogenic right ventricular cardiomyopathy a paediatric problem too?

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a heart muscle disease that is often familial, characterized by arrhythmias of right ventricular origin, due to transmural fatty or fibrofatty replacement of atrophic myocardium. ARVC is usually diagnosed in the clinical setting between 20 and 40 years of age. The disease is seldom recognised in infancy or under the age of 10, probably because the clinical expression of the disease is normally postponed to youth and adulthood. This review focuses its attention to the pediatric age, defined as the period of life raging from birth to 18 years. During this span of life, ARVC is not so rare as previously supposed and can be identified by applying the same diagnostic criteria proposed for the adult. Ventricular arrhythmias range from isolated ventricular arrhythmias to sustained ventricular tachycardia and fibrillation. Children and adolescents with ARVC must be carefully evaluated and followed-up especially when a family positive history is present, taking into account the high probability during this life-period that asymptomatic affected patients become symptomatic or that arrhythmias worsen during follow-up. The recent identification of the first defective gene opens new avenues for the early identification of affected subjects even when asymptomatic.peer-reviewe

numerical analysis of zno thin layers having rough surface

In this paper an automated procedure for the analysis of Transparent Conductive Oxides (TCO) layers exhibiting rough surfaces is proposed. The method is based on the interaction between MATLAB and the Sentaurus TCAD and is aimed to the reduction of computational efforts needed for full three dimensional analyses. Experiments performed on CVD deposited ZnO layer, showing the reliability of the method for describing their optical properties, are reported. A semi-empirical technique for the extraction of the TCO refractive index is shown as well

Accurate Maximum Power Tracking in Photovoltaic Systems Affected by Partial Shading

A maximum power tracking algorithm exploiting operating point information gained on individual solar panels is presented. The proposed algorithm recognizes the presence of multiple local maxima in the power voltage curve of a shaded solar field and evaluates the coordinated of the absolute maximum. The effectiveness of the proposed approach is evidenced by means of circuit level simulation and experimental results. Experiments evidenced that, in comparison with a standard perturb and observe algorithm, we achieve faster convergence in normal operating conditions (when the solar field is uniformly illuminated) and we accurately locate the absolute maximum power point in partial shading conditions, thus avoiding the convergence on local maxima

A case of cyanotic L-transposition with complete heart block in an adult female who had three in-hospital normal deliveries

A 48-year-old female presented with complete heart block. On evaluation, it was diagnosed as a congenital cyanotic heart disease, namely, L-transposition of great arteries (L-TGA) with Fallot's physiology. She led the normal life of a manual laborer and had three hospital deliveries and yet escaped detection of her cardiac condition

Adult patients with grown-up congenital heart disease: Lights and shadows

GUCH is acronym of grown-up congenital heart of patients who become adults after cardiac surgery. The history of this population is in progress (temporal perspective), and long-term post-surgical follow-up revealed the paradoxical meaning of correction of complex congenital heart disease, because surgery does not restore normality: It prolongs life, improves symptoms, functional capacity, but it is often associated with illness and peculiar needs. Not only survival but also health-related quality of life, which is strictly connected to clinical status, socio-economic situation, psychological conditions, cognitive functions, level of care with particular attention to gender differences. Currently the history of these patients is better known: A multidisciplinary team of cardiologists with specific training in congenital heart disease, psychologists, neurophysiologists, obstetricians, social workers, experts in human science can improve the possibilities of these patients to realize their effective and safe project of life

Neuropsychological Profile in a Large Group of Heart Transplant Candidates

BACKGROUND: Recent studies have reported that patients with end-stage heart disease can have cognitive deficits ranging from mild to severe. Little is known, however, about the relationship between cognitive performance, neurophysiological characteristics and relevant clinical and instrumental indexes for an extensive evaluation of patients with heart failure, such as: left ventricular ejection fraction (LVEF) and other haemodynamic measures, maximum oxygen uptake during cardiopulmonary exercise testing, comorbidities, major cardiovascular risk factors and disease duration. Our purpose was to outline the cognitive profiles of end-stage heart disease patients in order to identify the cognitive deficits that could compromise the quality of life and the therapeutic adherence in end-stage heart disease patients, and to identify the variables associated with an increased risk of cognitive deficits in these patients. METHODS: 207 patients with end-stage cardiac disease, candidates for heart transplant, were assessed by complete neuropsychological evaluation and by electroencephalographic recording with EEG spectral analysis. RESULTS: Pathological scores in one or more of the cognitive tests were obtained by 86% of the patients, while 36% performed within the impaired range on five or more tests, indicating poor performance across a broad range of cognitive domains. The executive functions were the cognitive domain most impaired (70%). Poor performances were not related to the aetiology of heart disease, but rather to cerebral dysfunction secondary to haemodynamic impairment and to comorbidities. CONCLUSIONS: Severe heart failure induces significant neurophysiological and neuropsychological alterations, which may produce an impairment of cognitive functioning and possibly compromise the quality of life of patients and the therapeutic adherence

Investigating the Impact of Cracks on Solar Cells Performance: Analysis based on Nonuniform and Uniform Crack Distributions

The paper investigates the detrimental effect of nonuniform and uniform crack distributions over a solar cell in terms of open-circuit voltage (V_oc), short-circuit current density (J_sc), and output power, the latter under a wide range of irradiance conditions. The experimental procedure to detect the cracks relies on electroluminescence imaging, which is nondestructive and requires a relatively low amount of time. The Griddler software is adopted to translate the EL-taken image into V_oc and J_sc maps. The main findings can be summarized as follows: (i) the nonuniformly- and uniformly-cracked cells are both jeopardized in terms of output power; (ii) the loss corresponding to the cell with nonuniform distribution of cracks is increasingly higher than the uniformly-cracked counterpart as the irradiance hitting the cells grows, and (iii) all cells affected by nonuniform cracks are severely damaged in terms of fingers and rear busbar, which concur to limit the maximum output current

Giant Aneurysm of the Right Atrial Appendage in a 39-Year-Old Woman

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