This is an electrocardiological study, based on electrocardiographic analysis of new cases as well as on a review of some features, hitherto unrecognized or not stressed, in subjects with these disorders, that may help throw more light on them. In six cases studied personally using intracardiac electrography - the technique of His bundle electrography - the contribution and relevance of this method will be analysed, and the results compared with the conclusions drawn from other contemporary work in this field. Thus, the clinical presentation of the cases, and of these syndromes, receives secondary attention, and more detailed analysis only when appropriate to substantiate the main burdens of the thesis. These case reports appear separately in Section c. The mechanism of production of arrhythmias is becoming much better understood, and some of the diagnostic measures that are discussed in this work provide a clearer picture of their genesis. It is not proposed to embark upon a detailed consideration of anti-arrhythmic therapy in these syndromes, but the general principles will be discussed, and special reference will also be made to some new developments in this field.

Propranolol, a first-generation nonselective β-adrenoceptor blocking agent, is commonly used to treat pediatric arrhythmias. Atenolol, relatively long-acting, cardioselective β-adrenoceptor blocking agent, has been successfully used in adults with supraventricular tachycardia (SVT). There is only one report on the use of atenolol in children with SVT, and our report is on the first long-term prospective study to evaluate the use of atenolol in children. A group of 22 children <18 years of age with clinical SVT were enrolled in the study. The tachycardia was documented on electrocardiograms in each case and was confirmed by electrophysiologic studies in some. Once- a-day oral atenolol was started as a monotherapy. Of the 22 children with various types of SVT, 13 (59%) were well controlled on long-term oral atenolol therapy. The effective dose of atenolol ranged between 0.3 and 1.3 mg/kg/day (median effective dose 0.7 mg/kg/day). Five children had some adverse effects. However, none in the successful group of 13 patients required drug discontinuation because of such effects. Once-a-day oral atenolol as a monotherapy is effective and relatively safe for long-term management of SVT during childhood. It is an attractive alternative β- adrenoceptor blocking agent for the management of pediatric arrhythmias.

The location of accessory pathways in Wolff-Parkinson-White syndrome patients is performed manually during open heart surgery at Groote Schuur Hospital, using a hand-held roving electrode. This manual procedure is slow and tedious, prolonging the operation and the time for which the patient remains on cardiac bypass. A multichannel electrogram acquisition and display system with a storage facility would significantly reduce the time taken and improve the reliability of locating the accessory pathways. Having considered a number of currently available cardiac mapping systems it was decided that a new system be developed for specific application within Groote Schuur Hospital. The main design goals of this system are to improve accuracy, increase reliability and enhance the speed of the entire mapping procedure with direct benefit to staff and patients. The system is based on an IBM compatible computer and allows for the acquisition of a maximum of thirty-two electrogram inputs. A typical configuration would acquire twenty epicardial, two references (one each from atrium and ventricle), one roving electrode and two surface lead signals. The epicardial signals are obtained from a custom-built electrode belt which is placed around the heart over the atrioventricular groove. The project includes the development of front-end hardware and software for processing, display and storage of electrogram signals. The relative activation times of the signals are displayed under software control in order to facilitate the location of any accessory pathway(s).

Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 5 uppsatser.

Made available in DSpace on 2014-06-11T19:24:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-01-31Bitstream added on 2014-06-13T20:31:48Z : No. of bitstreams: 1 garbelinijunior_b_me_botfm.pdf: 899004 bytes, checksum: 3e76b67a9e7829e0f9fe15812c489d4f (MD5) / Universidade Estadual Paulista (UNESP) / As arritmias cardíacas são uma importante causa de morte relacionada ao sistema cardiovascular. Entre os vários tipos de arritmias, a Síndrome de Wolff-Parkinson-White se destaca por crises recorrentes de taquicardia, que acontecem com mais frequência no primeiro ano de vida, na adolescência e nas pessoas acima dos 60 anos. Eventualmente, a morte súbita pode ser uma manifestação dessa síndrome, o que acontece mais frequentemente em adultos jovens. A ablação por cateter com radiofrequência tem sido amplamente utilizada nos pacientes com recorrência das taquicardias, pacientes reanimados de morte súbita, pacientes pouco sintomáticos e nos assintomáticos. Avaliar a efetividade e a segurança da ablação por cateter com radiofrequência comparada ao tratamento com antiarrítmicos para pacientes com Síndrome de Wolff-Parkinson-White. Revisão sistemática de estudos clínicos aleatorizados, seguindo a metodologia da Colaboração Cochrane. Realizamos, nas principais bases de dados, uma estratégia de busca para a identificação de estudos clínicos prospectivos, aleatorizados que compararam ablação por cateter versus tratamento com antiarrítmico. Os artigos foram recuperados eletronicamente e manualmente por meio de referências. Dois revisores, independentemente, avaliaram os artigos, excluindo os que não tinham o escopo dessa revisão. 222 artigos foram identificados pela estratégia de busca. Todos os artigos foram excluídos. Não encontramos evidências na literatura que comprovem que a ablação por cateter é mais efetiva e segura que o tratamento antiarrítmico para todos os portadores de Síndrome de Wolff-Parkinson-White / Cardiac arrhythmias are an important cause of death related to cardiovascular system. Among the various types of arrhythmias, Wolff-Parkinson-White syndrome is distinguished by recurrent episodes of tachycardia that occur more frequently in the first year of life, in adolescence and in people over 60 years old. Eventually, sudden death can be a manifestation of this syndrome, which happens more often in young adults. The radiofrequency catheter ablation has been widely used in patients with recurrence of tachycardia, patients resuscitated from sudden death, mildly symptomatic and asymptomatic patients. To evaluate the effectiveness and safety of radiofrequency catheter ablation compared with antiarrhythmic treatment for Wolff-Parkinson-White syndrome patients. A systematic review of randomized clinical trials, following the methodology of the Cochrane Collaboration. We carried out a search strategy in the main databases to identify randomized prospective clinical trials comparing catheter ablation versus antiarrhythmic therapy. The articles were retrieved electronically and manually by reference. In an independent manner, two reviewers evaluated the articles, excluding those that did not have the scope of this review. 222 articles were identified by search strategy. All articles were excluded. In the literature, it was found no evidence that catheter ablation is more effective and safer than antiarrhythmic treatment for all patients with Wolff-Parkinson-White syndrome

Orientador: Antônio José Maria Cataneo / Coorientador: Paulo Eduardo de Oliveira Carvalho / Banca: Olavo Ribeiro Rodrigues / Banca: Márcio Nobrega / Resumo: As arritmias cardíacas são uma importante causa de morte relacionada ao sistema cardiovascular. Entre os vários tipos de arritmias, a Síndrome de Wolff-Parkinson-White se destaca por crises recorrentes de taquicardia, que acontecem com mais frequência no primeiro ano de vida, na adolescência e nas pessoas acima dos 60 anos. Eventualmente, a morte súbita pode ser uma manifestação dessa síndrome, o que acontece mais frequentemente em adultos jovens. A ablação por cateter com radiofrequência tem sido amplamente utilizada nos pacientes com recorrência das taquicardias, pacientes reanimados de morte súbita, pacientes pouco sintomáticos e nos assintomáticos. Avaliar a efetividade e a segurança da ablação por cateter com radiofrequência comparada ao tratamento com antiarrítmicos para pacientes com Síndrome de Wolff-Parkinson-White. Revisão sistemática de estudos clínicos aleatorizados, seguindo a metodologia da Colaboração Cochrane. Realizamos, nas principais bases de dados, uma estratégia de busca para a identificação de estudos clínicos prospectivos, aleatorizados que compararam ablação por cateter versus tratamento com antiarrítmico. Os artigos foram recuperados eletronicamente e manualmente por meio de referências. Dois revisores, independentemente, avaliaram os artigos, excluindo os que não tinham o escopo dessa revisão. 222 artigos foram identificados pela estratégia de busca. Todos os artigos foram excluídos. Não encontramos evidências na literatura que comprovem que a ablação por cateter é mais efetiva e segura que o tratamento antiarrítmico para todos os portadores de Síndrome de Wolff-Parkinson-White / Abstract: Cardiac arrhythmias are an important cause of death related to cardiovascular system. Among the various types of arrhythmias, Wolff-Parkinson-White syndrome is distinguished by recurrent episodes of tachycardia that occur more frequently in the first year of life, in adolescence and in people over 60 years old. Eventually, sudden death can be a manifestation of this syndrome, which happens more often in young adults. The radiofrequency catheter ablation has been widely used in patients with recurrence of tachycardia, patients resuscitated from sudden death, mildly symptomatic and asymptomatic patients. To evaluate the effectiveness and safety of radiofrequency catheter ablation compared with antiarrhythmic treatment for Wolff-Parkinson-White syndrome patients. A systematic review of randomized clinical trials, following the methodology of the Cochrane Collaboration. We carried out a search strategy in the main databases to identify randomized prospective clinical trials comparing catheter ablation versus antiarrhythmic therapy. The articles were retrieved electronically and manually by reference. In an independent manner, two reviewers evaluated the articles, excluding those that did not have the scope of this review. 222 articles were identified by search strategy. All articles were excluded. In the literature, it was found no evidence that catheter ablation is more effective and safer than antiarrhythmic treatment for all patients with Wolff-Parkinson-White syndrome / Mestre