Taquicardia ventricular polimórfica catecolaminérgica com necessidade de implante de cardiodesfibrilador implantável (CDI): Um relato de caso / Ventricular Catecolaminergic Polymorphic Tachycardia (VCPT) with ICD implantation requirement: A case report

Relato de caso de uma paciente do sexo feminino, com 16 anos de idade à ocasião de sua admissão no Instituto de Cardiologia. A mesma foi encaminhada por serviço de saúde externo devido a síncopes durante atividade física e foi submetida à investigação, com diagnóstico final de taquicardia ventricular catecolaminérgica. Após a definição diagnóstica, foi realizado tratamento medicamentoso com betabloqueador, sendo necessário o implante de marcapasso definitivo por conta da incompetência cronotrópica secundária ao tratamento farmacológico instituído. Posteriormente, por persistência das arritmias ventriculares mesmo com o uso de terapia otimizada, optou-se por realizar um implante de CDI

Case report of a 16-year-old female patient at the time of her admission to the Institute of Cardiology. She was referred by an external healthcare service due to syncope during physical activity and was submitted to the investigation with a final diagnosis of catecholaminergic ventricular tachycardia. Once the diagnosis was established, the patient was administered a beta-blocker and definitive pacemaker implant was required due to chronotropic incompetence secondary to drug therapy. Subsequently, due to the persistence of ventricular arrhythmias despite the use of optimized therapy, we decided to implant an ICD

Validação dos sistemas computadorizados empregados na determinação dos enantiômeros do nadolol e dos homólogos da ivermectina e da abamectina / Validation of the computer systems used in the determination of nadolol enantiomers and homologous of ivermectin and abamectin

O nadolol é um agente bloqueador de receptores ß-adrenérgicos empregado principalmente, na "angina pectoris", hipertensão, certas arritmias cardíacas e no tratamento do glaucoma (SING, 2006). A ivermectina e a abamectina são fármacos que apresentam ação antiparasitária (SHOOP, 1995). Na presente pesquisa, a cromatografia em fase líquida de alta eficiência foi uma das técnicas estudadas para a quantificação dos enantiômeros do nadolol e dos homólogos presentes na abamectina e ivermectina. A versatilidade desta técnica reside no grande número de fases estacionárias existentes, as quais possibilitam análises, separações e determinações quantitativas de uma ampla gama de compostos com alta eficiência (Aquino Neto e Nunes, 2003). Para identificação dos enantiômeros do nadolol foi utilizado o dicroísmo circular que permite a determinação da configuração absoluta de enantiômeros (LIMA, 1997). Para os enantiômeros do nadolol e dos homólogos presentes na abamectina e na ivermectina também foram realizados testes para desenvolvimento de uma metodologia de quantificação por meio de uma técnica relativamente recente chamada de eletroforese capilar (EC), a qual tem alcançado desde sua introdução um rápido desenvolvimento e ampla aplicação na análise de fármacos em medicamentos (SANTORO, 2000). Para a comprovação da qualidade e segurança dos sistemas computadorizados dos equipamentos de cromatografia em fase líquida de alta eficiência (CLAE) e de eletroforese capilar (EC) foram efetuadas, neste trabalho, as respectivas validações. Após esta validação, pode-se confirmar o correto funcionamento de um software, e suas interações com o hardware, onde devem ser levados em consideração, dentre outros, os aspectos relacionados à infra-estrutura, segurança e manutenção de dados (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2010). As metodologias analíticas desenvolvidas a para quantificação do nadolol, abamectina e ivermectina por cromatografia em fase líquida de alta eficiência foram validadas. A validação analítica deve garantir, por meio de estudos experimentais, que o método atenda às exigências das aplicações analíticas, assegurando a confiabilidade dos resultados. Para tanto, o método deve apresentar especificidade, linearidade, intervalo, precisão, sensibilidade, limite de quantificação e detecção, exatidão, adequados à análise (AGÊNCIA NACIONAL DE VIGILÂNCIA SANITÁRIA, 2003). Portanto, o objetivo proposto nesta pesquisa é primeiramente a validação dos sistemas computadorizados dos equipamentos de cromatografia em fase líquida de alta eficiência (CLAE) e de eletroforese capilar (EC). Para isto, serão desenvolvidos e validados os métodos analíticos de separação, identificação e quantificação dos enantiômeros do nadolol e dos homólogos presentes na abamectina e na ivermectina, em medicamentos, empregando as técnicas analíticas selecionadas

Nadolol is a blocking agent with activity in the ß -adrenergic receptors. It is mainly used in angina, hypertension, certain heart arrhythmias and in the treatment of glaucoma (SING, 2006). Ivermectin and abamectin are drugs with antiparasitic activity (SHOOP, 1995). In the present research, high performance liquid chromatography is one of the techniques used in the quantification of the enantiomers of nadolol and homologues present in abamectin and ivermectin. The versatility of this technique and the large number of existing stationary phases, enables the separation and quantitative determination of a wide range of compounds with high efficiency (Aquino Neto e Nunes, 2003). For identification of the nadolol enantiomers, circular dichroism was used which allows the determination of the absolute configuration of the enantiomers (LIMA, 1997). Nadolol enantiomers and the homologues present in abamectin and ivermectin will be also quantified by capillary zone electrophoresis (CE), a separation technique relatively recent, which has achieved, since its introduction, a wide application in the analysis of drugs in pharmaceutical preparations (SANTORO, 2000). In order to assure the quality of the analytical results, the computer systems of the liquid chromatograph and capillary electrophoresis equipments, must be validated prior to the analytical methods validation. Computer systems validation is used to verify and confirm the proper operation of softwares, and their interactions with the hardwares, besides the infrastructure, safety and storage of data (AGÊNCIA NACIONAL DE VIGILÂNIA SANITÁRIA, 2010). The analytical methodologies developed for quantification of nadolol, abamectin, ivermectin by using high efficiency liquid chromatography and capillary electrophoresis were validated. The analytical methods validation should ensure, through experimental studies, that the method meets the requirements for analytical applications, ensuring the reliability of the results. Parameters like, specificity, linearity, range, accuracy, sensitivity, limits of detection and quantification and accuracy, must be determined (AGÊNCIA NACIONAL DE VIGILÂNCIA SANITÁRIA, 2003). The objective of this study is to validate the computer systems of the high performance liquid chromatograph and capillary electrophoresis equipments and then to develop and validate analytical methods for separation, identification and quantification of nadolol enantiomers and the homologues of abamectin and ivermectin

Transmissão hereditária da morte súbita cardíaca nas canalopatias / Hereditary transmission of sudden cardiac death in channelopathies

O caso clínico sugere uma forma rara de canalopatia mista, cujo sintoma clínico e eletrocardiográfico indicava taquicardia ventricular polimórfica catecolaminérgica (TVPC). Porém, ao realizar o teste ergométrico, no pós-esforço, quando há predomínio do sistema nervoso parassimpático, nota-se a indução de eletrocardiograma (ECG) compatível com Brugada do tipo I. Outro aspecto importante foi a transmissão hereditária observada neste caso, em que os avós do paciente eram primos de primeiro grau e houve seis casos de morte súbita cardíaca (MSC) nas gerações subsequentes, com irmão que teve MSC aos 5 anos durante uma crise de choro, mostrando um importante fator genético e familiar relacionado às canalopatias.

The clinical case suggests a rare form of mixed channelopathy, whose clinical and electrocardiographic symptom suggested catecholaminergic polymorphic ventricular tachycardia (CPVT). However, when the exercise test was performed, during post-exercise, where there is a predominance of the parasympathetic nervous system, there was an electrocardiogram (ECG) induction compatible with Brugada type I. Another important aspect was the hereditary transmission observed in this patient, whose grandfathers were first cousins, and 6 cases of sudden cardiac death (SCD) were observed in subsequent generations and one brother had SCD at 5 years of age during a crying episode, showing an important genetic and familial factor related to channelopathies.

[ role of adrenoceptors in the electrophysiological effects of hydroalcoholic extract of Citrus bigaradia in experimental model of atrial fibrilation of isolated atrioventricular node of rabbits]

Preliminary studies have been established to examine the cardiotonic effect of Citrus bigaradia extract, by implenenting various mechanisms. The functional protective role of this plant against supraventricuiar tachyarrhythmia remains to be determined.The present study is designed to assess the role of hydroalcoholic extract of Citrus bigaradia by modifing the electrophysiological properties of atrioventricular node, during simulated experimental atrial fibrillation in rabbits and also, to determine the role of adrenoceptores regarding effects of Citrus bigaradia on the AV node. In this present study, Newsland male rabbits [1.5-2 kg] was used. Programmed stimulation protocols [Recovery, Wenckbach, Atrial fibrilation and Zone of concealment] were applied in two groups [N=23] to assess electrophysiological properties of isolated rabbit AV node. In the first group [N=10], different concentrations of hydroalcoholic extract of Citrus bigaradia were added to thyrods to detect nodal concealed conduction. In the second group [N=13], the effects of extracts [54-108 mg/L] were analysied in the presence of beta-adereceptor blocker [Nadolol 2 micro m]. AF protocol was simulated by high-rate atrial pacing with random coupling intervals [range 75-125 ms]. All data have been shown as Mean +/- SE. Citrus bigaradia, had biphasic concentration-effect pattern, such as in low and intermediate concentrations [0.8-3.2 mg/L], shortened nodal functional refractory period and Wenckebach. We observed a non-significant decrease in the average H-H intervals and numbers of concealed beats in all concentrations of Citrus bigaradia. Zone of concealment was shortened by this plant. Nadolol [2 micro m] prevented the whole effects of Citrus bigaradia on the nodal conduction time, refractoriness and concealed conduction. The above results indicate the potential pro-arrhythmic effects of Citrus bigaradia in worsing supraventricuiar tachyarrhythmia. The effects of plant to decrease the AV-nodal refractory period and concealment zone may be considered the major mechanism of this plant. At least some parts of effects of Citrus is mediated through beta-adrenoceptores

Correlation between absorption rates of beta-adrenoreceptor antagonists in rat small intestine and their molecular structures / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To study the correlation between the absorption rate constants of beta-adrenoreceptor antagonists in rat small intestinal segments and their molecular structural parameters.</p><p><b>METHODS</b>The net atomic charges and the molecular volumes of 11 beta-adrenoreceptor antagonists were obtained with the semiempirical self-consistent field molecular orbital calculation CNDO/2 method and Mont Carlo method respectively, using the minimum energy conformation obtained from the optimization of the standard molecular geometry with the molecular mechanics MM+ method. The stepwise multiple regression analysis was used to obtain the correlation equations.</p><p><b>RESULTS</b>The absorption rate constants of beta-adrenoreceptor antagonists in rat jejunum or ileum were well linearly correlated with the sum of the net charges of all hydrogen atoms and the molecular volumes. The beta-adrenoreceptor antagonist with higher lipophilicity, weaker hydrogen-bonding potential,and smaller molecular volume had greater absorption rate constants.</p><p><b>CONCLUSION</b>The absorption rate constants of beta-adrenoreceptor antagonists in rat small intestinal segments are mainly related with their lipophilicity,hydrogen-bonding potential and molecular size.</p>

Taquicardia ventricular polimórfica catecolaminérgica. Um importante diagnóstico em crianças com síncope e coração estruturamente normal / Catecholaminergic polymorphic ventricular tachycardia. An important diagnosis in children with syncope and normal heart

Syncope in children is primarily related to vagal hyperreactivity, but ventricular tachycardia (VT) way rarely be seen. Catecholaminergic polymorphic VT is a rare entity that can occur in children without heart disease and with a normal QT interval, which may cause syncope and sudden cardiac death. In this report, we describe the clinical features, treatment, and clinical follow-up of three children with syncope associated with physical effort or emotion and cathecolaminergic polymorphic VT. Symptoms were controlled with beta-blockers, but one patient died suddenly in the fourth year of follow-up. Despite the rare occurrence, catecholaminergic polymorphic VT is an important cause of syncope and sudden death in children with no identified heart disease and normal QT interval

Modalidades terapêuticas na doença de Basedow-Graves / Therapeutical approaches in Basedow-Graves disease

Neste artigo säo analisadas as três grandes modalidades terapêuticas do hipertireoidismo - o tratamento clínico, o radioiodo e a cirurgia -, discutindo-se detalhadamente cada uma delas, enfocando seus mecanismos de açäo, vantagens e desvantagens, principais indicaçöes e contra indicaçöes. A abordagem terapêutica também será analisada em grupos especiais como neonatos, crianças e adolescentes, gestantes e idosos

Assessment of different therapeutic modalities in prevention of variceal rebleeding

To assess the efficacy of some therapeutic modalities in 2ry prevention of oesophageal variceal bleeding and their impact on portal pressure [PP] and survival: 73 patients were included after recovery from the 1[st] attack of variceal bleeding. They were randomly assigned into nadolol group [G1] [n=18], sclerotherapy group [G2] [N=18], combined nadolol and sclerotherapy group [G3] [n=20] and placebo group G4 [n=17]. Portal pressure was significantly reduced in G1 and G3 [P<0.01], and significantly increased in G2 [P<0.05], with insignificant change in G4. Hepatic dysfunction insignificantly affected PP response to different modalities. Significantly less percentage of rebleeders under different therapeutic modalities were encountered after one year from initiation of therapy when compared to placebo. Patients with critical initial PP [15-30 ml saline] showed a significantly lower percentage of rebleeders compared to those with serious initial PP [>30 ml saline], in G1, G2 and G3 [P<0.05]. Larger varices showed higher percentage of rebleeding among the studied groups. As regards one year survival, insignificant difference was observed among the studied group [G1 93.75%, G2 88.88%, G3 88.88%, G4 68.75%]. The combination of nadolol and sclerotherapy made varices to be eradicated by a significantly less number of sessions of sclerotherapy [P<0.01], and an insignificantly lower volume of ethanolamine per session. We concluded that variceal rebleeding can be more or less similarly prevented by nadolol, sclerotherapy or both with the advantage of earlier variceal eradication and better control of PP when nadolol is added to sclerotherapy. The degree of hepatic dysfunction dose not affect PP response to the applied therapeutic modality. Risk of rebleeding is positively affected by pre-treatment PP and variceal size. Survival is insignificantly improved by the applied therapeutic modalities

Hepatic glycogen depletion in fed female rats induced by piroxicam

Se estudiaron en ratas hembras alimentadas normalmente los efectos de la administración intraperitoneal de piroxicam sobre los nivels hepáticos de glucógeno y la actividad de enzimas claves involucradas en el metabolismo de dicho homopolisacárido. El contenido de glucógeno en hígado disminuyó proporcionalmente al tiempo de tratamiento y a la dosis de piroxicam administrado. Dicho efecto persistió vários días después de suspender la administración de piroxicam. La administración de nadolol o de fenobarbital resultó ineficaz para prevenir el efecto depletorio provocado por piroxicam. En las ratas tratadas, la actividad de glucosa-6-fosfatasa, glucógeno fosforilasa y glucógeno sintetasa no cambió respecto a los controles. Tampoco se modificó significativamente la proporción de glucógeno fosforilasa en la forma activa (a), como consecuencia de sucesivas dosis diarias de piroxicam. En cambio, fue demostrada una reducción en la forma activa (I) de la glucógeno sintetasa. Esta reducción fue dependiente del tiempo de tratamiento con piroxicam. Además, la sobrecarga con glucosa resultó ineficiente para restabelecer la actividad del la glucógeno sintetasa y la síntesis de glucógeno en los animales tratados con piroxican. El efecto producido por piroxican sobre el metabolismo de glucógeno plantea la posibilidad de que el hígado llegue a resultar incapaz de mantener la homeostasis de la glucosa. Asimismo, la disminución en los niveles de glucógeno podría ocasionar un bloqueo en el metabolismo de drogas que fueren administradas conjuntamente con piroxicam, ya que la biotransformación de los xenobióticos es un proceso dependiente de las reservas de dicho polisacárido en las células hepáticas

Un caso de enfermedad de peyronie asociado con uso de betabloqueantes / One case of peyronie disease associated with use of betabloquer

Se describe un caso de Enfermedad de Peyronie en un paciente hipertenso tratado en forma crónica con nadolol (betabloqueante). Se establece la asociación hoy descrita entre esta enfermedad y este tipo de drogas, señalandose que este efecto secundario, aunque raro, debe tomarse en cuenta en pacientes hipertensos que reciben betabloqueantes