Tireotoxicose induzida pela amiodarona - revisão de literatura e atualização clínica / Amiodarone-induced thyrotoxicosis - literature review & clinical update

Resumo A amiodarona é amplamente utilizada no tratamento de arritmias atriais e ventriculares, porém devido sua alta concentração de iodo, o uso crônico da droga pode induzir distúrbios tireoidianos. A tireotoxicose induzida pela amiodarona (TIA) pode descompensar e exacerbar anormalidades cardíacas subjacentes, provocando aumento da morbidade e mortalidade, principalmente em pacientes com fração de ejeção do ventrículo esquerdo <30%. Os casos de TIA são classificados em dois subtipos que direcionam a conduta terapêutica. Os riscos e benefícios de manter a amiodarona devem ser avaliados de maneira individualizada, e a decisão de continuar ou suspender a droga deve ser tomada conjuntamente por cardiologistas e endocrinologistas. O tratamento de TIA tipo 1 é semelhante ao do hipertireoidismo espontâneo, sendo indicado o uso de drogas antitireoidianas (metimazol e propiltiouracil) em doses elevadas. A TIA tipo 1 mostra-se mais complicada, pois apresenta proporcionalmente maiores números de recorrências ou até mesmo a não remissão do quadro, sendo recomendado o tratamento definitivo (tireoidectomia total ou radioiodo). TIA tipo 2 é geralmente autolimitada, mas devido a elevada mortalidade associada a tireotoxicose em pacientes cardiopatas, o tratamento deve ser instituído para que o eutireoidismo seja atingido mais rapidamente. Em casos bem definidos de TIA tipo 2, o tratamento com corticosteroides é mais efetivo do que o tratamento com drogas antitireoidianas. Em casos graves, independentemente do subtipo, a restauração imediata do eutiroidismo por meio da tireoidectomia total deve ser considerada antes que o paciente evolua com piora clínica excessiva, pois a demora na indicação da cirurgia está associada ao aumento da mortalidade.

Abstract Amiodarone is widely used in treating atrial and ventricular arrhythmias; however, due to its high iodine concentration, the chronic use of the drug can induce thyroid disorders. Amiodarone-induced thyrotoxicosis (AIT) can decompensate and exacerbate underlying cardiac abnormalities, leading to increased morbidity and mortality, especially in patients with left ventricular ejection fraction <30%. AIT cases are classified into two subtypes that guide therapeutic management. The risks and benefits of maintaining the amiodarone must be evaluated individually, and the therapeutic decision should be taken jointly by cardiologists and endocrinologists. Type 1 AIT treatment is similar to that of spontaneous hyperthyroidism, using antithyroid drugs (methimazole and propylthiouracil) at high doses. Type 1 AIT is more complicated since it has proportionally higher recurrences or even non-remission, and definitive treatment is recommended (total thyroidectomy or radioiodine). Type 2 AIT is generally self-limited, yet due to the high mortality associated with thyrotoxicosis in cardiac patients, the treatment should be implemented for faster achievement of euthyroidism. Furthermore, in well-defined cases of type 2 AIT, the treatment with corticosteroids is more effective than treatment with antithyroid drugs. In severe cases, regardless of subtype, immediate restoration of euthyroidism through total thyroidectomy should be considered before the patient progresses to excessive clinical deterioration, as delayed surgery indication is associated with increased mortality.

Toxicidad pulmonar aguda por amiodarona con dosis baja de impregnación: reporte de caso / Acute amiodarone pulmonary toxicity with low impregnation dose: case report

Se sabe que la amiodarona, un potente antiarrítmico, causa toxicidad pulmonar. La neumonitis intersticial crónica es la presentación más común. Sin embargo, la toxicidad pulmonar aguda es rara y provoca una mayor mortalidad. Se presenta un paciente de 61 años con fibrilación auricular persistente que, tras tratamiento por un mes con amiodarona vía oral a dosis baja de impregnación de 400 miligramos al día, desarrolló toxicidad pulmonar aguda secundaria al antiarrítmico confirmada por radiografía y tomografía. Su caso tuvo resolución después de la suspensión del fármaco y tratamiento con esteroides.

Amiodarone, considered a potent antiarrhythmic, is known to cause pulmonary toxicity. Chronic interstitial pneumonitis is the most common presentation. However, acute pulmonary toxicity is rare and has a higher case fatality rate. We present a 61-year-old patient with persistent atrial fibrillation who, after a one-month treatment with oral amiodarone at a low dose impregnation of 400 mg/day, develops acute pulmonary toxicity, with radiographic and tomographic resolution after antiarrhythmic suspension and steroid treatment.

Hyponatremia in elderly patients with fragility fractures of the proximal femur: a cross-sectional study / Hiponatremia em pacientes idosos com fratura proximal de fêmur por fragilidade: um estudo transversal

ABSTRACT Introduction: Proximal femur fractures affect the mortality and morbidity of elderly individuals. Recent studies have shown an association between fragility fractures and hyponatremia, a common fluid and electrolyte balance disorder. Objectives: This study aimed to investigate the occurrence of hyponatremia in patients with fragility fractures of the proximal femur. Methods: The authors looked into the data from the medical records of patients admitted to the emergency unit of the Real Hospital Português for fragility fractures of the proximal femur from 2014 to 2017. The study included patients with serum sodium levels recorded in their charts. Results: Fourteen of 69 (20.3%) patients with proximal femur fractures had hyponatremia. The main factors linked to hyponatremia were lung disease, and prescription of amiodarone and/or antidepressants. Conclusion: In elderly individuals, fragility fractures of the proximal femur may correlate with hyponatremia, particularly among patients on amiodarone or antidepressants.

RESUMO Introdução: Fratura de fêmur proximal tem impacto na mortalidade e morbidade de idosos. Estudos recentes vêm demonstrando associação entre fratura por fragilidade e hiponatremia, um distúrbio hidroeletrolítico comum na prática médica. Objetivos: Investigar a ocorrência de hiponatremia em pacientes com fratura proximal de fêmur por fragilidade. Metodologia: Foram coletados dados a partir de prontuários de pacientes admitidos na emergência do Real Hospital Português devido à fratura proximal de fêmur por fragilidade, entre 2014 e 2017, e aqueles com natremia disponível no prontuário eletrônico foram incluídos no estudo. Resultado: Dentre os 69 pacientes com fratura de fêmur proximal, houve uma ocorrência de 14 pacientes com hiponatremia, o que corresponde a 20,3%. Os principais fatores associados à hiponatremia no estudo foram doença pulmonar, uso de amiodarona e antidepressivos. Conclusão: Em idosos, a fratura de fêmur proximal por fragilidade pode estar correlacionada com hiponatremia, principalmente quando estão sob uso de amiodarona ou antidepressivos.

Tratamiento de la embarazada con fibrilación auricular y compromiso hemodinámico / Treatment of pregnant women with atrial fibrillation and hemodynamic disorders

Las arritmias cardiacas son complicaciones frecuentes en el embarazo, son más frecuentes las supraventriculares, con gran importancia la fibrilación auricular con compromiso hemodinámico, que pone en peligro al binomio madre hijo, asociado al efecto dañino de los medicamentos antiarrítmicos. El autor se propone analizar los elementos del consenso científico al tratar la fibrilación auricular de forma más adecuada para el binomio madre hijo, así como la protocolización del tratamiento. A partir de la experiencia del tratamiento de dos embarazadas con fibrilación auricular, con formas y desenlaces totalmente diferentes, en discusión del colectivo multidisciplinario, se busca y analiza una protocolización actualizada, en la conducta a seguir con madre hijo, en caso de arritmia. Las arritmias en la embarazada representan un riesgo para eventos fetales adversos, además de los riesgos potenciales de los medicamentos usados para el tratamiento. La cardioversión eléctrica, sincronizada, parece ser claramente idónea en el tratamiento(AU)

Cardiac arrhythmias are frequent complications in pregnancy, supra ventricular diseases are more frequent, with great importance atrial fibrillation with hemodynamic disorders, which puts the child mother binomial in danger, associated with the harmful effect of antiarrhythmic drugs. The author proposes to analyze the elements of the scientific consensus when treating atrial fibrillation in a more adequate way for the child mother binomial, as well as the protocolization of the treatment. From the experience of the treatment of two pregnant women with atrial fibrillation, with completely different forms and outcomes, in discussion of the multidisciplinary group, an updated protocol is searched and analyzed, in the behavior to be followed with the mother, in case of arrhythmia. Arrhythmias in the pregnant woman represent a risk for adverse fetal events, in addition to the potential risks of the medications used for the treatment. The synchronized electrical cardioversion seems to be clearly suitable in the treatment(AU)

Comparación de la eficacia y seguridad de flecainida y dronedarona como terapias antiarrítmicas para mantenimiento de ritmo sinusal en fibrilación auricular / Comparison of the efficacy and safety of dronedarone and flecainide as maintenance antiarrhythmic therapy for sinus rhythm in atrial fibrillation

Resumen Introducción y objetivos: Dronedarona y flecainida son antiarrítmicos de primera elección para reducir recurrencias de fibrilación auricular (FA), sin existir estudios que los comparen entre sí. Nuestro objetivo es comparar la eficacia en cuanto a prevención de recurrencias y seguridad de ambos fármacos. Métodos: Estudio retrospectivo en el que se incluyeron 123 pacientes de forma consecutiva en tratamiento con flecainida o dronedarona desde octubre de 2010 hasta febrero de 2013 por FA paroxística (76.4%) y FA persistente (23.6%). Se realizó cardioversión eléctrica en un 7.3% de los pacientes y farmacológica en un 16.3%. La mediana (rango intercuartílico) de seguimiento fue de 301 días (92-474), con una media de 2.8 revisiones por paciente. Se realizó análisis de tiempo hasta el primer evento mediante Kaplan-Meier y regresión de Cox ajustada por un índice de propensión. Resultados: De entre los 123 sujetos incluidos con FA, 71 fueron tratados con flecainida y 52 con dronedarona. Durante el seguimiento se registraron 36 recurrencias y 20 efectos adversos. Se documentaron un 36.6% de recurrencias en los pacientes tratados con flecainida en comparación con un 21% en los tratados con dronedarona (p = 0.073). En el análisis multivariante, dronedarona se mostró al menos tan eficaz como flecainida para prevenir recurrencias de FA (HR: 0.53, IC 95%: 0.20-1.44, p = 0.221) y demostró un perfil de seguridad comparable al de flecainida (HR: 0.68, IC 95%: 0.18-2.53, p = 0.566). Conclusiones: Según nuestra experiencia, dronedarona resulta al menos tan eficaz como flecainida para el mantenimiento de ritmo sinusal, con un buen perfil de tolerabilidad, a pesar de pautarse en pacientes con un perfil clínico más desfavorable.

Abstract Introduction and objectives: Dronedarone and flecainide are the first pharmacological choice to reduce recurrence of atrial fibrillation (AF); however, there are no studies comparing them. A study was performed to compare the efficacy in terms of recurrence of AF and safety of both drugs. Methods: A retrospective cohort study was conducted that included 123 consecutive patients treated with flecainide or dronedarone due to paroxysmal AF (76.4%) or persistent AF (23.6%), from October 2010 to February 2013. Electrical cardioversion was performed in 7.3% of patients and pharmacological cardioversion in 16.3%. The median (interquartile range) follow-up was 301 days (92-474) with a mean of 2.8 reviews per patient. Time to first event analysis was performed using Kaplan-Meier and Cox regression, adjusted for propensity score. Results: Of the 123 consecutive patients with AF included, 71 were on dronedarone and 52 on flecainide. During the follow-up, there were 36 AF recurrences and 20 safety events. There were recurrences in 36.6% of patients treated with flecainide, compared with 21% of those receiving dronedarone (P = .073). Dronedarone showed to be at least as effective as flecainide in preven- ting recurrence of atrial fibrillation (HR: 0.53, 95% CI: 0.20-1.44, P = .221), and demonstrated an acceptable safety profile when compared with flecainide (HR: 0.68, 95% CI: 0.18-2.53, P = .566). Conclusions: In our experience, dronedarone has been at least as effective and safe as flecainide, despite it was most frequently prescribed in patients with worse baseline risk profile.

The role of under-investigated connexins in musculoskeletal tissue: a brief review with emphasis on bone tissue / El papel de las escasamente investigadas conexinas en el tejido músculo-esquelético: una breve revisión con énfasis en el tejido óseo

Connexins (Cxs) are a family of transmembrane proteins that form gap junctions and hemi-channels, which mediate cell-cell communication between neighboring cells and the respective extracellular milieu in different tissues. Most tissues and cell types throughout the body express one or more Cx proteins, highlighting its importance in regulating cell growth, differentiation, adhesion, migration, cell death and others. Moreover, Cx can propagate intracellular signals through its C-terminus domain, and thus function beyond a mere channel. Cx43 is the most highly expressed and most well studied Cx in bone and musculoskeletal tissues, although Cx40, Cx45, Cx46 and more recently, the Cx37 have been described in bone tissue, along with Cx26, Cx32 and Cx39 in other musculoskeletal tissues. Here, we discuss the basic structure of gap junctions and the role of the Cxs in musculoskeletal tissue, with special focus on Cx37. (AU)

Las conexinas (Cxs) son una familia de proteínas transmembrana que forman uniones en hendidura y hemicanales encargados de mediar la comunicación entre células vecinas y el respectivo medio extracelular en diferentes tejidos. La mayoría de los tejidos y células expresan una o más proteínas conexina, jugando un papel importante en la regulación de la proliferación celular, diferenciación, adhesión, migración y muerte celular, entre otras funciones. Además de actuar como un canal, las conexinas pueden propagar señales intracelulares a través del dominio C-terminal. La Cx43 es la conexina mas expresada y mejor estudiada en el tejido óseo y el músculo, aunque las Cx40, Cx45, Cx46, y mas recientemente Cx37, son también detectadas en el hueso. A su vez la expresión de la Cx26, Cx32 y Cx39 ha sido observada en otros tejidos músculoesqueléticos. En este manuscrito describimos la estructura básica de las uniones tipo gap y el papel que las Cxs, y en especial la Cx37, tienen en tejidos músculo-esqueléticos. (AU)

Intra-Articular Pigmentation of Synovium: An Unusual Cause

An unusual grayish brown discoloration of the synovium was found during a knee arthroscopy of a 72-year-old man. He also had similar pigmentation affecting the skin on the legs, arms, hands, and face. It was found he had been taking 400 mg of amiodarone hydrochloride daily for last 7 years. Amiodarone is known to cause a slate grey pigmentation of skin and cornea, but we believe this is the first report of amiodarone-induced pigmentation of the synovium. The arthroscopist should be aware of the possibility of drug-related synovial pigmentation and include this in differential diagnosis.

Prevalencia de potenciales interacciones farmacológicas de Azitromicina en Colombia, 2012-2013 / Prevalence of potential drug interactions with azithromycin in Colombia, 2012-2013

Objetivos Determinar la prevalencia de potenciales interacciones farmacológicas entre azitromicina y diferentes antiarrítmicos del grupo IA y III en una base de datos de prescripción de medicamentos a nivel nacional durante el año 2012-2013. Métodos Estudio retrospectivo a partir de una base de datos poblacional de dispensación de medicamentos. Se extrajeron datos de los pacientes que recibieron azitromicina desde 1 de enero de 2012 a 30 junio de 2013, al igual que pacientes que recibieron este antibiótico en combinación a otros medicamentos con demostrado riesgo de provocar arritmias cardíacas al usarse concomitantemente. Se establecieron frecuencias y proporciones. Resultados Se identificaron 13 859 pacientes que recibieron azitromicina sola o en combinación con otros medicamentos. El tiempo promedio de uso fue 4,5±0,9 días; Un total de 702 pacientes (5,1 %) recibieron azitromicina más otros 19 fármacos de potencial riesgo. Los más frecuentemente asociados fueron: loratadina (77,1 %), difenhidramina (16,5 %) y amitriptilina (8,1 %). Las combinaciones con un solo medicamento fueron las más frecuentes (n=533, 75,9 %), con predominio de azitromicina+loratadina. El máximo número de fármacos combinados fue seis (n=2, 0,3 %). Conclusiones La identificación mediante bases de datos poblacionales la prescripción de medicamentos, es una manera eficaz de encontrar potenciales interacciones entre estos. La frecuencia de potenciales interacciones entre azitromicina y otros fármacos es común en pacientes colombianos. Se debe estimar el riesgo de ocurrencia de eventos cardiacos adversos.(AU)

Objective To determine the prevalence of potential drug interactions between azithromycin and different IA and III antiarrhythmic groups in a national database of drug prescriptions in 2012-2013. Methods Retrospective study based on a population database of medicine dispensation. Data from patients who received azithromycin between January 1, 2012 and June 30, 2013 were extracted along with data from patients who received azithromycin in combination with other medications shown to cause heart arrhythmias when used concomitantly. Frequencies and proportions were established. Results 13 859 patients receiving azithromycin alone or in combination with other drugs were identified. The average time of use was 4.5 ± 0.9 days. A total of 702 patients (5.1 %) received azithromycin plus 19 other potentially risky drugs. The most frequently associated were loratadine (77.1 %), diphenhydramine (16.5 %) and amitriptyline (8.1 %). Combinations with a single drug were the most frequent (n=533, 75.9 %), predominantly azithromycin+loratadine. The maximum number of combined drugs was six (n=2, 0.3 %). Conclusions Identification of drug prescriptions through population databases is an effective way to find potential drug interactions. The frequency of potential interactions between azithromycin and other drugs is common in Colombian patients. Future research should assess the risk of occurrence of adverse cardiac events.(AU)

Hepatic computed tomography changes caused by amiodarone

No abstract available.

Eventos cardíacos decorrentes da infusão contínua de cloridrato de amiodarona: implicações para o enfermeiro / Cardiac events originated from the continuous infusion of amiodarone hydrochloride: consequences for the nurse

O objeto de estudo são os eventos cardíacos resultantes da infusão contínua de cloridrato de amiodarona em pacientes que evoluíram com fibrilação atrial em pós-operatório de cirurgia cardíaca. Os objetivos foram descrever as características dos pacientes que receberam infusão contínua de cloridrato de amidoarona, apresentar a prevalência de bradicardia e hipotensão encontrada nos pacientes que receberam infusão contínua de cloridrato de amiodarona e discutir as implicações dos achados para a prática dos enfermeiros a partir da prevalência encontrada de bradicardia e hipotensão decorrente da infusão contínua desta substância. Trata-se de um estudo transversal, retrospectivo, documental, por meio de análise de prontuários e avaliação quantitativa dos mesmos. Desenvolvida em uma unidade de pós-operatório de cirurgia cardíaca em um hospital universitário pertencente à rede sentinela no município do Rio de Janeiro. Foi considerado hipotensão em presença de PAS menor que 90 mmHg e bradicardia em presença de frequência cardíaca menor que 60 bpm. As variáveis que caracterizavam a população do estudo e as aferições de pressão arterial e frequência cardíaca foram transcritas para um instrumento de coleta de dados dos anos de 2010 e 2011, gerando 1782 horas de infusão contínua de cloridrato de amiodarona em 27 pacientes cirúrgicos (10,50%). Tratou-se de uma população predominantemente feminina, com idade a cima de 60 anos, período de internação superior a uma semana, apresentava hipertensão arterial prévia (59,26%), era portadora de fibrilação atrial (55,56%) e o diagnóstico cirúrgico de revascularização do miocárdio com circulação extracorpórea foi predominante (70,37%). Os dados mostram que 85,19% dos pacientes eram portadores de pelo menos um fator de risco, 70,37% apresentavam dois fatores de risco e 55,55% apresentavam três fatores de risco para desenvolver fibrilação atrial no pós-operatório de cirurgia cardíaca...

The subject-matter of the following study is the cardiac events that are consequences from the continuous infusion of amiodarone hydrochloride into patients that developed atrial fibrillation in a postoperative care from a cardiac surgery. The aims of the study are: to describe the characteristics of the patients that received continuous infusion of amiodarone hydrochloride; to present the prevalence of bradycardia and hypotension in the patients that received continuous infusion of amiodarone hydrochloride; and to discuss the implications of the findings for the practice of nurses from the prevalence of bradycardia and hypotension that stemmed from the continuous infusion of amiodarone hydrochloride. This is a cross-sectional, retrospective, documentary study through the analysis and quantitative evaluation of medical records. It was developed in a cardiac surgery postoperative unit in a university hospital that belongs to the Rede Sentinela in the City of Rio de Janeiro. Hypotension was defined as the presence of a systemic arterial blood pressure (ABP) lower than 90 mmHg and bradycardia as the presence of a heart rate below 60 bpm. The variables that characterized the population of the study and the measuring of arterial blood pressure and heart rate were transcribed into a data collection instrument through the years 2010 and 2011, creating 1782 hours of continuous infusion of amiodarone hydrochloride into 27 surgical patients (10,50%). The population of the study was mainly composed of women over 60 years old, with an admission over a week period, they showed pre-existing arterial hypertension (58,26%) and have atrial fibrillation (55,56%) and the surgical diagnosis of myocardium revascularization with extracorporeal circulation was predominant (70,37%)...

The diagnostic utility of chest computed tomography scoring for the assessment of amiodarone-induced pulmonary toxicity

BACKGROUND/AIMS: Amiodarone is one of the most widely used antiarrhythmic agents; however, amiodarone-induced pulmonary toxicity (APT) can be irreversible and sometimes fatal. The aim of this study was to evaluate the feasibility of chest computed tomography (CT) as a diagnostic tool for APT and to assess the utility of the CT APT score as an index for predicting the severity of APT. METHODS: Patients underwent amiodarone treatment for various reasons, most often atrial fibrillation, for more than 2 years, and those that received a cumulative dose > 100 g were enrolled. A total of 34 patients who underwent chest CT between December 2011 and June 2012 were enrolled, whether or not they had clinical symptoms. The APT CT score was defined as the number of involved regions in the lung, which was divided into 18 regions (right and left, upper, middle, and lower, and central, middle, and peripheral). The CT findings were evaluated according to the total dose and duration of amiodarone treatment and the results of a pulmonary function test. Clinical symptoms and outcomes were also evaluated according to APT CT scores. RESULTS: Seven patients had positive APT CT scores (interstitial fibrosis in five, organizing pneumonia in one, and mixed interstitial fibrosis and organizing pneumonia in one), and these patients exhibited significantly lower diffusion capacity for carbon monoxide in the lungs compared with patients without an increased APT CT score (70.2% +/- 6.9% vs. 89.7% +/- 19.4%; p = 0.011). Three of the seven patients experienced overt APT that required hospital admission. CONCLUSIONS: Chest CT is a useful diagnostic tool for APT, and the APT CT score might be a useful index for assessing the severity of APT.

Adverse effects of long-term amiodarone therapy

No abstract available.

Disfunção tiróidea e amiodarona / Thyroid dysfunction and amiodarone

Apesar de a maioria dos doentes tratados com amiodarona permanecer em eutiroidia, alguns desenvolvem hipertiroidismo (HPEIA) ou hipotiroidismo (HPOIA) induzidos pela amiodarona. Os autores apresentam uma análise retrospectiva dos processos de dez doentes com disfunção tiróidea induzida pela amiodarona. Verificou-se que seis doentes eram mulheres e que o tempo médio de toma da amiodarona foi de 17,7 meses. O HPOIA foi o mais frequente (seis doentes). Dos doentes com HPEIA, dois tinham HPEIA tipo 2, um tipo 1 e um tipo 3. Sintomas sugestivos de disfunção tiróidea ocorreram em cinco doentes, a maioria com HPOIA. No HPEIA, a clínica mais comum foi exacerbação da arritmia de base (três doentes). A interrupção da amiodarona e administração de levotiroxina foi a terapêutica escolhida em 83,3% dos casos de HPOIA, enquanto a tionamida associada a corticoide com suspensão da amiodarona foi opção em 75% dos casos de HPEIA. Registraram-se três óbitos, todos com HPEIA. O HPEIA constituiu uma complicação potencialmente fatal. A clínica pode ser vaga, pelo que a monitorização da função tiróidea é obrigatória.

Although most patients remain clinically euthyroid, some develop amiodarone-induced hyperthyroidism (HPEAI) or hypothyroidism (HPOAI). The authors present a retrospective analysis of ten patients with amiodarone-induced thyroid dysfunction. Six patients were female and mean amiodarone intake was 17.7 months. HPOIA was more common (six patients). From all the patients with HPEAI, two had type 2, one had type 1, and one had type 3 hyperthyroidism. Symptoms suggestive of thyroid dysfunction occurred in five patients, most of them with HPOAI. In HPEAI, the most frequent symptom was exacerbation of arrhythmia (three patients). Discontinuation of amiodarone and treatment with levothyroxine was chosen in 83.3% of the HPOAI cases, while thyonamide treatment with corticosteroids and without amiodarone was the option in 75% of the HPEAI cases. There were three deaths, all in patients with HPEAI. HPEAI is potentially fatal. The clinical picture may be vague, so the thyroid monitoring is mandatory.

Importance of 99mTc-sestaMIBI thyroid scan in a case of amiodarone-induced thyrotoxicosis / A importância da cintigrafia tiroidea com 99mTc-sestaMIBI num caso de tireotoxicose induzida pela amiodarona

Amiodarone (AM)-induced thyrotoxicosis (AIT) is a condition with uncertainties from the diagnostic and therapeutic standpoints. A 54-year old male was referred to the hospital due to thyrotoxicosis. He had history of atrial fibrillation medicated with AM. No history of pre-existing thyroid disease was present, thyroid palpation revealed no goiter, and there were no signs of Graves' ophthalmopathy. Thyroid autoantibodies and thyroid-stimulating hormone receptor antibodies (TRABs) were negative. Thyroid and Doppler ultrasounds were normal. 99mTc-sestaMIBI thyroid scan (STS) showed uptake with rapid washout. AM therapy was discontinued, and combined therapy was started. After a long course of glucocorticoid and thionamides, the patient became euthyroid. It is necessary to distinguish between the types of AIT to decide whether or not continue AM treatment; after that, the appropriate therapy should be selected. STS was very important in the diagnosis of the type of AIT.

A tireotoxicose induzida por amiodarona (AIT) é uma condição incerta do ponto de vista de diagnóstico e tratamento. Um homem de 54 anos de idade foi encaminhado ao hospital devido à tireotoxicose. Ele apresentou um histórico de fibrilação atrial medicada com amiodarona (AM). Não havia histórico de doença da tiroide preexistente, a palpação da tiroide não revelou bócio e não havia sinais de oftalmopatia de Graves. Os autoanticorpos contra a tireoide e anticorpos para os receptores de hormônio estimulante da tireoide (TRABs) foram negativos. Os resultados do ultrassom da tiroide e do exame de Doppler foram normais. A cintigrafia da tiroide com 99mTc-sestaMIBI mostrou captação com rápida eliminação. O tratamento com AM foi descontinuado, e se iniciou a terapia combinada. Após um longo tratamento com glicocorticoides e tionaminas, o paciente se tornou eutiroide. É necessário distinguir entre os tipos de AIT para se determinar a continuação ou interrupção do tratamento com AM. Depois disso, o tratamento apropriado deve ser selecionado. A STS é muito importante no diagnóstico do tipo de AIT.

Arritmias en el embarazo / Arrhythmias during pregnancy

Las arritmias durante el embarazo son eventos de aparición frecuente. Desde las extrasístoles aisladas hasta las taquiarritmias, capaces de poner en riesgo las vidas materna y fetal, constituyen el amplio espectro de presentación. Muchas de ellas exigen intervenciones de urgencia, tratamientos crónicos o ambos. La comunicación de este caso nos motivó a realizar una revisión de las indicaciones y posibilidades farmacológicas de las taquicardias paroxísticas supraventriculares en este período particular de la mujer. El fármaco de elección para el manejo agudo de las taquicardias paroxísticas supraventriculares es la adenosina. Este agente debería encontrarse siempre en el área de quirófano al alcance de los anestesiólogos, para un manejo terapéutico de urgencia. La conducta obstétrica estará marcada por el estado hemodinámico de la madre y del feto.

Arrhythmias during pregnancy are frequent events. There is a wide spectrum of presentations: from isolated extrasystoles to tachyarrhythmias with risk to mother and fetal life. Many of these arrhythmias need urgent interventions and/or chronic treatment. The communication of this clinical case motivated us to realize a review of the indications and pharmacological possibilities in paroxysmal tachyarrhythmias in this particular period in women. Adrenosine is the pharmacological treatment of choice to manage paroxysmal supraventricular tachyarrhythmias. This drug should always be at hand in the operating theater, to be used by the anesthesiologists for the therapeutic managing of the emergencies. Obstetric clinical conduct will depend on the haemodynamic condition of the mother and the fetus.

As arritmias durante a gravidez são eventos de ocorrência freqüente. Desde as extrassístoles isoladas até as taquiarritmias, que podem pôr em risco as vidas materna e fetal, constituem o amplo espectro de apresentação. Muitas delas exigem intervenções de urgência, tratamentos crônicos ou ambos. Este caso nos estimulou a fazer uma revisão das indicações e possibilidades farmacológicas das taquicardias paroxísticas supraventriculares nesse período da mulher. O fármaco de escolha para o manejo agudo das taquicardias paroxísticas supraventriculares é a adenosina. Este agente deveria estar sempre disponível na sala de operações, ao alcance da mão dos anestesiologistas, para um manejo terapêutico de urgência. A conduta obstétrica estará marcada pelo estado hemodinâmico da mãe e do feto.

Amiodarona e tireotoxicose: relatos de casos / Amiodarone and thyrotoxicosis: case reports / Amiodarona y tirotoxicosis: relatos de casos

Relata-se que a disfunção tireoidiana induzida pela amiodarona afeta de 2 a 24 por cento dos usuários. Embora seja fácil tratar o hipotireoidismo induzido pela amiodarona, o desenvolvimento da tireotoxicose leva a uma abordagem difícil na maioria dos casos. O objetivo deste estudo é descrever três casos diferentes de pacientes com tireotoxicose induzida por amiodarona e discutir os aspectos clínicos e laboratoriais, e as diferentes abordagens para esses casos. É essencial avaliar cuidadosamente os pacientes antes e durante o tratamento com amiodarona, tendo em vista que o diagnóstico e o tratamento imediato dessa condição são cruciais em pacientes com alto risco cardiovascular.

Amiodarone-induced thyroid dysfunction has been reported to affect 2-24 percent of users. Despite the easy management of amiodarone-induced hypothyroidism, the development of thyrotoxicosis leads to a difficult approach in most cases. The aim of this study is to describe three different cases of patients with amiodarone-induced thyrotoxicosis and discuss the clinical and laboratorial aspects, and the different approaches to them. It is essential to carefully evaluate patients before and during amiodarone therapy, since the prompt diagnosis and treatment of this condition is essential in patients with high cardiovascular risk.

Se relata que la disfunción tiroidea inducida por la amiodarona afecta de 2 a 24 por ciento de los usuarios. Aunque sea fácil tratar el hipotiroidismo inducido por la amiodarona, el desarrollo de la tirotoxicosis lleva a un abordaje difícil en la mayoría de los casos. El objetivo de este estudio es describir tres casos diferentes de pacientes con tirotoxicosis inducida por amiodarona y discutir los aspectos clínicos y de laboratorio, y los diferentes abordajes para esos casos. Es esencial evaluar cuidadosamente los pacientes antes y durante el tratamiento con amiodarona, teniendo en vista que el diagnóstico y el tratamiento inmediato de esa condición son cruciales en pacientes con alto riesgo cardiovascular.