Diferenças entre Duas Condições Cardíacas Hipertróficas Distintas: Doença de Fabry Versus Cardiomiopatia Hipertrófica / Differences Between Two Distinct Hypertrophic Cardiac Conditions: Fabry Disease versus Hypertrophic Cardiomyopathy

Resumo Fundamento A cardiomiopatia hipertrófica (CMH) e a doença de Fabry (DF) são doenças herdadas geneticamente com características fenotípicas de hipertrofia ventricular esquerda (HVE) que causam resultados cardíacos adversos. Objetivos Investigar as diferenças demográficas, clínicas, bioquímicas, eletrocardiográficas (ECG) e ecocardiográficas (ECO) entre CMH e DF. Métodos 60 pacientes com CMH e 40 pacientes com DF foram analisados retrospectivamente como uma subanálise do "estudo LVH-TR" após exclusão de pacientes com fibrilação atrial, ritmo de estimulação, bloqueios de ramo e bloqueios atrioventriculares (AV) de segundo e terceiro graus. O nível de significância foi aceito como <0,05. Resultados O sexo masculino (p=0,048) e a creatinina (p=0,010) são significativamente maiores a favor da DF; entretanto, infradesnivelamento do segmento ST (p=0,028), duração do QT (p=0,041), espessura do septo interventricular (SIVd) (p=0,003), espessura da parede posterior (PWd) (p=0,009), insuficiência mitral moderada a grave (IM) (p=0,013) e o índice de massa ventricular esquerda (IMVE) (p=0,041) são significativamente maiores a favor da CMH nas análises univariadas. Na análise multivariada, a significância estatística apenas permanece na creatinina (p=0,018) e na duração do intervalo QT (0,045). A DF foi positivamente correlacionada com a creatinina (rho=0,287, p=0,004) e a CMH foi positivamente correlacionada com o PWd (rho=0,306, p=0,002), IVSd (rho=0,395, p<0,001), IM moderada-grave (rho= 0,276, p<0,005), IMVE (rho=0,300, p=0,002), espessura relativa da parede (ERP) (rho=0,271, p=0,006), duração do QT (rho=0,213, p=0,034) e depressão do segmento ST (rho =0,222, p=0,026). Conclusão Características bioquímicas, ECG e ECO específicas podem auxiliar na diferenciação e no diagnóstico precoce da CMH e da DF.

Abstract Background Hypertrophic cardiomyopathy (HCM) and Fabry disease (FD) are genetically inherited diseases with left ventricular hypertrophy (LVH) phenotype characteristics that cause adverse cardiac outcomes. Objectives To investigate the demographic, clinical, biochemical, electrocardiographic (ECG), and echocardiographic (ECHO) differences between HCM and FD. Methods 60 HCM and 40 FD patients were analyzed retrospectively as a subanalysis of the 'LVH-TR study' after excluding patients with atrial fibrillation, pace rhythm, bundle branch blocks, and second and third-degree atrioventricular (AV) blocks. The significance level was accepted as <0.05. Results Male gender (p=0.048) and creatinine (p=0.010) are significantly higher in favor of FD; however, ST depression (p=0.028), QT duration (p=0.041), interventricular septum thickness (IVSd) (p=0.003), posterior wall thickness (PWd) (p=0.009), moderate-severe mitral regurgitation (MR) (p=0.013), and LV mass index (LVMI) (p=0.041) are significantly higher in favor of HCM in the univariate analyses. In multivariate analysis, statistical significance only continues in creatinine (p=0.018) and QT duration (0.045). FD was positively correlated with creatinine (rho=0.287, p=0.004) and HCM was positively correlated with PWd (rho=0.306, p=0.002), IVSd (rho=0.395, p<0.001), moderate-severe MR (rho=0.276, p<0.005), LVMI (rho=0.300, p=0.002), relative wall thickness (RWT) (rho=0.271, p=0.006), QT duration (rho=0.213, p=0.034) and ST depression (rho=0.222, p=0.026). Conclusion Specific biochemical, ECG, and ECHO characteristics can aid in the differentiation and early diagnosis of HCM and FD.

Infección por dengue sin signos de alarma en un niño con cardiopatía chagásica crónica

Se presenta el caso de un preescolar en que se diagnosticó una cardiomiopatía chagásica crónica posterior a una infección aguda por virus dengue. El niño, residente de un área endémica para enfermedad de Chagas, debutó con insuficiencia cardíaca que mejoró con el tratamiento de soporte y tras la resolución completa de la arbovirosis, persistieron los cambios de cardiomiopatía crónica. Esta evidencia de alteración estructural miocárdica se atribuyó a la cardiomiopatía chagásica de base previamente subclínica. La coexistencia de enfermedades infecciosas en el trópico representa un reto diagnóstico, situación a la que se agregan problemas socioeconómicos como la pobreza y falta de acceso a servicios sanitarios básicos.

A case is reported of a chronic chagasic cardiomyopathy in a two-years old child who was diagnosed after an acute dengue virus infection. The patient residing in an endemic area for Chagas disease, debuted with heart failure that improved with support treatment and after the complete resolution of the arbovirus, the changes of chronic cardiomyopathy persisted. The myocardial structural alteration was attributed to subclinical chagasic cardiomyopathy. The coexistence of infectious diseases in the tropics represents a diagnostic challenge, a situation to which are added problems such as poverty and lack of access to basic health services.

Mecanismos y dianas terapéuticas del inflamasoma NLRP3 en la miocardiopatía diabética / NLRP3 inflammasome mechanism and therapeutic targets in diabetic cardiomyopathy

Resumen La cardiomiopatía diabética es una complicación grave de la diabetes causada por estrés oxidativo, inflamación, resistencia a la insulina, fibrosis miocárdica y lipotoxicidad. Se trata de un padecimiento insidioso, complejo y difícil de tratar. El inflamasoma NLRP3 desencadena la maduración y liberación de citoquinas proinflamatorias, participa en procesos fisiopatológicos como la resistencia a la insulina y la fibrosis miocárdica, además de estar estrechamente relacionado con la aparición y progresión de la cardiomiopatía diabética. El desarrollo de inhibidores dirigidos a aspectos específicos de la inflamación sugiere que el inflamasoma NLRP3 puede utilizarse para tratar la cardiomiopatía diabética. Este artículo pretende resumir el mecanismo y las dianas terapéuticas del inflamasoma NLRP3 en la cardiomiopatía diabética, así como aportar nuevas sugerencias para el tratamiento de esta enfermedad.

Abstract Diabetic cardiomyopathy (DCM) is a serious complication of diabetes caused by oxidative stress, inflammation, insulin resistance, myocardial fibrosis, and lipotoxicity; its nature is insidious, complex and difficult to treat. NLRP3 inflammasome triggers the maturation and release of pro-inflammatory cytokines, participates in pathophysiological processes such as insulin resistance and myocardial fibrosis, in addition to being closely related to the development and progression of diabetic cardiomyopathy. The development of inhibitors targeting specific aspects of inflammation suggests that NLRP3 inflammasome can be used to treat diabetic cardiomyopathy. This paper aims to summarize NLRP3 inflammasome mechanism and therapeutic targets in diabetic cardiomyopathy, and to provide new suggestions for the treatment of this disease.

Síndrome de tako-tsubo en una adolescente. Presentación de caso

El síndrome de tako-tsubo es una miocardiopatía aguda por estrés, caracterizada por una anormalidad regional del movimiento de la pared del ventrículo izquierdo, con un patrón circunferencial peculiar que resulta en un abultamiento notorio del ventrículo izquierdo durante la sístole. En Cuba, el síndrome de tako-tsubo ha sido publicado en pacientes adultos, pero se considera una entidad rara en niños, razón por la cual se decidió hacer este reporte. Se presenta el caso de una adolescente de 16 años, con antecedentes de haber dado a luz hacía 44 días al momento del ingreso, que fue recibida en el Servicio de Emergencias en estado grave, con disnea, dolor precordial y manifestaciones de choque, por lo que fue derivada inmediatamente a la Unidad de Cuidados Intensivos Pediátricos. Los antecedentes de haber tenido un factor desencadenante de estrés como el parto por cesárea, el electrocardiograma con signos de isquemia miocárdica y el ecocardiograma típico, con discinesia de segmentos apicales del ventrículo izquierdo, permitieron hacer el diagnóstico de síndrome de tako-tsubo y dirigir el tratamiento en ese sentido. Este síndrome es infrecuente en la edad pediátrica, por tanto, puede presentarse como una forma grave y no ser reconocido, trayendo implicaciones pronósticas.

Takotsubo syndrome is an acute stress cardiomyopathy, characterized by a regional abnormality of left ventricular wall motion, with a peculiar circumferential pattern that results in marked left ventricular bulging during systole. In Cuba, takotsubo syndrome has been published in adult patients, but it is considered a rare entity in children, so it was decided to make this report. The case of a 16-years-old adolescent, with a history of having given birth 44 days before at the time of admission, who was received at the Emergency Department in serious condition, with dyspnea, precordial pain, and manifestations of shock, for what she was immediately referred to the Pediatric Intensive Care Unit it is presented. The history of having had a stress trigger such as delivery by cesarean section, the electrocardiogram with signs of myocardial ischemia, and the typical echocardiogram, with dyskinesia of the apical segments of the left ventricle, allowed the diagnosis of takotsubo syndrome and direct treatment in that sense. This syndrome is rare in the pediatric age, therefore, it can present as a severe form and not be recognized, bringing prognostic implications.

Como eu faço no Coração de Atleta: avaliação dos diferentes tipos de adaptação ao exercício / My approach to "Athlete'S Heart": evaluation of the different types of adaptation to exercise

A prática regular de esportes pode induzir adaptações no coração, sendo essa condição comumente chamada de "coração de atleta". As alterações observadas incluem dilatação das câmaras cardíacas, aumento da espessura miocárdica, melhora do enchimento ventricular, aumento da trabeculação do ventrículo esquerdo (VE), dilatação da veia cava inferior, entre outras. Essas alterações também podem ser observadas em algumas doenças cardíacas, como cardiomiopatia (CMP) dilatada, hipertrófica e outras. Dessa forma, os exames de imagem cardíaca são fundamentais na identificação dessas alterações e na diferenciação entre o "coração de atleta" e uma possível cardiopatia.(AU)

Exercise-induced adaptation may occur in amateur and professional athletes. This condition is commonly named "athlete's heart". The alterations observed include dilation of the heart chambers, increased myocardial thickness, improved ventricular filling, increased left ventricular trabeculation, dilation of the inferior vena cava, among others. These changes can also be observed in some heart diseases, such as dilated, hypertrophic and other cardiomyopathies (CMP). Thus, cardiac imaging tests are fundamental in identifying these alterations and in differentiating between "athlete's heart" and possible heart disease. (AU)

Estudio preliminar de correlación fenotipo-genotipo en miocardiopatías de pacientes derivados a un centro de alta complejidad del conurbano bonaerense / A Preliminary Study of the Phenotype-Genotype Correlation in Cardiomyopathies in Patients Referred to a Tertiary Healthcare Center in the Suburbs of Buenos Aires

RESUMEN Introducción : Las miocardiopatías se definen como un trastorno del miocardio en el que el músculo cardíaco es estructural y funcionalmente anormal, en ausencia de enfermedad arterial coronaria, hipertensión arterial (HTA), enfermedad valvular y enfermedad cardíaca congénita. Estas enfermedades son relativamente frecuentes, y suponen una importante causa de morbimortalidad a nivel global. Aunque el estudio genético se recomienda para el cribado familiar, la falta de datos robustos sobre asociaciones genotipo-fenotipo específicas ha reducido su impacto en el manejo clínico. Objetivos : El objetivo de este estudio es analizar la frecuencia de mutaciones en una población de pacientes con miocardiopatía derivados a un centro de alta complejidad y el análisis de la correlación genotipo-fenotipo en las mutaciones identificadas. Material y métodos: Se estudiaron en forma prospectiva 102 pacientes con sospecha de miocardiopatía hipertrófica (MCH) familiar, de los cuales 70 constituían casos índices, de una cohorte ambispectiva de pacientes con miocardiopatías controladas en un hos pital público de alta complejidad de tercer nivel de atención de la provincia de Buenos Aires, desde enero 2012 al 30 agosto 2022. Resultados : De 102 pacientes 83 fueron considerados afectados. De eelos, 31 eran MCH y 52 fenocopias, sin diferencia en el pronóstico. Se realizó estudio genético en 77 pacientes, de los cuales 57 presentaron mutaciones reconocibles, en el 80% de los casos coincidentes con un Score de Mayo ≥3. Se detectaron 28 variantes de significado incierto. Conclusiones : Se comprobó que realizar estudio molecular guiado por el Score de Mayo permitió obtener un alto grado de probabilidad de detectar mutaciones. Se evidenció la importancia del estudio molecular debido a la existencia de solapamiento fenotípico y genotípico de las miocardiopatías. El conocimiento de la variante genética causal actualmente no afecta el manejo clínico de la mayoría de los pacientes con MCH, pero es de ayuda ante un pequeño grupo de genes que tienen opciones de tratamiento.

ABSTRACT Background : Cardiomyopathies are defined as a disorder of the myocardium in which the heart muscle is structurally and functionally abnormal, in the absence of coronary artery disease, hypertension (HT), valvular heart disease and congenital heart disease. These diseases are relatively common and a major cause of morbidity and mortality worldwide. Although genetic testing is recommended for family screening, lack of solid data on specific genotype-phenotype associations has reduced its impact on clinical management. Objectives : This study aims to analyze the frequency of mutations in a population of patients with cardiomyopathy referred to a tertiary healthcare center and to analyze the genotype-phenotype correlation of the identified mutations. Methods : We prospectively included 102 patients with suspected familial hypertrophic cardiomyopathy (HCM), 70 of which were index cases, from an ambispective cohort of patients with cardiomyopathies treated in a tertiary healthcare public hos pital in the province of Buenos Aires, from January 2012 to August 30, 2022. Results : Of 102 patients, 83 were considered affected. Of these, 31 were HCM and 52 were phenocopies, with no difference in prognosis. A genetic study was carried out in 77 patients, of whom 57 presented recognizable mutations, in 80% of the cases coinciding with a Mayo Score ≥3. Twenty-eight variants of uncertain significance were detected. Conclusions : It was confirmed that molecular testing guided by the Mayo Score provided high probability of detecting mutations. Molecular testing proved to be important due to the phenotypic and genotypic overlap in cardiomyopathies. Understanding the causative genetic variant, nowadays, does not affect the clinical management of most HCM patients, but is helpful in a small group of genes with treatment options.

Efecto del alcohol sobre el corazón y el sistema cardiovascular: hipertrofia, remodelamiento y disminución del strain. Información actual / Alcohol Impact on the Heart and Cardiovascular System - Hypertrophy, Remodeling and Strain Impairment - Contemporary State-of-the-Art

RESUMEN Datos recientes muestran que el abuso crónico de alcohol puede conducir a disfunción cardiovascular, a partir de dosis de etanol tradicionalmente consideradas bajas, y que la aparición de arritmias, incluyendo la fibrilación auricular, aumenta aún en consumidores de alcohol moderados. Los otros mecanismos comunes del impacto negativo del etanol están relacionados con el desarrollo de hipertensión y su consecuencia directa, la hipertrofia, fibrosis y disfunción diastólica. Debido a que la probabilidad de reversibilidad del remodelamiento cardíaco depende de un diagnóstico temprano de disfunción cardíaca, se debería recomendar la aplicación más amplia de métodos nuevos y más sensibles de evaluación de la función miocárdica, incluyendo el strain longitudinal ventricular izquierdo y derecho, así como de los protocolos adaptados a la ecocardiografía de estrés.

ABSTRACT The recent data show that chronic overuse of alcohol may lead to cardiovascular dysfunction, starting from traditionally judged as low ethanol doses, and that the burden of arrhythmias, including atrial fibrillation, increases even in moderate alcohol consumers. The other common mechanisms of the disadvantageous impact of ethanol are related to the development of hypertension and its direct aftermath, hypertrophy, fibrosis, and diastolic dysfunction. Since the chance of the reversibility of cardiac remodeling depends on the early diagnosis of cardiac dysfunction, the wider application of novel and sensitive methods of myocardial function assessment, including longitudinal strain of the left and right ventricles, as well as the adapted protocols for stress echocardiography, should be recommended.

Evaluación de resultados en una serie de pacientes con trasplante cardiaco: experiencia en el Instituto Nacional de Cardiología

Exponemos la experiencia del Instituto Nacional de Cardiología de una serie de casos de pacientes sometidos a trasplante cardiaco entre mayo de 2016 y junio 2022. Se realizaron 14 trasplantes, 13 fueron del sexo masculino. La edad osciló entre 19 y 62 años. Las etiologías fueron cardiopatías de tipo idiopática en 57% y valvular en 21%. El 50% se trasplantó en INTERMACS 4 (Interagency Registry for Mechanically Assisted Circulatory Support), 21% INTERMACS 3 y solo 28% en INTERMACS 2. Tres pacientes se trasplantaron con asistencia circulatoria tipo membrana circulación extracorpórea. Las complicaciones más frecuentes fueron las infecciosas. La mortalidad hospitalaria fue 35,7%. Hubo un fallecido en el seguimiento tras 5 años de trasplante.

We present the experience of the National Institute of Cardiology of a series of cases of patients undergoing heart transplantation between May 2016 and June 2022. Fourteen transplants were performed, 13 of the patients were male. The age ranged between 19 and 62 years. The etiologies were idiopathic heart disease in 57% and valvular heart disease in 21%. Fifty percent was transplanted in INTERMACS 4 (Interagency Registry for Mechanically Assisted Circulatory Support), 21% in INTERMACS 3 and only 28% in INTERMACS 2. Three patients were transplanted with membrane type extracorporeal circulation circulatory support. The most frequent complications were infectious. Hospital mortality was 35.7%. There was one patient who died during follow-up after 5 years of transplantation.

Desafios e Aplicações dos Testes Genéticos na Cardiomiopatia Dilatada: Genótipo, Fenótipo e Implicações Clínicas / Challenges and Applications of Genetic Testing in Dilated Cardiomyopathy: Genotype, Phenotype and Clinical Implications

Resumo Os testes genéticos para cardiomiopatia dilatada (CMD) apresentam uma positividade de até 40%, mas há uma grande heterogeneidade genética e outros desafios decorrentes de expressividade variável e penetrância incompleta. O heredograma é fundamental para diferenciar os casos de CMD esporádica e familiar, por meio da avaliação do histórico familiar. A CMD familiar apresenta um rendimento maior nos testes genéticos, mas a CMD esporádica não exclui a possibilidade de causa genética. Alguns genes têm fenótipos específicos, sendo o gene da Lamina ( LMNA ) o mais fortemente associado a um fenótipo de arritmias malignas e quadros de insuficiência cardíaca (IC) avançada. A presença de uma variante genética causal também pode ajudar na avaliação prognóstica, identificando quadros mais graves e com menores taxas de remodelamento reverso em comparação com indivíduos com genótipo negativo. As diretrizes atuais recomendam a avaliação e aconselhamento genético em indivíduos com CMD, além do rastreamento em cascata nos familiares de primeiro grau nos casos em que há uma ou mais variantes identificadas, sendo uma oportunidade para o diagnóstico e tratamento precoces. Familiares com genótipo positivo e fenótipo negativo são candidatos à avaliação seriada, com periodicidade que varia conforme a idade. O genótipo também auxilia na indicação individualizada de cardiodesfibrilador implantável e em recomendações quanto à atividade física e planejamento familiar. Estudos em curso esclarecem progressivamente os detalhes das relações genótipo/fenótipo de um grande número de variantes e fazem com que a genética molecular esteja cada vez mais presente na prática clínica.

Abstract Genetic tests for dilated cardiomyopathy (DCM) have a diagnostic yield of up to 40%, but there is significant genetic heterogeneity and other challenges, such as variable expressivity and incomplete penetrance. Pedigree analysis is essential for distinguishing between sporadic and familial DCM cases by assessing family history. Familial DCM yields higher results in genetic testing, but sporadic DCM does not rule out the possibility of a genetic cause. Some genes have specific phenotypes, with the Lamin gene ( LMNA ) being associated with a phenotype of malignant arrhythmias and advanced heart failure (HF). The presence of a causal genetic variant can also aid in prognostic evaluation, identifying more severe cases with lower rates of reverse remodeling (RR) compared to individuals with a negative genotype. Current guidelines recommend genetic evaluation and counseling for individuals with DCM, along with cascade screening in first-degree relatives in cases where one or more variants are identified, offering an opportunity for early diagnosis and treatment. Relatives with a positive genotype and negative phenotype are candidates for serial evaluation, with frequency varying by age. Genotype also assists in individualized recommendations for implantable cardioverter-defibrillator (ICD) placement and advice regarding physical activity and family planning. Ongoing studies are progressively elucidating the details of genotype/phenotype relationships for a large number of variants, making molecular genetics increasingly integrated into clinical practice.

Coumel tachycardia in children / Taquicardia de Coumel en niños

Abstract Background: Coumel tachycardia is an infrequent form of supraventricular tachycardia (SVT) that usually occurs in infants and children. It is a tachycardia mediated by an accessory pathway with retrograde slow conduction that explains the classic ECG pattern with long RP' interval and negative P waves in leads II, III, and aVF. In this study, we describe the clinical course and management of Coumel tachycardia in children. Case report: We conducted a retrospective review of five consecutive pediatric patients, mean age 11 ± 3 years (range 6 to 14). The first episode of SVT was at a mean age of 10.4 ± 4.8 years (range 2 to 14) with a mean evolution of 7.4 ± 9.4 months (range 1 to 24). Pharmacological therapy was unsuccessful despite the combination of antiarrhythmic drugs. The tachycardia was incessant with a density > 85% by 24-hour Holter monitoring; one patient developed tachycardia-induced cardiomyopathy. All children underwent successful radiofrequency catheter ablation, mean 5 ± 3 applications (range 1 to 8) with a single session and with no complications. After a mean follow-up of 24 ± 16 months, all patients were asymptomatic and recurrence-free without antiarrhythmic treatment. Conclusions: Coumel tachycardia is clinically persistent and usually refractory to antiarrhythmic treatment with substantial risk of tachycardia-mediated cardiomyopathy. Catheter ablation is effective and safe in children; thus, it should be indicated promptly and based on individual selection.

Resumen Introducción: La taquicardia de Coumel es una forma poco frecuente de taquicardia supraventricular que suele presentarse en lactantes. Es una taquicardia mediada por una vía accesoria de conducción lenta retrógrada que explica el patrón ECG clásico con intervalo RP' largo y ondas P negativas en las derivaciones II, III y aVF. En este trabajo se describe el curso clínico y el manejo de la taquicardia de Coumel en niños. Caso clínico: Se llevó a cabo una revisión retrospectiva de cinco pacientes pediátricos consecutivos, con una media de edad de 11 ± 3 años (intervalos 6 a 14). El primer episodio de taquicardia 10.4 ± 4.8 años con evolución de 7.4 ± 9.4 meses. El tratamiento farmacológico fue ineficaz a pesar de la combinación de antiarrítmicos. La taquicardia era incesante con una densidad > 85% por Holter-24h; un paciente desarrolló miocardiopatía inducida por taquicardia. Todos los niños fueron sometidos a ablación con catéter y radiofrecuencia con éxito, y un promedio de 5 ± 3 aplicaciones en una sola sesión y sin complicaciones. Después de un seguimiento de 24 ± 16 meses, todos los pacientes fueron asintomáticos y libres de recurrencia sin tratamiento antiarrítmico. Conclusiones: La taquicardia de Coumel es clínicamente persistente y generalmente refractaria al tratamiento antiarrítmico con un riesgo sustancial de miocardiopatía mediada por taquicardia. La ablación con catéter es eficaz y segura en niños, por lo que debe indicarse de forma temprana y en lactantes de una selección individual.

Avaliação Prognóstica da Microalternância da onda T na Cardiomiopatia Hipertrófica em um Seguimento Clínico de 9 anos / Prognostic Evaluation of Microvolt T-Wave Alternans in Hypertrophic Cardiomyopathy: 9-year Clinical Follow-up

Resumo Fundamento: A morte súbita cardíaca (MSC), decorrente de arritmias ventriculares, é a principal complicação da cardiomiopatia hipertrófica (CMH). A microalternância da onda T (MAOT) está associada à ocorrência de arritmias ventriculares em diversas cardiopatias, mas seu papel na CMH permanece incerto. Objetivo: Avaliar associação da MAOT com a ocorrência de MSC ou arritmias ventriculares malignas em pacientes com CMH. Método: Pacientes com diagnóstico de CMH e classe funcional I-II (NYHA) foram selecionados de forma consecutiva. No início do seguimento os participantes realizaram a avaliação da MAOT pela metodologia da média móvel modificada no teste de esforço. Os resultados foram classificados em alterado ou normal. O desfecho foi composto por MSC, fibrilação ventricular, taquicardia ventricular sustentada (TVS) e terapia apropriada do cardioversor desfibrilador implantável (CDI). O nível de significância estatística foi de 5%. Resultados: Um total de 132 pacientes (idade média de 39,5±12,6 anos) foram incluídos, com tempo de seguimento médio de 9,5 anos. A MAOT foi alterada em 74 (56%) participantes e normal em 58 (44%). Durante o seguimento, nove (6,8%) desfechos ocorreram, com prevalência de 1,0%/ano, sendo seis casos de MSC, dois choques apropriados do CDI e um episódio de TVS. MAOT alterada foi associada à taquicardia ventricular não sustentada no Holter (p=0,016), espessura septal≥30 mm (p<0,001) e resposta inadequada da pressão arterial ao esforço (p=0,046). Cinco pacientes (7%) e quatro pacientes (7%) com MAOT alterada e normal, respectivamente, apresentaram desfecho primário [OR=0,85(IC95%: 0,21-3,35, p=0,83)]. Curvas de eventos de Kaplan-Meir não apresentaram diferenças entre MAOT normal e alterada. Conclusão: A MAOT alterada não foi associada à ocorrência de MSC ou arritmias ventriculares potencialmente fatais em pacientes com CMH, e a baixa taxa desses eventos em um seguimento em longo prazo sugere o bom prognóstico dessa cardiopatia.

Abstract Background: Sudden cardiac death (SCD) resulting from ventricular arrhythmia is the main complication of hypertrophic cardiomyopathy (HCM). Microvolt T-wave alternans (MTWA) is associated with the occurrence of ventricular arrhythmias in several heart diseases, but its role in HCM remains uncertain. Objective: To evaluate the association of MTWA with the occurrence of SCD or potentially fatal ventricular arrhythmias in HCM patients in a long-term follow-up. Methods: Patients diagnosed with HCM and NYHA functional class I-II were consecutively selected. At the beginning of the follow-up, the participants performed the MTWA evaluation using the modified moving average during the stress test. The results were classified as altered or normal. The composite endpoint of SCD, ventricular fibrillation, sustained ventricular tachycardia (SVT) or appropriate implantable cardiac defibrillation (ICD) therapy was assessed. The level of significance was set at 5%. Results: A total of 132 patients (mean age of 39.5 ± 12.6 years) were recruited and followed for a mean of 9.5 years. The MTWA test was altered in 74 (56%) participants and normal in 58 (44%). Nine events (6.8%) occurred during the follow-up, with a prevalence of 1.0%/year - six SCDs, two appropriate ICD shocks and one episode of (SVT). Altered MTWA was associated with non-sustained ventricular tachycardia on Holter (p = 0.016), septal thickness ≥30 mm (p < 0.001) and inadequate blood pressure response to effort (p = 0.046). Five patients with altered MTWA (7%) and four patients with normal MTWA (7%) had the primary outcome [OR = 0.85 (95% CI: 0.21 - 3.35, p=0.83)]. Kaplan-Meir event curves showed no differences between normal and altered MTWA. Conclusion: Altered MTWA was not associated with the occurrence of SCD or potentially fatal ventricular arrhythmias in HCM patients, and the low rate of these events during long-term follow-up suggests the good prognosis of this heart disease.

Recurrent takotsubo syndrome: case report and literature review

Introduction: Takotsubo syndrome is a cardiomyopathy that can lead to severe myocardial involvement. It is characterized by the presence of signs and symptoms suggestive of ventricular dysfunction associated with an adrenergic discharge during a stressful event. This case report presents a literature review, as well as a comparison with other similar cases. Case presentation. A 56-year-old female with a previous episode of Takotsubo was admitted to the emergency department due to symptoms of acute coronary syndrome and a history of Takotsubo syndrome. Her electrocardiogram showed T-wave inversion in leads V1-V4 and a raise in troponins. Percutaneous coronary angiography revealed no coronary lesions, and an echocardiogram revealed segmental alterations compatible with Takotsubo syndrome, requiring medical therapy with beta-blockers and angiotensin-converting enzyme (ACE) inhibitors, with subsequent improvement in ventricular function. Conclusions. Recurrence in Takotsubo cardiomyopathy is a rare complication that should be suspected. The risk factors associated with recurrence are not known. Although therapy with ACE inhibitors and beta-blockers seems to have an impact on the recovery of ventricular function in patients with this condition, further studies are necessary to establish the best pharmacological treatment.

Introducción. La miocardiopatía de Takotsubo (MT) es una afección cardiaca que puede generar compromiso miocárdico severo y se caracteriza por la presencia de signos y síntomas sugestivos de disfunción ventricular que se asocian a una descarga adrenérgica durante un evento estresor. En este reporte de caso se realizó una revisión de la literatura y se hizo una comparación con otros casos similares al presentado. Presentación del caso. Mujer de 56 años, quien asistió al servicio de urgencias por síntomas sugestivos de un síndrome coronario agudo. A la paciente, que tenía antecedente de MT, se le realizó un electrocardiograma que mostró inversión de la onda T en las derivaciones V1-V4 y elevación de troponinas, una angiografía coronaria que evidenció arterias epicárdicas sin lesiones y un ecocardiograma que reveló alteraciones segmentarias compatibles con MT, por lo que se estableció manejo con betabloqueadores e inhibidores de la enzima convertidora de angiotensina (IECA), con lo cual se logró mejoría de la función ventricular. Conclusiones. La MT es una afección poco frecuente de la cual no se conocen los factores de riesgo asociados a su recurrencia. Aunque la terapia con IECA y betabloqueadores parece tener un impacto en la recuperación de la función ventricular en pacientes con esta condición, se requieren estudios adicionales para establecer el mejor manejo farmacológico.