RESUMO
BACKGROUND: There are no randomized studies comparing the maintenance of sinus rhythm after catheter ablation (CA) concerning treatment with antiarrhythmic drugs (AA) in elderly patients with paroxysmal atrial fibrillation (AF). OBJECTIVES: To compare the clinical results of pulmonary vein (PV) isolation with the second-generation PVAC Gold catheter against AA treatment in elderly people with recurrent symptomatic paroxysmal AF, refractory to at least one AA, and without structural heart disease. METHODS: Sixty patients with paroxysmal AF ≥ 65 years old were randomized to two forms of treatment: group 1: CA and group 2: AA drugs. The primary outcome was the AF recurrence-free rate after at least one year of follow-up. Secondary outcomes were: progression to persistent forms of AF, impact on quality of life (QOLF), and complications. The significance level adopted in the statistical analysis was 5% (p<0.05). RESULTS: The AF recurrence-free rate was 80% (10% with amiodarone) in the CA group, after 1.3 procedures per patient and 65% in the AA group (60% with amiodarone), (p = 0.119) in an average follow-up of 719 days (Q1: 566; Q3: 730). The persistent AF free rate was 83.4% in the AC group and 67.7% in the AA group (p = 0.073) Both strategies showed an improvement in the AFQoL score during follow-up (p < 0.001), with no difference between the groups. Although without clinical repercussions or impact on the intellectual assessment test, 25% of patients in the CA group showed signs of cerebral embolization on brain MRI. CONCLUSIONS: Both strategies for maintaining sinus rhythm promoted an improvement in the quality of life of elderly patients with symptomatic AF, with no statistical difference in the clinical outcomes. Additional studies using technologies with a better safety profile are needed to evaluate the benefits of CA in elderly patients with AF.
FUNDAMENTO: Não existem estudos randomizados comparando a manutenção do ritmo sinusal após ablação por cateter (AC) em relação ao tratamento com fármacos antiarrítmicos (AA) em pacientes idosos portadores fibrilação atrial (FA) paroxística. OBJETIVOS: Comparar os resultados clínicos do isolamento das veias pulmonares (VPs) com o cateter PVAC Gold de segunda geração com o uso de AA em idosos com FA paroxística sintomática, recorrente, apesar do uso de fármacos AA. MÉTODOS: Sessenta pacientes com FA paroxística ≥ 65 anos e sem cardiopatias estruturais foram randomizados para duas formas de tratamento: grupo 1: AC e grupo 2: AA. O desfecho primário foi a taxa livre de recorrência de FA após pelo menos um ano de seguimento. Os desfechos secundários foram: progressão para formas persistentes de FA, impacto na qualidade de vida (QVFA) e complicações. O nível de significância adotado na análise estatística foi de 5% (p<0,05). RESULTADOS: A taxa livre de recorrência de FA foi de 80% (10% com amiodarona) no grupo AC, após 1,3 procedimentos por paciente e de 65% no grupo AA (60% com amiodarona), (p = 0,119) num seguimento médio de 719 dias (Q1: 566; Q3: 730). A taxa livre de FA persistente foi de 83,4% no grupo AC e de 67,7% no grupo AA (p = 0,073). Ambas as estratégias apresentaram melhora no escore de QVFA durante o seguimento (p < 0,001), sem diferença entre os grupos. Embora sem repercussão clínica ou impacto no teste de avaliação intelectual, 25% dos pacientes do grupo PVAC apresentou sinais de embolização cerebral na RNM cerebral. CONCLUSÕES: Ambas as estratégias para manutenção do ritmo sinusal promoveram melhora na qualidade de vida de pacientes idosos com FA sintomática, sem diferença estatística nos desfechos clínicos preconizados. Estudos adicionais usando tecnologias com melhor perfil de segurança são necessários para avaliar os benefícios da AC em pacientes idosos com FA.
Assuntos
Antiarrítmicos , Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Qualidade de Vida , Humanos , Fibrilação Atrial/cirurgia , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/terapia , Fibrilação Atrial/fisiopatologia , Antiarrítmicos/uso terapêutico , Feminino , Masculino , Idoso , Ablação por Cateter/métodos , Resultado do Tratamento , Veias Pulmonares/cirurgia , Recidiva , Amiodarona/uso terapêutico , Fatores de TempoRESUMO
The chemical structure of piperidine has a unique ability to combine with other molecular fragments. This fact makes it possible to actively use it as an effective basis for the creation of new drug-like substances. Thus, the aim of the current investigation was to study the acute toxicity, local anesthetic potency, and antiarrhythmic activity of the two new synthesized piperidine derivatives under laboratory codes LAS-286 and LAS-294 (local anesthetic substances). The Bulbring & Wajda animal model and method of determining the nociception threshold during electrical stimulation was used to investigate the action of the substance during infiltration anesthesia. An antiarrhythmic activity was observed by the aconitine-induced rat arrhythmia model. Additionally, these compounds were studied in relation to molecular docking to delineate the structure-activity relationships. The tested piperidine derivatives had a low toxicity in the subcutaneous and intravenous administration routes. The experimental results showed a higher prolonged and pronounced local anesthetic activity for LAS-286 at a 0.5% concentration, compared to the reference preparations. The low dosage of 0.1 mg/kg of LAS-294 demonstrated a pronounced preventive antiarrhythmic effect in 90% of cases on the development of mixed arrhythmia, caused by aconitine. The results of molecular docking confirmed a higher binding affinity of the tested piperidines with the Nav1.4 and Nav1.5 macromolecules. The results of the present study are very promising, because these piperidines have shown a high biological activity, which can suggest a potential therapeutic application in the future.
Assuntos
Anestésicos Locais , Antiarrítmicos , Simulação de Acoplamento Molecular , Piperidinas , Animais , Antiarrítmicos/farmacologia , Anestésicos Locais/farmacologia , Piperidinas/farmacologia , Piperidinas/química , Ratos , Masculino , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/tratamento farmacológico , Relação Estrutura-Atividade , Ratos Wistar , Modelos Animais de DoençasRESUMO
The difficulty in swallowing is a frequent problem when oral solid dosage forms (conventional tablets or capsules) are administered to paediatric population or patients with dysphagia. An interesting alternative to overcome these problems are non-conventional formulations like chewable gels, commonly known as 'gummies'. Therefore, this work addresses the design, development and characterization of gummies using gelatine and pectin, for the vehiculization of the antiarrhythmic amiodarone (AMIO). Applying a Design of Experiments (DoE) approach, four gelatine (GG1-GG4) and eight pectin formulations (PG1-PG8) were developed. Considering the obtained results for responses during DoE evaluation (i.e., volume, syneresis, hardness, and gumminess), GG3 and PG8 were selected for complete characterization. Water activity, pH, drug content, texture parameters (adhesiveness, springiness, cohesiveness, and fracturability), disintegration time, in vitro dissolution, and microbiological features were evaluated. The obtained results were within the expected values for this type of formulation. The dissolution profiles showed a 94 % - 99 % of the AMIO content released for GG3 and PG8, respectively, so they could be considered suitable as immediate release dosage forms. In conclusion, the chewable gels were successfully developed and characterised, suggesting a potential means to accomplish a final prototype for the improvement of congenital cardiopathies treatment.
Assuntos
Amiodarona , Antiarrítmicos , Géis , Cardiopatias Congênitas , Pectinas , Amiodarona/administração & dosagem , Amiodarona/química , Humanos , Pectinas/química , Antiarrítmicos/administração & dosagem , Antiarrítmicos/química , Cardiopatias Congênitas/tratamento farmacológico , Gelatina/química , Animais , Criança , Administração Oral , Liberação Controlada de Fármacos , Composição de Medicamentos/métodos , Solubilidade , Química Farmacêutica/métodosRESUMO
INTRODUCTION: Inappropriate sinus tachycardia (IST) is a common condition with frequently not tolerated beta-blockers or ivabradine and a high rate of complication in ablation strategy; we describe an alternative anatomical approach of sinus node (SN) modulation. METHODS: This retrospective study describes a case series of 6 patients from two centers diagnosed with symptomatic IST undergoing SN ablation. RESULTS: The mean age was 40.6 ± 13.9 years; five of the six patients were female, 100% of patients reported heart palpitations, and 66% reported dizziness, the average heart rate (HR) on a 24-h Holter was 93.2 ± 7.9 bpm. HR during the first stage of a stress test using a standard Bruce protocol was 150 ± 70 bpm, The average HR on 24-h Holter postablation was 75 ± 5.6 bpm, the sinus rate HR during stage 1 of a Bruce protocol exercise stress test was 120 ± 10 bpm. CONCLUSION: This is the first case series reporting the acute and long-term results of a novel anatomical approach for SN modulation to treat IST targeting the arcuate ridge (AR) under intracardiac echography (ICE) guidance. The novel anatomic ICE-guided catheter ablation approach aimed to identify the earliest activation at the AR with an extension of RF lesions toward its septal region seems effective and safe to modulate the SN in symptomatic patients with IST refractory to medical treatment.
Assuntos
Ablação por Cateter , Frequência Cardíaca , Taquicardia Sinusal , Humanos , Feminino , Taquicardia Sinusal/cirurgia , Taquicardia Sinusal/fisiopatologia , Estudos Retrospectivos , Masculino , Pessoa de Meia-Idade , Adulto , Resultado do Tratamento , Potenciais de Ação , Valor Preditivo dos Testes , Antiarrítmicos/uso terapêutico , Fatores de Tempo , Ultrassonografia de Intervenção , Eletrocardiografia Ambulatorial , Resistência a Medicamentos , Nó Sinoatrial/cirurgia , Nó Sinoatrial/fisiopatologia , EcocardiografiaAssuntos
Benzazepinas , Ivabradina , Ivabradina/uso terapêutico , Ivabradina/farmacologia , Humanos , Benzazepinas/uso terapêutico , Benzazepinas/farmacologia , Arritmias Cardíacas/tratamento farmacológico , Antiarrítmicos/uso terapêutico , Antiarrítmicos/farmacologia , Taquicardia Ventricular/tratamento farmacológicoRESUMO
BACKGROUND: The benefit of catheter ablation for atrial fibrillation (AF) in patients with heart failure with preserved ejection fraction (HFpEF) remains uncertain. OBJECTIVE: We performed a systematic review and meta-analysis to compare catheter ablation and medical therapy (antiarrhythmics for rhythm or rate control) in patients with AF and HFpEF. METHODS: We searched PubMed, Embase, and Cochrane Central Register of Controlled Trials. Outcomes were the composite end points of death or heart failure (HF) hospitalization, all-cause death, cardiovascular death, all-cause rehospitalization, and HF hospitalization. Statistical analysis was performed using R statistical software, version 4.3.2 (R Foundation for Statistical Computing). Heterogeneity was assessed with I2 statistics. RESULTS: We included 20,257 patients from 8 studies. Of those, 3 were derived from RCTs, either through post hoc analysis or subgroup analysis, and 5 were observational studies. The median follow-up ranged from 24.6 to 61.2 months. Compared with medical therapy, catheter ablation was associated with a statistically significant lower risk of death or HF hospitalization (hazard ratio [HR] 0.62; 95% confidence interval [CI] 0.47-0.83; P = .001; I2 = 66%), all-cause death (HR 0.68; 95% CI 0.46-0.99; P = .047; I2 = 61%), cardiovascular death (HR 0.42; 95% CI 0.21-0.84; P = .014; I2 = 22%), and HF hospitalization (HR 0.43; 95% CI 0.23-0.82; P = .011; I2 = 87%). CONCLUSION: In this meta-analysis, catheter ablation was associated with a lower risk of all-cause death, cardiovascular death, HF hospitalization, and all-cause rehospitalization in comparison to medical therapy in patients with AF and HFpEF.
Assuntos
Fibrilação Atrial , Ablação por Cateter , Insuficiência Cardíaca , Volume Sistólico , Humanos , Antiarrítmicos/administração & dosagem , Fibrilação Atrial/complicações , Fibrilação Atrial/mortalidade , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Fibrilação Atrial/terapia , Ablação por Cateter/métodos , Ablação por Cateter/estatística & dados numéricos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Volume Sistólico/efeitos dos fármacos , Volume Sistólico/fisiologiaRESUMO
BACKGROUND: Amiodarone (AMIO) is an antiarrhythmic drug with the pKa in the physiological range. Here, we explored how mild extracellular pH (pHe) changes shape the interaction of AMIO with atrial tissue and impact its pharmacological properties in the classical model of sea anemone sodium channel neurotoxin type 2 (ATX) induced late sodium current (INa-Late) and arrhythmias. METHOD: Isolated atrial cardiomyocytes from male Wistar rats and human embryonic kidney cells expressing SCN5A Na+ channels were used for patch-clamp experiments. Isolated right atria (RA) and left atria (LA) tissue were used for bath organ experiments. RESULTS: A more acidophilic pHe caused negative inotropic effects on isolated RA and LA atrial tissue, without modification of the pharmacological properties of AMIO. A pHe of 7.0 changed the sodium current (INa) related components of the action potential (AP), which was enhanced in the presence of AMIO. ATXinduced arrhythmias in isolated RA and LA. Also, ATX prolonged the AP duration and enhanced repolarization dispersion in isolated cardiomyocytes in both pHe 7.4 and pHe 7.0. Pre-incubation of the isolated RA and LA and isolated atrial cardiomyocytes with AMIO prevented arrhythmias induced by ATX only at a pHe of 7.0. Moreover, AMIO was able to block INa-Late induced by ATX only at a pHe of 7.0. CONCLUSION: The pharmacological properties of AMIO concerning healthy rat atrial tissue are not dependent on pHe. However, the prevention of arrhythmias induced by INa-Late is pHe-dependent. The development of drugs analogous to AMIO with charge stabilization may help to create more effective drugs to treat arrhythmias related to the INa-Late.
Assuntos
Potenciais de Ação , Amiodarona , Antiarrítmicos , Arritmias Cardíacas , Átrios do Coração , Miócitos Cardíacos , Ratos Wistar , Animais , Amiodarona/farmacologia , Antiarrítmicos/farmacologia , Masculino , Humanos , Ratos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Potenciais de Ação/efeitos dos fármacos , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Concentração de Íons de Hidrogênio , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/induzido quimicamente , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Células HEK293 , Sódio/metabolismo , Técnicas de Patch-Clamp , Venenos de Cnidários/farmacologiaRESUMO
BACKGROUND: Atrial fibrillation (AF) and heart failure (HF) frequently coexist, resulting in adverse outcomes. However, controversies remain regarding the efficacy of catheter ablation (CA) in AF patients with severe left ventricular dysfunction. OBJECTIVES: The purpose of this study was to perform a meta-analysis of prospective randomized controlled trials to evaluate the efficacy of CA versus medical therapy (MT) in AF patients with left ventricular ejection fraction (LVEF) ≤45%. METHODS: We searched the literature for studies that compared CA to MT in AF patients with LVEF ≤45%. A meta-analysis of 7 clinical trials was performed, including 1163 patients with AF and HF. Subgroup analysis was performed based on baseline LVEF. All tests were 2-sided; only the p-value <0.05 was considered statistically significant. RESULTS: We found that CA was associated with lower all-cause mortality (risk ratio: 0.52, 95% CI: 0.37 to 0.72; p<0.01) and greater improvements in LVEF (mean difference: 4.80%, 95% CI: 2.29% to 7.31%; p<0.01) compared to MT. Patients in the CA group had a lower risk of HF hospitalization and AF recurrence and a significantly better quality of life than those in the MT group. The results of subgroup analysis indicated that patients with milder left ventricular dysfunction improved LVEF after AF ablation (mean difference: 6.53%, 95% CI: 6.18% to 6.88%; p<0.01) compared to patients with more severe disease (mean difference: 2.02%, 95% CI: 0.87% to 3.16%; p<0.01). CONCLUSIONS: Our meta-analysis demonstrated that CA was associated with significant improvements in outcomes of AF patients with LVEF ≤45%. Additionally, AF patients with milder left ventricular dysfunction could benefit more from CA.
FUNDAMENTO: A fibrilação atrial (FA) e a insuficiência cardíaca (IC) coexistem frequentemente, resultando em desfechos adversos. No entanto, permanecem controvérsias quanto à eficácia da ablação por cateter (AC) em pacientes com FA com disfunção ventricular esquerda grave. OBJETIVOS: O objetivo deste estudo foi realizar uma metanálise de ensaios prospectivos randomizados e controlados para avaliar a eficácia da AC versus terapia médica (TM) em pacientes com FA com fração de ejeção do ventrículo esquerdo (FEVE) ≤45%. MÉTODOS: Procuramos na literatura estudos que comparassem AC com TM em pacientes com FA com FEVE ≤45%. Foi realizada uma metanálise de 7 ensaios clínicos, incluindo 1.163 pacientes com FA e IC. A análise de subgrupo foi realizada com base na FEVE basal. Todos os testes foram bilaterais; apenas o valor p <0,05 foi considerado estatisticamente significativo. RESULTADOS: Descobrimos que a AC estava associada a menor mortalidade por todas as causas (taxa de risco: 0,52, IC 95%: 0,37 a 0,72; p<0,01) e maiores melhorias na FEVE (diferença média: 4,80%, IC 95%: 2,29% a 7,31%; p<0,01) em comparação com TM. Os pacientes do grupo AC apresentaram menor risco de hospitalização por IC e recorrência de FA e qualidade de vida significativamente melhor do que aqueles do grupo TM. Os resultados da análise de subgrupo indicaram que pacientes com disfunção ventricular esquerda mais leve melhoraram a FEVE após a ablação de FA (diferença média: 6,53%, IC 95%: 6,18% a 6,88%; p<0,01) em comparação com pacientes com doença mais grave (diferença média : 2,02%, IC 95%: 0,87% a 3,16%; p<0,01). CONCLUSÕES: Nossa metanálise demonstrou que a AC foi associada a melhorias significativas nos resultados de pacientes com FA com FEVE ≤45%. Além disso, pacientes com FA com disfunção ventricular esquerda mais leve poderiam se beneficiar mais com a AC.
Assuntos
Fibrilação Atrial , Ablação por Cateter , Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Fibrilação Atrial/cirurgia , Volume Sistólico , Função Ventricular Esquerda , Qualidade de Vida , Estudos Prospectivos , Resultado do Tratamento , Antiarrítmicos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Disfunção Ventricular Esquerda/etiologia , Ablação por Cateter/métodosRESUMO
INTRODUCTION: Amiodarone (AMD) is a clinically used drug to treat arrhythmias with significant effect upon the cardiac sodium channel Nav1.5. AMD has a pKa of 6.56, and changes in extracellular pH (pHe) may alter its pharmacological properties. Here we explored how changes in pHe impacts the pharmacological properties of AMD upon human-Nav1.5-sodium-current (INa) and in ex vivo rat hearts. METHODS: Embryonic-human-kidney-cells (HEK293) were used to transiently express the human alpha-subunit of NaV1.5 channels and the isolated heart of Wistar rats were used. Patch-Clamp technique was deployed to study INa and for electrocardiogram (ECG) evaluation the ex vivo heart preparation in the Langendorff system was applied. RESULTS: The potency of AMD upon peak INa was â¼25x higher in pHe 7.0 when compared to pHe 7.4. Voltage dependence for activation did not differ among all groups. AMD shifted the steady-state inactivation curve to more hyperpolarized potentials, with similar magnitudes for both pHes. The recovery from INa inactivation was delayed in the presence of AMD with similar profile in both pHes. Interestingly, the use-dependent properties of AMD was distinct at pHe 7.0 and 7.4. Finally, AMD was able to change the ex vivo ECG profile, however at pHe 7.0+AMD a larger increase in the RR and QRS duration and in the QT interval when compared to pHe 7.4 was found. CONCLUSIONS: The pharmacological properties of AMD upon NaV1.5 and isolated heart preparation depends on the pHe and its use in vivo during extracellular acidosis may cause a distinct biological response in the heart tissue.
Assuntos
Amiodarona , Animais , Ratos , Humanos , Amiodarona/farmacologia , Antiarrítmicos/farmacologia , Células HEK293 , Ratos Wistar , Canais de Sódio , Concentração de Íons de Hidrogênio , Canal de Sódio Disparado por Voltagem NAV1.5RESUMO
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.
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%: 0,213,35, 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.