Assuntos
Cardiomiopatia Hipertrófica/tratamento farmacológico , Ativação do Canal Iônico/efeitos dos fármacos , Mitocôndrias Cardíacas/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Atorvastatina , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/metabolismo , Cardiomiopatia Hipertrófica/patologia , Cardiotônicos/farmacologia , Células Cultivadas , Ciclosporina/farmacologia , Ácidos Heptanoicos/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Confocal , Mitocôndrias Cardíacas/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Poro de Transição de Permeabilidade Mitocondrial , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Pirróis/farmacologia , Fatores de TempoRESUMO
AIMS: To study the predictive value of wavelet decomposition, as demonstrated by the signal-averaged ECG, in order to identify patients with hypertrophic cardiomyopathy at increased risk for malignant ventricular arrhythmias or sudden death. METHODS AND RESULTS: Two hundred and forty-six patients with hypertrophic cardiomyopathy were studied. During a mean follow-up of 68 +/- 17 months 32 patients died, of whom 17 died suddenly. Patients with sudden death, together with eight patients with a history of ventricular fibrillation (sudden death/ventricular fibrillation group) were analysed and compared to the other 221 patients as well as to a subgroup of 82 patients without a history of syncope, ventricular arrhythmias on a long-term ECG recording or a family history of sudden death. There were no differences in mean values of the four wavelet decomposition parameters among patients in the sudden death/ ventricular fibrillation group, those without sudden death/ ventricular fibrillation or patients in the low risk group. There were, however, significant differences between patients dying non-suddenly and patients being alive at the end of follow-up. Eighty-seven patients (35%) demonstrated evidence of non-sustained ventricular tachycardia on a long-term ECG. Analysis of wavelet decomposition resulted in abnormal findings in these patients more often than in those without ventricular arrhythmias. CONCLUSION: The usefulness of wavelet decomposition analysis in predicting sudden death or ventricular fibrillation is limited in patients with hypertrophic cardiomyopathy. It may, however, play a role in identifying patients at risk of dying non-suddenly and of patients with non-sustained ventricular tachycardia.
Assuntos
Cardiomiopatia Hipertrófica/classificação , Morte Súbita Cardíaca/prevenção & controle , Eletrocardiografia , Medição de Risco/métodos , Processamento de Sinais Assistido por Computador , Fibrilação Ventricular/classificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cardiomiopatia Hipertrófica/mortalidade , Criança , Eletrocardiografia Ambulatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Valores de Referência , Sensibilidade e Especificidade , Fibrilação Ventricular/mortalidadeRESUMO
Hypertrophic cardiomyopathy carries an increased risk of sudden death. The aim of the present study was to assess the predictive value of the signal-averaged ECG, analysed in the time domain and using a new method, spectral turbulence analysis, for the identification of high-risk patients. Two-hundred and forty-six patients with hypertrophic cardiomyopathy were studied. During a mean follow-up of 68 +/- 17 months, 17 patients died suddenly. Patients with sudden death (SD) and/or a history of ventricular fibrillation (VF; n = 25) were compared to patients without SD/VF (n = 221) and to patients without any recognised risk factors for SD (n = 82). There were no differences in mean values of the time domain or spectral turbulence parameters analysed between patients in the SD/VF group and the patients without SD/VF or in the low-risk group. It is concluded that the clinical usefulness of the signal-averaged ECG, analysed in the time domain or as spectral turbulence analysis, is limited in identifying high-risk patients with hypertrophic cardiomyopathy.