RESUMO
Previous studies have suggested that the jaggedness of the healed or healing infarct edge influences cardiac electrical stability. However, these findings have been based on histological observations rather than quantitative measurements. The aim of this study was to assess infarct jaggedness by calculating its fractal dimension and to examine how this influences cardiac electrical stability during late infarct healing in the rabbit. Using programmed electrical stimulation, it was found that the fractal dimension did not differ significantly in 19 rabbits that had inducible ventricular tachycardia and 16 that did not. We conclude from these studies in the mature rabbit that infarct edge jaggedness does not influence the ease with which ventricular tachycardia is induced during late myocardial infarct healing.
Assuntos
Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Função Ventricular/fisiologia , Cicatrização , Animais , Modelos Animais de Doenças , Feminino , Fractais , Processamento de Imagem Assistida por Computador , Masculino , Coelhos , Taquicardia Ventricular/fisiopatologiaRESUMO
Cells that are apoptotic and comprise less than 2% of the total cellular population are difficult to detect by conventional methods (i.e., DNA ladder). We discuss a new methodological technique, PCR-amplified DNA ladder, to detect very low levels of DNA fragmentation (indicative of apoptosis) in a myocardial infarct heart failure model. Results and methodology are contrasted with the traditional DNA ladder technique.
