RESUMO
Experimental simulation of heart contusion accompanied by acute insufficiency of myocardial contractility was followed by examination of myocardial tissue samples using transmission electron microscopy. Analysis of microstructural changes in cardiomyocytes revealed characteristic defects in their contractile apparatus. The results were used to substantiate mechanisms underlying acute insufficiency of myocardial contractility resulting from heart contusion.
Assuntos
Contusões , Traumatismos Cardíacos , Contração Miocárdica , Miocárdio/patologia , Miócitos Cardíacos/patologia , Animais , Contusões/patologia , Contusões/fisiopatologia , Modelos Animais de Doenças , Traumatismos Cardíacos/patologia , Traumatismos Cardíacos/fisiopatologia , Humanos , Masculino , Ratos , Ratos WistarRESUMO
The experimental modeling of heart contusion which was accompanied by ventricular fibrillation development was performed in Wistar rats, with the electrocardiographic study and subsequent histological and histochemical examination of the myocardium samples. Following heart contusion, acute circulatory disturbances, muscle fiber fragmentation, cardiomyocyte overcontraction or relaxation were detected in the myocardium. Also, the increase of total and intracellular calcium ion content in the myocardium was demonstrated. It is suggested that the mechanism of ventricular fibrillation development after heart contusion is associated with the increase of calcium concentration in both the cardiomyocytes and intercellular spaces leading to uncoordinated cardiac contractions.
Assuntos
Traumatismos Cardíacos/patologia , Miocárdio/patologia , Ferimentos não Penetrantes/patologia , Animais , Cálcio/metabolismo , Circulação Coronária , Traumatismos Cardíacos/complicações , Traumatismos Cardíacos/fisiopatologia , Masculino , Contração Miocárdica , Miócitos Cardíacos/fisiologia , Ratos , Fibrilação Ventricular/etiologia , Fibrilação Ventricular/patologia , Fibrilação Ventricular/fisiopatologia , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/fisiopatologiaRESUMO
This morphohistochemical study was carried out using myocardial tissue samples obtained from subjects with heart contusion. The aim of the study was to elucidate the cause of ventricular fibrillation associated with alternative myocardial insufficiency. It is concluded that changes of Ca2+ ion content in the myocardial tissue may be one of the factors contributing to the development of ventricular fibrillation.
