摘要
QT dispersion(QTd,equals maximal minus minimal QT interval on a standard ECG) has been shown to reflect inhomogeneity of myocardial repolarization and cardial electrical instability, hence,been proposed to be associated with ventricular arrhythmias.But the intrinsical mechanism of QTd is incompletely understood. Contributing to QTd are differences of action potential duration(APD) in the three-dimensional structure of ventricular myocardium, which is identified to own three cell subtypes:endocardial, midmyocardial(M cells) and epicardial cells.And findings suggest that regional differences in the duration of the M cell action potential may lead transmural and spatial dispersion of repolarization. Autonomic nerves by combining receptors on the myocardial cells,especially M cells affect significantly the APD.Concordance between heterogeneity of ventricular myocardium and heterogeneity of autonomic innervation in heart provide support for the role of autonomic nerve in the generation of the QT dispersion.
QT dispersion(QTd,equals maximal minus minimal QT interval on a standard ECG) has been shown to reflect inhomogeneity of myocardial repolarization and cardial electrical instability, hence,been proposed to be associated with ventricular arrhythmias.But the intrinsical mechanism of QTd is incompletely understood. Contributing to QTd are differences of action potential duration(APD) in the three-dimensional structure of ventricular myocardium, which is identified to own three cell subtypes:endocardial, midmyocardial(M cells) and epicardial cells.And findings suggest that regional differences in the duration of the M cell action potential may lead transmural and spatial dispersion of repolarization. Autonomic nerves by combining receptors on the myocardial cells,especially M cells affect significantly the APD.Concordance between heterogeneity of ventricular myocardium and heterogeneity of autonomic innervation in heart provide support for the role of autonomic nerve in the generation of the QT dispersion.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2000年第11期1236-1239,共4页
Chinese Journal of Pathophysiology
关键词
自主神经系统心肌
动作电位
QT离散度
Autonomic nervous system
Myocardium
Arrhythmia
Action potentials