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室壁运动异常与心律失常的关系尚不清楚。一种可能性是机械负荷直接影响心肌细胞的兴奋性与不应期。这种机制已被离体组织和动物研究所证实。致心律失常的可能机制:1.机械诱发的反应:受损心肌激活较慢,当周围正常心肌收缩时它仍处于电舒张状态。如心室收缩,受损节段被伸展而诱发电活动。电波面缓慢到达周围正常组织,此时后者不再处于不应期,从而再次激活。2.机械诱发的折返:除开梗塞心肌和心肌疤痕,相邻心肌纤维组不应期的不均匀改变可以诱发“功能性”单向阻滞。心房组织不应期相差11～16ms,心室肌不
The relationship between wall motion abnormalities and arrhythmia is unclear. One possibility is that mechanical loading directly affects the excitability and refractory period of cardiomyocytes. This mechanism has been confirmed by the Institute of Tissue and Animal Research. Probable mechanisms of arrhythmias: 1. Mechanically evoked responses: Slower myocardial activation is slow, and when normal peripheral myocardium contracts it is still in an electrically vasodilatory state. As ventricular contraction, damaged segments are stretched to induce electrical activity. Radio waves slowly reach the surrounding normal tissue, when the latter is no longer in refractory period, which reactivated. Mechanically induced reentry: In addition to infarction of myocardial and myocardial scarring, non-uniform changes in refractory period of adjacent myocardial fibrosis can induce “functional” unidirectional blockade. Atrial tissue refractory period difference 11 ~ 16ms, ventricular muscle does not