无症状心肌缺血阈的临床意义

Mycardial ischemic threshold of silent mycardial ischemia

目的 评价无症状心肌缺血阈。方法 62例冠心病患者 ,通过 2 4小时心电监测 ,检测冠心病患者的心肌缺血阈值 (MIT)、MIT的变异度 (IV) ,以及每阵缺血发作持续时间 (TMI)和ST段最大位移 (STm) ,以及昼夜缺血阵数 (IN)。结果 共检出 5 0 6阵心肌缺血 ,93 .5 %在ST段压低时心率加快 ,夜间心肌缺血阈值较低 ,但缺血时间及ST段压低程度明显重于昼间。结论 高心肌缺血阈、低心肌变异率与心肌耗氧增加有关 ,低心肌缺血阈。

Objective To evaluate the myocardial ischemic threshold of silentment myocardium.Methods 62 Patients with coronary artery disease were investigated by 24 hour ambulatory electro-cardiography.To observe the myocardial ischemic threshold,variability of cardial ischemic threshold,duration of every ischemic episodes.Results The results indicates that 93.5% fast heart rate with ST depression among the total 506 ischemic episodes and noctural ischemias had lower threshold and longer mean ischemic time as well as deeper ST depression.Conclusion High myocardial ischemic threshold with low variability of myocardial threshold correlated with increased oxygen comsumption of myocardium;low mycardial ischemic threshold and high variability of mycardial ischemic threshold correlate with spasm of coronary artery.