重复运动试验检测稳定性心绞痛患者心肌缺血预适应现象

为探讨冠心病稳定性心绞痛患者心肌缺心预适应现象的客观指标,选择稳定性心绞痛患者16例,按修定的Bruce方案,于首次活动平板运动试验后10 min行第二次活动平板运动试验,分析两次运动试验中心绞痛的发生率及出现时间、ST段压低最大值及持续时间、运动中和/或运动后心律失常发生率.结果发现,心绞痛发生率由首次运动试验的56.3%降至第二次运动试验的25%(P<0.01),心绞痛出现时间由首次运动试验的2.24±0.2 min延长至第二次运动试验的3.8±0.4 min (P<0.05);ST段压低最大值由首次运动试验的0.18±0.07 mV降至第二次运动试验的0.12±0.04 mV (P<0.01),ST段压低持续时间由首次运动试验的 6.42±0.8 min降至第二次运动试验的4.1±0.5 min (P<0.01);心律失常发生率由首次运动试验的43.8% 降至第二次运动试验的18.8%(P<0.01).结果提示,短暂心肌缺血可使心肌产生预适应现象,并对心脏产生保护作用.

Detection of Ischemic Preconditioning in Patients with Angina Pectoris Using Repetitive Exercise tests

Aim To explore the objective evidence of ischemic preconditioning (IP) in patients with stable angina (SA).Methods sixteen patients with SA underwent two times of treadmill exercise tests(TET) at the interval of 10 minutes according to Bruce protocal. The appeared rate and time of chest pain, maximal value and duration of ST segment depression, arrhythmias occurred during TET were analysed for different two tests. Results 9 patients (56.3%) complained of chest pain in the first test, however, only 4 of them (25%) did in the second one (P<0.01). The occurred time of chest pain was 2.24±0.2 min in the first test, 3.8±0.4 min in the second one (P<0.05). The maximal value of ST segment depression decreased from 0.18±0.07 mV in the first test to 0.12±0.04 mV in the second one (P<0.01), and duration of ST segment depression was down from 6.42±0.8 min in the first test to 4.1±0.5 min in the second one (P<0.01). The rate of arrhythmia decreased from 43.8% in the first test to 18.8% in the second one (P<0.01). Conclusions The present data demonstrated that transient ischemia of myocardium could result in ischemic preconditioning phenomenon, and protected heart from more serious damage at the definite interval of time.