中年女性不同运动耐量试验QT间期恢复性质的比较

目的观察中年女性QT间期恢复性质是否受运动耐量影响。方法 80名中年女性根据接受平板运动心电图检查,根据运动耐量中位数分为高运动耐量组(HEC组)和低运动耐量组(LEC组)。记录完整运动过程的心电图并测量连续的QT和TQ间期。利用指数方程对连续的QT和TQ间期进行拟和并绘制TQ间期恢复曲线(QTRC),并计算最大斜率(Smax)。结果 69例完成实验(LEC组34例,HEC组35例),运动过程中LEC组女性QT间期(41±10 ms/Met vs.29±3 ms/Met,P=0.001)和TQ间期(46±12 ms/Met vs41±7 ms/Met,P=0.046)的变化率都明显高于HEC组,QT间期和TQ间期变化幅度比值也较HEC组有所升高(0.41±0.09 vs 0.36±0.07,P=0.003);LEC组QTRC坡度明显高于HEC组(1.43±0.44 vs 1.13±0.34,P=0.002)。结论中年女性QT间期恢复性质与运动耐量有关。

Comparison on QT restitution properties in middle-aged women with different exercise capacities

Objective To investigate whether QT restitution property of middle-aged women is affected by the exercise capacity.Methods Treadmill exercise tests were performed in 80 middle aged women.69 cases were divided into the low exercise capacity group（LEC group） and the high exercise capacity group（HEC group） by the median exercise capacities.Sequential QT intervals and their preceding TQ intervals were measured and the QT restitution curve（QTRC） was constructed.2 exponential equations were used to match the data and calculate the slope of QTRC,respectively.Results With the exercise level elevating,the women in the LEC group had a higher change rate of QT intervals（41±10 ms/Met vs.29±3 ms/Met,P=0.001） and TQ intervals（46±12 ms/Met vs.41±7 ms/Met,P=0.046）,and the ratio of QT interval alterations to QT interval alterations increased（0.41±0.09 vs.0.36±0.07,P=0.003）.Compared with HEC group.The Smax of the QTRC in the LEC group were bigger than that in the HEC group（1.43±0.44 vs.1.13±0.34,P=0.002）.There was an inverse relationship between Smax and exercise capacity（r=-0.43,P=0.001）.Conclusion QT restitution properties in middle-aged women is related to their exercise capacity.