六分钟步行运动对充血性心力衰竭患者QT离散度的影响

目的 :探讨QT离散度 (QTd)在充血性心力衰竭 (CHF)患者中的临床意义以及接近CHF患者日常生活活动的 6min步行运动实验对其QTd的影响。方法 :2 8例CHF患者及 2 2例健康对照者进行 6min步行实验 ,运动前后做十二导联同步心电图 ,测量运动前后QTd和QTcd。结果 :无论运动前还是运动后 ,CHF组QTd ,QTcd值均大于对照组 (P <0 .0 1)。CHF组患者运动后QTd(P <0 .0 1)和QTcd(P <0 .0 1)均较运动前明显缩短 ,而对照组无明显变化。结论 :充血性心力衰竭患者QT离散度较健康对照者显著增加 ;适量运动可能能够改善CHF患者的心室复极电不稳定性

EFFECTS OF 6-MINUTE WALK TEST ON THE QTD IN PATIENTS WITH CONGESTIVE HEART FAILURE

Objective:To investigate the clinical value of QT dispersion(QTd) and the effects of the exercise mimicing the patient's day-to-day activities--6-minute walk test(6-MWT) on QTd in patients with congestive heart failure (CHF).Methods:Twerty_two normal subjects and 28 patients with CHF underwent 6-MWT.Before and after 6-MWT, standardized 12-lead surface ECGs were obtained to measure QTd and heart rate-corrected QTd(QTcd).Results:Both before and after 6-MWT,the QTd and QTcd in patients with CHF were longer than those in the controls ( P <0.001).QTd and QTcd after 6-MWT were significantly shorter than those before 6-MWT in patients with CHF( P =0.07,and 0.018),but there were not significant difference in the controls.Conclusions:QTd and QTcd are longer in patients with CHF than in normal subjects;moderate exercise may improve the inhomogeneity of ventricular repolarization dispersion.