运动负荷超声心动图评价起搏器频率适应者的心功能

目的　应用运动负荷超声心动图评价频率适应性起搏器对心功能的影响。方法　对 4 4例植入频率适应性起搏器的患者行运动负荷超声检查 ,分别于非频率适应和频率适应两种起搏状态时进行仰卧位踏车实验。记录踏车运动持续时间、最大负荷量并测定踏车前及踏车高峰时的心率 (HR)和心输出量 (CO)。结果　运动高峰时频率适应性起搏的 HR和 CO明显高于非频率适应性起搏 (P<0 .0 1)。而静息状态下非频率适应性和频率适应性起搏时的 HR和 CO无显著差异 ,这两种起搏方式时的运动持续时间和最大负荷量亦无显著差异。结论　运动负荷超声较静态超声评价心功能有明显优势。运动时频率适应性起搏能明显提高 HR和 CO。

Exercise Stress Echocardiogaphy Assessment of Cardiac Function in Patients with Rate-adaptive Pacemaker

Objective To investigate the effects of exercise stress echocardiography (E-Echo)on cardiac function in patients with rate-adaptive pacemakers.Methods E-Echo was performed in 44 patients with pacemakers.All patients underwent supine bicycle exercise tests in fixed-rate and adaptive pacing mode.The exercise persisting time,workload,heart rate and cardiac output were calculated.Results The maximum heart rate and cardiac output during exercise tests were significantly enhanced in rate-adaptive pacing(P<0.01),but there were no differences in rest time.The exercise persisting time and workload were not significantly increased in rate adaptive pacing than those in fixed-rate pacing.Conclusions E-Echo is better than rest echocardiography for assessment of cardiac function in patients with pacemakers.The heart rate and cardiac output were obviously increased in patients with rate-adaptive pacemakers.