人类自发的阵发性心房颤动导致的心房有效不应期及其频率适应性的变化

探讨人类自发的阵发性心房颤动 (AF)导致的心房有效不应期 (ERP)及其频率适应性的变化。对 12例在我院进行心腔内电生理检查和 或射频消融术且术中出现阵发性AF的患者 ,于AF发生前及AF终止后分别以基础周长 5 0 0 ,40 0和 30 0ms的刺激测量心房ERP。结果 :AF持续时间为 8.9± 2 .0min ,以周长为 5 0 0 ,40 0和 30 0ms行S1 S1 刺激 ,在AF发生前 ,ERP分别为2 2 3± 39,2 13± 33和 2 0 1± 2 1ms ,AF终止后 ,ERP分别为 189± 32 ,186± 35和 180± 2 3ms ,其缩短率分别为 15 .5 %± 4.0 % ,12 .9%± 3.1%和 10 .8%± 3.0 % ,与AF发生前相比 ,P均 <0 .0 1。心房ERP在低频率时的缩短程度大于在高频率时 ,各起搏周长下ERP缩短的程度比较具有显著统计学差异 (P <0 .0 5 )。AF终止后 10minERP恢复至AF前水平。结论 :人类几分钟的阵发性AF可使ERP缩短 ,并且可造成ERP频率适应不良

Changes in Atrial Effective Refractory Period and Its Rate Adaptation Caused by Spontaneous Paroxysmal Atrial Fibrillation in Humans

This study measures the changes of atrial effective refractory period (ERP) and its rate adaptation after spontaneous paroxysmal atrial fibrillation (AF) in humans.In 12 patients referred to Xijing Hospital for electrophysiological testing and/or radiofrequency catheter ablation,the ERP was measured before and after spontaneous paroxysmal AF at drive cycle lengths of 500,400 and 300 ms respectivecy. Results:The preAF ERPs at 500, 400 and 300 ms were 223±39,213±33 and 201±21 ms respectively.The duration of AF was 8.9±2.0 minutes.Immediately upon AF conversion to sinus rhythm, atrial ERPs at drive cycle lengths of 500,400 and 300 ms were 189±32,186±35 and 180±23 ms respectively (allP<0.01 versus preAF).Percentage of atrial ERP reduction at drive cycle lengths of 500,400 and 300 ms were 15.5%±4.0%,12.9%±3.1% and 10.8%±3.0% respectively.The reduction of atrial ERP at slow rate was more than that at rapid rate.There was a significant statistic difference between reduced percentages at every two basic drive cycle lengths (P<0.05).The postAF ERP returned to the preAF ERP value after about 10 minutes.Conclusion:In human, paroxysmal AF of several minutes is sufficient to shorten the ERP and can cause ERP maladaptation to rate.Chinese Journal of Cardiac Pacing and Electrophysiology,2000,14(2):96～97]Atrial fibrillation,paroxysmal Effective refractory period Rate Human