持续心房颤动时肺静脉口部有效不应期变化的时间进程及其逆转

为探讨持续心房颤动 (AF)肺静脉有效不应期 (ERP)变化的时间进程及其逆转 ,运用起搏方法建立AF模型 ,在起搏前和起搏后的第 1 ,2 ,3,4 ,5 ,6 ,7d对左上肺静脉口、左下肺静脉口、右上肺静脉口及右下肺静脉口的ERP进行测定。采用S1 S2 程序刺激 ,基础起搏周长 (S1 S1 )分别为 4 0 0 ,35 0 ,30 0 ,2 5 0 ,2 0 0ms,S2 为 2 0 0ms,以 5ms的步长递减。程序刺激结合猝发刺激对上述心房结构进行AF的诱发 ,记录AF的发生频率。上述相同方法对起搏停止后 1 ,2 ,3,4 ,5 ,6 ,2 4h 4个肺静脉口的ERP进行测定。结果 :各个基础起搏周长下 4个肺静脉口的ERP在AF后 1 ,2 ,3,4 ,5 ,6 ,7d逐渐缩短 ,且较AF前明显缩短 ,P <0 .0 5 ;AF终止后 4个肺静脉口的ERP逐渐延长 ,但AF终止后 0 ,1 ,2 ,3,4 ,5 ,6hERP与AF前相比仍有明显缩短 ,P <0 .0 5 ;AF终止后 2 4hERP基本恢复到AF前水平 ,随着AF持续时间的延长 4个肺静脉口AF的诱发率逐渐增高 ,与AF前相比 ,AF后 1 ,2 ,3,4 ,5 ,6 ,7dAF的诱发率明显增高 ,P <0 .0 5。结论 :随着AF持续 ,肺静脉的ERP逐渐缩短 ,AF的诱发率逐渐增高 ,AF终止后缩短的ERP逐渐延长致AF前水平。

The Time Course of in Goats With Experimental Persistent Atrial Fibrillation Pulmonary Vein Ostium Effective Refractory Period Changes and Its Reversal

To ivestigate the time course pulmonary vein effective refractory period(ERP) changes and its reversal during persistent atrial fibrillation(AF).Atrial fibrillation model were prepared by pacing left atrium in goats. The ERPs, of left suprerior pulmonary vein ostium(LSPV), left inferior pulmonary vein ostium(LIPV), right suprerior pulmonary vein ostium(RSPV), and right inferior pulmonary vein ostium(RIPV), were measured before pacing and after pacing for 1, 2, 3, 4, 5, 6, 7 days by S 1S 2 programmable stimulation,which basal pacing cycle length(S 1S 1) were respectively 400,350,300,250,200 ms,S 2 started from 200 ms, and decrement steps were 5 ms. AFs were induced by programmable stimulation combined with burst stimulation, and inducibility of AF was recorded. The ERPs, of LSPV,LIPV,RSPV and RIPV, were measured after AF stopping for 1, 2, 3, 4, 5, 6, 24 hs with identical program. Results:The ERPs, of LSPV, LIPV, RSPV and RIPV, gradually shortened, compared with before AF, P<0.05. After AFs stopping, the ERPs, of LSPV, LIPV, RSPV and RIPV ,gradually increased, but after AFs stopping for 1,2,3,4,5,6 hs, the ERPs were still significantly short compared with before AF, P<0.05, and after AFs stopping for 24 hs, the ERPs returned to the level of before AF, P>0.05. The inducibility of AFs, of LSPV, LIPV, RSPV and RIPV, increasedwith AF elongation, compared with before AF, P<0.05. Conclusion:With AF persistence, pulmonary veins ERPs gradually shorten, the inducibility of AFs gradually increase, and after AF stopping, ERPs gradually return to the level of before AF.