心房颤动电生理重构的实验研究

目的 :研究心房颤动 (atrialfibrillation ,AF)时心房肌的电生理重构。方法 :快速持续起搏犬右心房 8～ 10周 ,制备持续性AF模型。比较对照犬 ( 8只 )与起搏犬 ( 10只 )的有效不应期 (effectiverefractoryperiod ,ERP)和心房颤动波周长 (atrialfibrillationcyclelength ,AFCL)的变化来分析心房肌的电生理重构。结果 :起搏组P波时间和PA间期比起搏前明显延长 (P波时间 90 5± 10 5对 5 3 6± 8 3ms ;PA间期 5 9 6± 8 8对 3 8 6± 11 4ms ,P <0 0 5 )。经程序刺激ERP较对照组明显缩短 (S1S13 0 0ms 115± 2 3对 15 0± 2 1;S1S14 0 0ms 10 5± 2 7对 15 4± 2 4ms ,P <0 0 5 )。同一心房不同部位的ERP和AFCL也存在差异。结论 :心房率的长期变化可引起ERP和AFCL的变化 ,即心房肌发生电生理重构 ,而且不同部位心房肌电生理重构是不同的。

Experimental study of atrial electrical remodeling in atrial fibrillation

Objeetive: The aim of this study was to investigate the atrial myoeardium charateristies of electrieal remodeling inatrial fibrillation (AF). Methods: After 8 to 10 weeks of sustained rapid right atrial pacing,sustained AF model came into being. The atriai effective refractory period (ERP) and atrial fibrillation cycle length (AFCL) were measured at multiple sites incontrol group and pacing group. According to atrial ERP and AFCL changes, the mechanism leading to myocardium electricalremodeling was investigated. Results: P-wave duration and PA interval significantly increased in pacing group (P-wave duration 90.5 + 10.5 vs 53.6±8.3 ms; PA interval 59.6 + 8.8 vs 38.6 + 11.4 ms, p < 0.05). ERP significantly shortened afterprogrammed stimulation (S1S1 300 ms 115±23 vs 150+ 21 ms;S1S1 400 ms 105 + 27 vs 154 + 24 ms, P < 0.05).ERP andAFCL at different location of the same atrial were difference. Conclusion: Changes in ERP and AFCL resulted from prolongedchanges in atrial rate. Atrial produced electrical remodeling which was, difference in different location of atrial.