高频起搏犬房颤模型心房重塑及窦房结和房室结功能的变化  

Effect of high-rate left atrial pacing on atrial remodeling and functions of sinoatrial node and atrioventricular node in dogs

作　　者：刘丽娟[1] 姚凤娟[2] 彭龙云[1] 李嘉翔[1] 卢贵华[1] 劳妙婵[1] 陈宣兰[1] 吴素华[1] 高修仁[1] 

机构地区：[1]中山大学附属第一医院心内科,广东广州510080 [2]中山大学附属第一医院超声科,广东广州510080

出　　处：《中国病理生理杂志》2013年第2期248-254,共7页Chinese Journal of Pathophysiology

基　　金：广东省社会发展计划重点项目(No.2010B031500027)

摘　　要：目的:持续高频起搏犬左心房,观察房颤(AF)发生率、心房重塑以及窦房结、房室结传导功能。方法:健康比格犬15只随机分为起搏组(P组,n=9)和对照组(N组,n=6)。2组均在左心房心外膜缝合固定一起搏电极,P组以400 min-1的频率起搏,N组不起搏。采用程序起搏技术测定电生理参数。结果:(1)4周后P组阵发性AF和持续性AF的诱发率与N组比较差异均有统计学意义(分别P<0.05,P<0.01),P组第2周2只犬自发AF,第4周AF诱发率达100%,且持续性AF的发生率高。(2)P组4周后心房有效不应期(AERP)在不同基本起搏周期(250 ms、300 ms和350 ms)时均较N组缩短(P<0.05);房室结文氏点(AVN-Wen)较N组有意义延长[(294.44±26.03)min-1 vs(328.33±24.01)min-1,P<0.05];房室结有效不应期(AVERP)在不同起搏周期均明显延长(P<0.01)。(3)与N组比较,P组4周后窦房结恢复时间(SNRT)和校正恢复时间(cSNRT)均延长(P<0.01);P波时限2组比较差异没有统计学意义(P>0.05)。(4)P组2周后心脏超声与N组比较显示左心房前后、上下、左右径都有明显增大(P<0.01),右心房上下增大(P<0.05)。结论:持续4周心房高频起搏后房颤发生率高,心房肌、窦房结和房室结电生理发生特征性的相应改变,左、右心房不同程度扩大,提示电重塑、结构重塑与房颤的发生关系密切。AIM： To determine whether sinoatrial node （SAN） and atrioventricular node （AVN） undergo functional remodeling during atrial fibrillation （AF）. METHODS： The Beagle dogs were randomized into pacing group （ n = 9） and control group （ n = 6）. In open-chest dogs, the electrode catheters were sutured at left atria for pacing and data recording. SAN and AVN conductive properties were studied. The dogs in pacing group underwent 4 weeks of high-rate left atrial pacing （400 min- 1 ）. The dogs in control group were not subject to pacing. RESULTS： The animal model of chronic AF was successfully established by pacing the left atrium at 400 rain - ~ in the dogs. Two of those animals were recorded with spontaneous AF at the end of 2 weeks, and the induction rate of AF reached 100% following 4 weeks of pacing. The inci- dences of paroxysmal AF and permanent AF were significantly increased by pacing compared to control group. After 4 weeks of pacing, atrial effective refractory periods （AERP） at various at pacing cycle lengths （PCL; 250 ms, 300 ms and 350 ms） were all statistically shorter than those in control group. Compared with control group, a longer AVN Wenckebach point [ （294. 44 ＋ 26. 06） rain - 1 vs （328.33 ~ 24. 01 ） min - ~, P 〈 0. 05 ] and longer atrioventricular node effective refractory period （AVERP） （P 〈0. 01 ） in pacing group were observed. The sinus node recovery time （SNRT） and corrected SNRT both showed significant increases. No significant change of P-wave and PA interval between the two groups was found. The left atrial dimensions （anteroposterior, superoinferior and left-right diameters） and the right atrial superoinferior diameter were measured to be significantly increased after 2 weeks of pacing. CONCLUSION ： The animal model of left atrium pa- cing can induce AF occurrence with a higher incidence. The characteristic electrophysiological indexes about atria, AVN and SAN were observed during AF in the canine model, indicating that elect

关 键 词：心房纤颤 窦房结 房室结 重塑 

分 类 号：R363[医药卫生—病理学]