持续性心房颤动山羊模型的心房单极电极标测

在持续性心房颤动 (简称房颤 )山羊模型上 ,研究心房不同部位房颤周长 (AFCL)及单极心外膜电图的差异 ,并利用激动标测图分析房颤时的蝉联现象。将 83个电极分别缝合于 7只山羊的左心房游离壁、左心耳、Bachmann束 (BB)、右心耳游离壁的心外膜。利用自动房颤刺激器维持房颤 ,待房颤持续 4周后 ,取 16s的心外膜电图作分析。利用单极电图标记局部激动时间 ,并根据单极电图的形态特点将其标记为正常电位 (单电位和短的双电位 )及异常电位 (长的双电位、三电位及碎裂电位 )。根据左心房局部激动时间重建等电位激动标测图 ,如超过 7次连续心房搏动经过相同路径 ,则定义为蝉联片段。在左心房、左心耳、BB、右心耳及右心房的AFCL分别为 94 .9± 4 .6 ,95 .7±4 .4 ,10 5 .7± 6 .5 (与其他部位比较 ,P <0 .0 5 ) ,99.2± 8.0及 98.5± 6 .3ms ;异常电位的百分比分别为 2 0 .9%± 6 .3% ,2 7.8%± 11.8% ,5 7.4 %± 7.8% (与其他部位比较 ,P <0 .0 1) ,18.6 %± 9.7%和 19.4 %± 3.9%。在所记录的 16s房颤过程中 ,左心房共有 70 5次心搏 ,其中 6 8次 (9.6 % )属于蝉联片段。结论 :在山羊持续房颤模型 ,BB的AFCL最长 ,异常电位的发生率最高 ,提示BB在房颤的维持上起重要作用。蝉联现象的存在表明房颤时心房激动并

Mapping of Persistent Atrial Fibrillation in Chronically Instrumented Goat Model With Unipolar Atrial Electrodes

The aim of the study is to compare the difference of atrial fibrillation cycle length (AFCL) and unipolar electrograms characteristics from different regions of atria during persistent atrial fibrillation (AF) in goat model,and to evaluate linking phenomenon during AF with activation maps.Seven goats were instrumented with 83 electrodes that distributed over left atrium free wall (LA),left atrial appendage (LAA),Bachmann′s bundle (BB),right atrial appendage (RAA) and right atrium free wall (RA).AF was maintained by an automatic atrial fibrillator.After AF had persisted for 4 weeks,a period of 16 seconds AF was taken for data analysis.Local activation times of the epicardial unipolar electrograms were marked and labeled as either normal (single,short double) or abnormal (long double,triple and fragmented) potentials.Activation maps were reconstructed from the local activation time in left atrium.If more than 7 consecutive beats followed the same activation course during AF,they were termed as episode of linking.The AFCL were 94.9±4.6,95.7±4.4,105.7±6.5 ( P <0.05),99.2± 8.0 and 98.5±6.3 ms,in LA,LAA,BB,RAA and RA respectively.The percentages of abnormal potentials were 20.9%±6.3%,27.8%±11.8%,57.4%±7.8% ( P <0.01),18.6%±9.7% and 19.4%±3.9% respectively.During 16 seconds of AF there were 705 beats in LA,68 (9.6%) beats of them belong to episode of linking.Conclusions:During persisted AF in the goat model,BB had the longest AFCL and more percentage of abnormal potentials than other regions,which suggest that BB may play an important role in the maintenance of AF.