右房峡部传导特性与心房扑动诱发的关系

The Relationship Between Unidirectional Block in Right Atrium Isthmus and Induced Atrial Flutter

在 10例室上性心动过速消融后及 2例窦性心动过缓心脏电生理检查中 ,依次进行低侧右房和冠状静脉窦口刺激 ,检出右房峡部双向阻滞 6例、双向传导 2例、单向阻滞 4例。在 3例峡部逆钟向阻滞者 ,低侧右房刺激诱发出短阵顺钟向心房扑动 (简称房扑 ) ;在 1例峡部顺钟向阻滞者 ,冠状静脉窦口刺激诱发出短阵逆钟向房扑。提示在无临床房扑史但有右房峡部单向阻滞者 ,可诱发短阵房扑 ,诱发房扑的类型与峡部阻滞方向及刺激位点有关。

Twelve cases were studied by pacing low lateral right atrium and coronary sinus ostium,of whom 10 cases were ablated for superventricular tachycardias and 2 cases had sinus bradycardia.It was found that 6 cases demonstrated bi directional block,2 cases bi directional conduction and 4 cases unidirectional block in right atrium isthmus.Temporary clockwise atrial flutter was induced by pacing at low lateral right atrium in 3 cases with the counterclockwise block in the isthmus.Temporary counterclockwise atrial flutter was induced by pacing at coronary sinus ostium in 1 case with clockwise block in the isthmus.The results suggest that temporary atrial flutter can be induced in persons who have unidirectional block in right atrium isthmus but clinical history of atrial flutter.The type of flutter induced is dependent on the blocking direction of the isthmus and the pacing site.