左房房性心动过速三维电磁导管标测系统(Carto)标测与射频消融

目的探讨左房房性心动过速(房速)三维电磁导管标测系统(Carto)系统标测特点及射频消融价值.方法 9例左房房速患者,应用Carto系统标测左心房,实时重建左房三维电解剖图;根据电解剖图,判断房速类型局灶性或大折返性房速;于心房最早激动点处或折返环的关键峡部消融.结果 9例患者中共有10个房速.在冠状静脉窦(CS) 电极中、远端或近端均记录到相对提早A波;9个房速为局灶性房速,激动图显示最早激动点位于肺静脉口部(5个)、左房后壁(2个)、左心耳口部(1个)、左心耳体部(1个);1个为大折返性房速,折返经过右上肺静脉口部与卵圆窝之间关键峡部.8个局灶性房速在上述最早激动点处消融,均成功终止房速,1个左心耳体部房速消融失败;大折返性房速于关键峡部行线性消融,获成功;随访6～30个月,其中1例局灶性房速术后次日复发,再次消融成功;无并发症;成功病例手术时间为90～140 min,X线照射时间为8～16 min.结论本组结果提示,应用Carto系统标测左房房速,判断房速类型准确、快速;指导消融安全、有效,可减少X线照射时间,进一步提高消融成功率,特别是对于常规方法消融失败病例尤有帮助.

Electroanatomical mapping and radiofrequency ablation of atrial tachycardia in left atria

Objective To characterize the electroanatomical mapping and to assess the value of radiofrequency ablation of atrial tachycardia (AT) in left atria. Methods Nine patients with AT in left atria were studied. Three-dimensional electroanatomical maps were constructed in left atrium using electroanatomical mapping system (Carto). The type of AT (focal or macroreentrant) was identified by the electroanatomical maps, and the ablation targets were at the earliest activation sites or the isthmus of circuit. Results There were ten ATs in 9 cases. The relatively early A waves were recorded in middle, distal or proximal parts of coronary sinus catheter. Nine focal ATs were diagnosed. The activation maps demonstrated that the earliest activation sites were at the ostium of pulmonary veins ( n =5), posterior area of left atrium ( n =2), ostia of left atria appendage ( n =1) or left atria appendage ( n =1) respectively. One macroreeentrant AT was diagnosed, whose circuit propagated through the isthmus, formed by the right superior pulmonary vein and fossa ovalis. Eight focal ATs were all ablated successfully at the earliest activation sites, and one AT from left atria appendage was ablated unsuccessfully. Line of ablation was performed at the isthmus of the macroreentrant AT. During a period of 6-30 months follow-up, one patient with focal AT recurred and underwent another ablation with successful result. No complication occurred. The procedure time and the fluoroscopic time were 90-140 min, 8-16 min respectively in successful cases. Conclusion These results suggest that electroanatomical mapping of AT in left atria may facilitate rapid and accurate identification of the type of AT and guide ablation safely or effectively with less fluoroscopic time and higher success rate, especially in unsuccessful cases with conventional technique.