单极电图对局灶性房性心动过速有效消融靶点的判定作用

Value of unipolar electrogram in identification of the successful target for radiofrequency catheter ablation of focal atrial tachycardia

目的 分析局灶性房性心动过速 (房速 )成功与非成功消融靶点的单极电图特点 ,探讨单极电图对房速有效消融靶点的判定作用。方法 对 15例局灶性房速患者进行射频消融治疗 ,术中同时记录消融电极导管的单极和双极标测电图。 结果 成功消融 14例房速。成功靶点 ( 14个 )和非成功靶点 ( 13个 )的双极电图 A波分别提前 ( 36± 15 ) m s和 ( 30± 11) ms( P<0 .0 5 )。成功靶点单极电图的心房波为完全负向“QS”样图形 ,本位曲折位于心房波的起始处 ;非成功靶点单极电图的心房波为“r S”样图形。结论 单极电图的“QS”样心房波对判定房速有效消融靶点具有极高的特异性和敏感性 。

Objectve To analyse the unipolar electrograms from successful and unsuccessful ablation sites of focal atrial tachycardia(AT),and evaluate the value of unipolar electrogram in identification of successful target. Methods Fifteen consecutive patients with focal AT were referred for radiofrequency catheter ablation(RFCA).Both unipolar (from the tip electrode of ablating catheter) and bipolar (from the distal pair of electrodes of ablating catheter)electrograms were recorded and used to identify the ablation target of focal AT. Results Successful ablation was obtained in 14 patients.Radiofrequency energy was delivered at a total of 27 atiral sites.The bipolar electrograms associated with successful ablation sites showed an earlier atrial deflection relative to P′ wave oneset [(36±15)]versus (30±11) ms, P <0.05)than the electrograms associatd with failed ablation sites.At the 14 successful abltaion sites,unipolar electrogram displayed a completely negative atrial wave (“QS” morphology) beginning with intrinsic deflection.However,at the 13 unsuccessful ablation sites,an “rS” morphology of atiral wave was shown on the unipolar electrogram. Conclusion The “QS” morphology of atrial wave on unipolar electrogram appears to represent a reliable marker in identification of successful ablation target of focal AT,with a high sensitivity and specificity.