典型心房扑动消融术后峡部时间间期的变化预测双向阻滞的价值

通过比较心房扑动 (简称房扑 )成功消融前后右心房峡部时间间期 ,分析峡部时间间期的延长程度对峡部完全性双向阻滞的预测价值。选择 1996～ 2 0 0 2年在我院行射频消融治疗的典型房扑患者 30例 ,男 2 3例、女 7例 ,年龄 4 7.85± 9.35岁 ,采用解剖和影像定位法 ,在冠状静脉窦口持续起搏下消融峡部。结果 :2 9例消融成功 ,达到双向传导阻滞的标准 ,成功率 96 .6 7%。消融后起搏信号至右房下侧壁的时间间期 (SAH1 2 )和起搏信号至冠状窦口CS3 4的时间间期明显延长 (14 0 .4 7± 2 0 .4 8msvs73.82± 13.0 1ms ;138.17± 15 .5 5msvs77.6 3± 8.36ms ,P <0 .0 0 0 1)。 2 9例中有 17例在完全性传导阻滞前可以记录到不完全性传导阻滞 ,峡部不完全性传导阻滞时SAH1 2 比术前增加 4 5 .4 9%± 8.7%。消融前后右心房峡部传导时间间期增加≥ 5 0 % ,预测峡部完全性双向传导阻滞的灵敏度 10 0 % ,特异度 83.3%。结论 :右心房峡部传导时间间期的定量分析是判断峡部完全性双向传导阻滞的有价值的方法。

Evaluation of Transisthmus Conduction Interval in Predicting Bidirectional Block After Ablation of Typical Atrial Flutter

The purpose of this study was to determine whether the extent of prolongation of the transisthmus interval after ablation predicts complete bidirectional block.Thirty consecutive patients underwent ablation procedures for isthmus-dependent atrial flutter. There were 23 men and 7 women( 47.85±9.35 years old). With the use of fluoroscopic view of anatomy,radiofrequency ablation was performed during coronary sinus pacing at a cycle length of 600ms. Results:Bi-directional block was achieved with ablation in 29(96.67%) of 30 patients. The transisthmus intervals before ablation and after complete transisthmus block were 73.82±13.01 ms and 140.47±20.48 ms,respectively,in the clockwise direction ( P <0.0001),and 77.63±8.36 ms and 138.17±15.55 ms,respectively,in the counterclockwise direction ( P <0.0001). A period of incomplete isthmus block was observed during 17(58%) of the 29 ablation procedures.The clockwise transisthmus intervals during incomplete block(107.65±21.33 ms) was 45.49%±8.7% longer than the baseline transisthmus intervals.An increase in the transisthmus interval by ≥50% in both directions after ablation predicted complete bi-directional block with 100% sensivitity and 83.3% specificity. Conclusion: The analysis of transisthmus interval is a valuable method for determining complete isthmus block.