射频消融术中房室结快慢径前传不应期变化及其意义

探讨 2 7例房室结折返性心动过速 (AVNRT)病人射频消融术 (RFCA)中房室结前传有效不应期 (ERP)变化的意义 ,应用心房程序刺激法测定放电前后房室结快慢径前传ERP并据此指导治疗。结果 :2 7例AVNRT病人房室结ERP对射频电流呈 4种反应 :①快径前传ERP缩短 10例。其中 6例表现为引起跳跃的S2 间期缩短 ,无心房回波 ,异丙肾上腺素可诱发AVNRT ,继续寻找并消融慢径 ,跳跃现象消失。 4例前传ERP由 36 0± 15ms缩至 170± 8ms,跳跃消失 ,异丙肾上腺素不能诱发AVNRT ,不再消融。②快径前传ERP延长 6例 ,由 36 0± 10ms增至 430± 12ms。延长S2 与S1耦联间期行心房程序刺激 ,跳跃再现 ,继续寻找并消融慢径至跳跃消失。③慢径前传ERP缩短 5例。术中AVNRT频率由 170± 14次 /分增至 2 30± 11次 /分。继续消融慢径 ,跳跃消失。④慢径前传ERP延长 6例 ,表现为AVNRT的频率减慢 ,继续消融慢径获成功。上述病人经 3.3± 0 .8( 2 .0～ 4.5 )年的随访 ,未见房室阻滞 (AVB)发生 ,亦无AVNRT复发。结论 :对于少数AVNRT病人 ,借助术中房室结前传ERP的变化指导消融 ,可望提高治疗效率、减少复发机率、避免AVB的发生。

Changes and Significance of Antegrade Effective Refractory Period of the Fast and Slow Pathway During Radiofrequency Current Ablation in Patients With Atrioventricular Nodal Reentrant Tachycardia.

To investigate changes and significance of antegrade effective refractory period(ERP) of the fast and slow pathway during radiofrequency current ablation(RFCA) in 27 patients with atrioventricular nodal reentrant tachycardia(AVNRT),the antegrade ERP of the fast and slow pathway were measured before and after radiofrequency current delivery and RFCA was guided based on the changes of ERP.Results:There were 4 kinds of responses to radiofrequency current of atrioventricular node in the 27 patients with AVNRT.①The antegrade ERP of fast pathway was shortened in 10 patients.6 of the 10 patients manifested as shortening of S 1S 2 interval that triggered atrial wave-H wave(AH) leaping,no atrial echo but AVNRT induced by isoprenaline and the slow pathway was further mapped and ablated.In other 4 patients,the antegrade ERP of fast pathway significantly shorted from 360±15 ms to 170±8 ms and AH leaping disappeared,which meaned successful ablation.②The antegrade ERP of fast pathway increased from 360±10 ms to 430±12 ms in 6 patients.While these patients received atrial programmed stimulation with prolongated S 1S 2 interval,AH leaping reappeared,thus receiving ablation of slow pathway again.③The antegrade ERP of slow pathway was shortened and the rate of AVNRT from 170±14 bpm to 230 ±11 bpm in 5 patients.As the slow pathway was further ablated,AH leaping disappeared.④The antegrade ERP of slow pathway was prolongated and the rate of AVNRT slowed in 6 patients,in which the second ablating of slow pathway was necessary.There were no both atrioventricular block(AVB) and AVNRT recurrence in the 27 patients during 3.3±0.8(2.0～4.5)years follow up.Conclusion:AVNRT recurrence could be decreased and AVB could be avoided by guiding ablation based on the changes of antegrade ERP of atrioventricular node during RFCA for some patients with AVNRT.