房室结慢径消融对心房电生理性质的影响

目的 慢径消融降低了心房颤动(房颤)的易感性,但具体机制不明.本文旨在探讨消融后心房电生理性质的改变及其具体机制.方法 32例房室结折返性心动过速患者,测量射频消融前后窦性心率及高位右心房、低位右心房、冠状静脉窦近端和远端各部位的有效不应期和易感窗口,以及房室结快径前传不应期的变化.结果 (1)慢径消融前后下列部位的有效不应期的变化分别为:冠状静脉窦近端(21 8.1±21.8)ms,(235.3±23.6)ms,P＜0.0001;冠状静脉窦远端(230.9±21.0)ms,(244.7±25.1)ms,P＜0.01;低位右心房(198.8±26.7)ms,(219.7±28.7)ms,P＜0.005;高位右心房(214.4±35.1)ms,(213.4±37.3)ms,P=0.6.(2)在消融术后,房颤的诱发比例下降,冠状静脉窦近端的易感窗口显著降低(P=0.03),冠状静脉窦远端和低位右心房的易感窗口有所降低,高位右心房的易感窗口不变,但差异无统计学意义.(3)消融后窦性心率有一定程度的上升(72.1±5.6)次/min对(74±6.8)次/min,但差异无统计学意义(P=0.17).(4)慢径消融使快径前传不应期缩短,消融前后分别为(391±55)ms,(369±78)ms,P＜0.01.结论 慢径消融使心房多部位的电生理性质发生了改变,导致冠状静脉窦近端和远端,以及低位右心房的有效不应期延长,房颤诱发几率降低.该现象的原因可能与消融造成的迷走神经功能改变有关.     

房室结慢径消融对心房电生理性质的影响

Objective The ablation of the atrioventricular node slow pathway may reduce the inducibility of atrial fibrillation (AF) ,but the mechanisms remain unknown. We tried to investigate the impact of ablation on atria refractory period, and to elucidate the underlying mechanism. Methods Thirty-two patients with atrioventricular node reentrant tachycardia (AVNRT) were enrolled in the study. Atria effective refractory period (ERP) and vulnerable window (VW) at high right atrium (HRA),inferior right atrium (IRA),distal (CSd) and proximal CS (CSp) ,as well as sinus rate (SR) and effective refractory period of fast pathway (FERP) were measured before and after ablation. Results ( 1 ) After ablation, the ERP at HRA did not change:(214. 4 ± 35. 1 ) ms, (213.4 ± 37. 3) ms, P = 0. 6, on the other hand, the ERPs at following sites were significantly prolonged:CSp(218. 1 ±21.8)ms, (235.3 ± 23.6) ms,P ＜0. 0001 ;CSd(230. 9 ±21.0) ms, (244. 7 ±25. 1)ms,P＜0. 01;IRA(198.8 ±26.7)ms,(219.7 ±28. 7) ms,P ＜ 0.005,respectively. (2) The VW of HRA remained unchanged after ablation, while the VWs of CSp, CSd and IRA trended to decline despite no statistic significant. (3)SR showed a little increasing but without statistic significant after ablation (P = 0. 17 ).(4) ERP of fast pathway was significantly decreased after ablation: ( 391 ± 55 ) ms, ( 369 ± 78 ) ms, P ＜ 0. 01.Conclusions The decrease of ERPs at CS and IRA, as well as F-ERP after ablation may decline the inducibility of atrial fibrillation and indicates regional vagal denervation to the atrium.     

房室结慢径消融后对快径前传不应期影响

<正> 房室结双径路(DAVNP)是形成房室结折返性心动过速的必须电生理基础,射频消融房室结慢径路是治疗房室结折返性心动过速(AVNRT)安全、有效的方法.射频消融慢径路后有学者发现快径路前传不应期发生改变,本文对慢径路消融后快径路前传不应期改变,探讨慢径路消融后对快径路前传不应期的影响.1 资料和方法1.1 病例选择经电生理检查证实为DAVNP伴AVNRT患者44例,其中男性21例,女性23例;年龄15～77岁,平均年龄46.77±14.89岁;病史0.6～30年,均有反复发作室上性心动过速史.无器质性心脏病证据.合并房室结快径经消融者未选入.     

射频消融房室结慢径对诱发Ⅰ型房扑的影响

目的 观察射频消融房室结慢径对诱发Ⅰ型房扑（ＡＦＬ）的影响，分析这２种心和人常之间的关系和探讨房室结慢径的本质。方法 ２１例房室结折返性心动过速（ＡＶＮＲＴ）患，分别于射频消融前后行心房程序电刺激恨ＡＦＬ。结果 慢径消融前ＡＦＬ恨率为９０．４８％，慢径消融后 诱发率为３８．１０％，较消融前明显降低。结论右心房后下部组织是ＡＶＮＲＴ和ＡＦＬ折返环路的共同部分，慢径是右心房后下部缓慢传导组织向房室结     

射频消融房室结慢径治疗房室结折返性心动过速消融终点的探讨

消融房室结慢径是治疗房室结折返性心动过速（AVNRT）安全而有效的方法.但AVNRT消融终点标准意见不尽一致.本文分析163例AVNRT的射频导管消融术（RFCA）电生理特征及慢径消融时的心电改变,并对其消融的终点标准、消融方法学及并发症预防进行探讨.     

房室结慢径消融治疗房室结折返性心动过速并发完全性房室阻滞的研究

<正> 射频消融(Radiofrequency current ablation,RFCA)治疗房室结折返性心动过速(AVNRT)临床上已得到广泛开展,选择性消融慢径被一致认为是最安全、有效的方法.但有部分患者并发完全性房室传导阻滞,即使在有经验的心脏中心,其发生率仍为0～3%,可发生在消融过程中,亦可发生在消融术后.我们对我院开展RFCA工作以来发生的2例完全性房室传导阻滞病例进行了回顾分析,以避免今后发生完全性房室传导阻滞等并发症.1 资料和方法病例:对56例AVNRT病人进行了房室结慢径消融,其中2例出现Ⅲ°房室传导阻滞,均为男性,年龄分别为63岁、32岁,阵发性室上性心动过速病史超过十年,既往无器质性心脏病和传导阻滞病史.     

房室结慢径区域消融对迷走神经功能及心房颤动易感性的影响

目的心房颤动（房颤）与房室结折返性心动过速有着某种程度的关联性,慢径区域消融可能影响了心房自主神经功能而导致窦性心动过速。但慢径区消融对心房自主神经功能的具体影响目前尚不清楚。本文旨在探讨慢径区消融对心房迷走神经调节功能及房颤易感性的影响。方法11条成年杂种犬,全身麻醉下行颈交感一迷走神经干剥离术。经右颈内静脉穿刺放置冠状静脉窦导管,经左股静脉穿刺放置右心室导管及右心房标测电极导管（Halo导管）,经右股静脉穿刺放置消融导管和希氏束导管。静脉应用美托洛尔阻断交感神经活性。测量慢径区域消融前后基础状态及迷走神经刺激下的窦性周长（SCL）及高位右心房（HRA）、低位右心房（IRA）、冠状静脉窦近端（CSp）和冠状静脉窦远端（CSd）的有效不应期（ERP）及心房易感窗口（VW）。结果（1）SCL的变化：消融前后迷走神经刺激导致的SCL缩短值无明显改变[（107±19）次／min对（108±8）次／min,P〉0．05],提示慢径区域消融没有明显改变迷走神经对窦房结的调节作用。（2）ERP的变化：消融前后迷走神经刺激导致的ERP缩短值在HRA分别为[（69±37）ms对（55±34）ms,P〉0．05],CSd分别为[（55±30）ms对（42±32）ms,P=0．08],IRA分别为[（66±24）ms对（19±21）ms,P〈0．001],CSp分别为[（46±24）ms对（7±18）ms,P〈0．001]。提示慢径区域消融对HRA及窦房结区域的迷走神经调节功能无明显影响,对CSd区域的迷走神经调节功能有一定的影响,而导致了IRA及CSp区域去迷走神经效应。（3）心房VW的变化：消融前后基础状态下各个部位刺激均较难诱发房颤（VW接近0）。消融后,HRA迷走神经刺激诱发房颤的能力较消融前没有明显变化[（63±31）ms对（63±25）ms,P〉0．05],CSd的VW有一定程度的降低[（35±37）ms对（57±28）ms,P     

射频消融房室结慢径对房室结传导功能的电生理影响

58例射频消融(RFCA)房室结慢径对房室结传导功能的电生理影响 结果 RFCA后房室结正向1:1传导的最短周期延长、快径前传有效不应期缩短,慢径前传有效不应期无明显改变,不影响房室结传导功能。     

房室结慢径区域消融对迷走神经功能及心房颤动易感性的影响

Objective Atrioventricular node reentrant tachycardia (AVNRT) ablation may effect the vagal response,which is indicated by sinus tachycardia. On the other hand,atrial fibrillation (AF) ,which was found to be associated with vagal irmervation, often coexists with AVNRT. However,little is known about the im-pact of slow pathway ablation on local vagal innervation to atria. Methods In 11 dogs, bilateral cervical sympa-thovagal trunks were decentralized and metoprolol was given to block sympathetic effects. Linear lesion was per-formed from coronary sinus (CS) ostium to the middle area of Koch triangle. Atrial effective refractory period(ERP) ,vulnerability window (VW) of AF, and sinus rhythm cycle length (SCL) were measured at high fight atrium (HRA),low right atrium (LRA), distal (CSd) and proximal CS (CSp) at baseline with and without vagal stimulation before and after ablation. The histological study was also performed. Results (1) SCL during vagal stimulation remained unchanged before and after ablation(107±19)bpm vs (108±8) bpm (P > 0.05). (2) After ablation, ERP during vagal stimulation remained unchanged at HRA (55±34) ms vs (69 ±37) ms (P >0.05),and decreased slightly at CSd (42±32) ms vs (55±30) ms (P =0.08). However,at LRA and CSp,ERP was significantly decreased after ablation (19±21) ms vs (66±24) ms (P <0.001) ; and (7± 18) ms vs (46±24) ms (P < 0.001), respectively. (3) AF was difficult to be induced at baseline before and after ablation in all sites (VW close to 0). While during vagal stimulation, after ablation VW of AF significantly decreased at LRA (1±3) ms vs (49±36) ms (P < 0.005) and CSp (10±12) ms vs (45±34) ms (P < 0.05) ,decreased slightly at CSd after ablation (35±37) ms vs (57±28) ms (P =0.07) ,and remained un-changed at HRA (63±31) ms vs (63±25) ms (P > 0.05). (4) The altered architecture of individual gan-glia was histologically observed. Conclusions The decreased ERP shortening to vagal stimulation in CS and LRA induced by slow pathway ablation indicates that ablation in such area may result in the vagal dennervation in LRA and CS,thereby attenuating the susceptibility to vagal mediated AF. While unchanged SCL,ERP short-ening and VW to vagal stimulation in sinus node area and HRA indicate that slow pathway ablation did not change the vagal innervation to these sites.     

房室结慢径区域消融对迷走神经功能及心房颤动易感性的影响

Objective Atrioventricular node reentrant tachycardia (AVNRT) ablation may effect the vagal response,which is indicated by sinus tachycardia. On the other hand,atrial fibrillation (AF) ,which was found to be associated with vagal irmervation, often coexists with AVNRT. However,little is known about the im-pact of slow pathway ablation on local vagal innervation to atria. Methods In 11 dogs, bilateral cervical sympa-thovagal trunks were decentralized and metoprolol was given to block sympathetic effects. Linear lesion was per-formed from coronary sinus (CS) ostium to the middle area of Koch triangle. Atrial effective refractory period(ERP) ,vulnerability window (VW) of AF, and sinus rhythm cycle length (SCL) were measured at high fight atrium (HRA),low right atrium (LRA), distal (CSd) and proximal CS (CSp) at baseline with and without vagal stimulation before and after ablation. The histological study was also performed. Results (1) SCL during vagal stimulation remained unchanged before and after ablation(107±19)bpm vs (108±8) bpm (P > 0.05). (2) After ablation, ERP during vagal stimulation remained unchanged at HRA (55±34) ms vs (69 ±37) ms (P >0.05),and decreased slightly at CSd (42±32) ms vs (55±30) ms (P =0.08). However,at LRA and CSp,ERP was significantly decreased after ablation (19±21) ms vs (66±24) ms (P <0.001) ; and (7± 18) ms vs (46±24) ms (P < 0.001), respectively. (3) AF was difficult to be induced at baseline before and after ablation in all sites (VW close to 0). While during vagal stimulation, after ablation VW of AF significantly decreased at LRA (1±3) ms vs (49±36) ms (P < 0.005) and CSp (10±12) ms vs (45±34) ms (P < 0.05) ,decreased slightly at CSd after ablation (35±37) ms vs (57±28) ms (P =0.07) ,and remained un-changed at HRA (63±31) ms vs (63±25) ms (P > 0.05). (4) The altered architecture of individual gan-glia was histologically observed. Conclusions The decreased ERP shortening to vagal stimulation in CS and LRA induced by slow pathway ablation indicates that ablation in such area may result in the vagal dennervation in LRA and CS,thereby attenuating the susceptibility to vagal mediated AF. While unchanged SCL,ERP short-ening and VW to vagal stimulation in sinus node area and HRA indicate that slow pathway ablation did not change the vagal innervation to these sites.     

房室结慢径区域消融对迷走神经功能及心房颤动易感性的影响

Objective Atrioventricular node reentrant tachycardia (AVNRT) ablation may effect the vagal response,which is indicated by sinus tachycardia. On the other hand,atrial fibrillation (AF) ,which was found to be associated with vagal irmervation, often coexists with AVNRT. However,little is known about the im-pact of slow pathway ablation on local vagal innervation to atria. Methods In 11 dogs, bilateral cervical sympa-thovagal trunks were decentralized and metoprolol was given to block sympathetic effects. Linear lesion was per-formed from coronary sinus (CS) ostium to the middle area of Koch triangle. Atrial effective refractory period(ERP) ,vulnerability window (VW) of AF, and sinus rhythm cycle length (SCL) were measured at high fight atrium (HRA),low right atrium (LRA), distal (CSd) and proximal CS (CSp) at baseline with and without vagal stimulation before and after ablation. The histological study was also performed. Results (1) SCL during vagal stimulation remained unchanged before and after ablation(107±19)bpm vs (108±8) bpm (P > 0.05). (2) After ablation, ERP during vagal stimulation remained unchanged at HRA (55±34) ms vs (69 ±37) ms (P >0.05),and decreased slightly at CSd (42±32) ms vs (55±30) ms (P =0.08). However,at LRA and CSp,ERP was significantly decreased after ablation (19±21) ms vs (66±24) ms (P <0.001) ; and (7± 18) ms vs (46±24) ms (P < 0.001), respectively. (3) AF was difficult to be induced at baseline before and after ablation in all sites (VW close to 0). While during vagal stimulation, after ablation VW of AF significantly decreased at LRA (1±3) ms vs (49±36) ms (P < 0.005) and CSp (10±12) ms vs (45±34) ms (P < 0.05) ,decreased slightly at CSd after ablation (35±37) ms vs (57±28) ms (P =0.07) ,and remained un-changed at HRA (63±31) ms vs (63±25) ms (P > 0.05). (4) The altered architecture of individual gan-glia was histologically observed. Conclusions The decreased ERP shortening to vagal stimulation in CS and LRA induced by slow pathway ablation indicates that ablation in such area may result in the vagal dennervation in LRA and CS,thereby attenuating the susceptibility to vagal mediated AF. While unchanged SCL,ERP short-ening and VW to vagal stimulation in sinus node area and HRA indicate that slow pathway ablation did not change the vagal innervation to these sites.     

房室结慢径区域消融对迷走神经功能及心房颤动易感性的影响

Objective Atrioventricular node reentrant tachycardia (AVNRT) ablation may effect the vagal response,which is indicated by sinus tachycardia. On the other hand,atrial fibrillation (AF) ,which was found to be associated with vagal irmervation, often coexists with AVNRT. However,little is known about the im-pact of slow pathway ablation on local vagal innervation to atria. Methods In 11 dogs, bilateral cervical sympa-thovagal trunks were decentralized and metoprolol was given to block sympathetic effects. Linear lesion was per-formed from coronary sinus (CS) ostium to the middle area of Koch triangle. Atrial effective refractory period(ERP) ,vulnerability window (VW) of AF, and sinus rhythm cycle length (SCL) were measured at high fight atrium (HRA),low right atrium (LRA), distal (CSd) and proximal CS (CSp) at baseline with and without vagal stimulation before and after ablation. The histological study was also performed. Results (1) SCL during vagal stimulation remained unchanged before and after ablation(107±19)bpm vs (108±8) bpm (P > 0.05). (2) After ablation, ERP during vagal stimulation remained unchanged at HRA (55±34) ms vs (69 ±37) ms (P >0.05),and decreased slightly at CSd (42±32) ms vs (55±30) ms (P =0.08). However,at LRA and CSp,ERP was significantly decreased after ablation (19±21) ms vs (66±24) ms (P <0.001) ; and (7± 18) ms vs (46±24) ms (P < 0.001), respectively. (3) AF was difficult to be induced at baseline before and after ablation in all sites (VW close to 0). While during vagal stimulation, after ablation VW of AF significantly decreased at LRA (1±3) ms vs (49±36) ms (P < 0.005) and CSp (10±12) ms vs (45±34) ms (P < 0.05) ,decreased slightly at CSd after ablation (35±37) ms vs (57±28) ms (P =0.07) ,and remained un-changed at HRA (63±31) ms vs (63±25) ms (P > 0.05). (4) The altered architecture of individual gan-glia was histologically observed. Conclusions The decreased ERP shortening to vagal stimulation in CS and LRA induced by slow pathway ablation indicates that ablation in such area may result in the vagal dennervation in LRA and CS,thereby attenuating the susceptibility to vagal mediated AF. While unchanged SCL,ERP short-ening and VW to vagal stimulation in sinus node area and HRA indicate that slow pathway ablation did not change the vagal innervation to these sites.     

房室结慢径区域消融对迷走神经功能及心房颤动易感性的影响

Objective Atrioventricular node reentrant tachycardia (AVNRT) ablation may effect the vagal response,which is indicated by sinus tachycardia. On the other hand,atrial fibrillation (AF) ,which was found to be associated with vagal irmervation, often coexists with AVNRT. However,little is known about the im-pact of slow pathway ablation on local vagal innervation to atria. Methods In 11 dogs, bilateral cervical sympa-thovagal trunks were decentralized and metoprolol was given to block sympathetic effects. Linear lesion was per-formed from coronary sinus (CS) ostium to the middle area of Koch triangle. Atrial effective refractory period(ERP) ,vulnerability window (VW) of AF, and sinus rhythm cycle length (SCL) were measured at high fight atrium (HRA),low right atrium (LRA), distal (CSd) and proximal CS (CSp) at baseline with and without vagal stimulation before and after ablation. The histological study was also performed. Results (1) SCL during vagal stimulation remained unchanged before and after ablation(107±19)bpm vs (108±8) bpm (P > 0.05). (2) After ablation, ERP during vagal stimulation remained unchanged at HRA (55±34) ms vs (69 ±37) ms (P >0.05),and decreased slightly at CSd (42±32) ms vs (55±30) ms (P =0.08). However,at LRA and CSp,ERP was significantly decreased after ablation (19±21) ms vs (66±24) ms (P <0.001) ; and (7± 18) ms vs (46±24) ms (P < 0.001), respectively. (3) AF was difficult to be induced at baseline before and after ablation in all sites (VW close to 0). While during vagal stimulation, after ablation VW of AF significantly decreased at LRA (1±3) ms vs (49±36) ms (P < 0.005) and CSp (10±12) ms vs (45±34) ms (P < 0.05) ,decreased slightly at CSd after ablation (35±37) ms vs (57±28) ms (P =0.07) ,and remained un-changed at HRA (63±31) ms vs (63±25) ms (P > 0.05). (4) The altered architecture of individual gan-glia was histologically observed. Conclusions The decreased ERP shortening to vagal stimulation in CS and LRA induced by slow pathway ablation indicates that ablation in such area may result in the vagal dennervation in LRA and CS,thereby attenuating the susceptibility to vagal mediated AF. While unchanged SCL,ERP short-ening and VW to vagal stimulation in sinus node area and HRA indicate that slow pathway ablation did not change the vagal innervation to these sites.     

房室结慢径区域消融对迷走神经功能及心房颤动易感性的影响

Objective Atrioventricular node reentrant tachycardia (AVNRT) ablation may effect the vagal response,which is indicated by sinus tachycardia. On the other hand,atrial fibrillation (AF) ,which was found to be associated with vagal irmervation, often coexists with AVNRT. However,little is known about the im-pact of slow pathway ablation on local vagal innervation to atria. Methods In 11 dogs, bilateral cervical sympa-thovagal trunks were decentralized and metoprolol was given to block sympathetic effects. Linear lesion was per-formed from coronary sinus (CS) ostium to the middle area of Koch triangle. Atrial effective refractory period(ERP) ,vulnerability window (VW) of AF, and sinus rhythm cycle length (SCL) were measured at high fight atrium (HRA),low right atrium (LRA), distal (CSd) and proximal CS (CSp) at baseline with and without vagal stimulation before and after ablation. The histological study was also performed. Results (1) SCL during vagal stimulation remained unchanged before and after ablation(107±19)bpm vs (108±8) bpm (P > 0.05). (2) After ablation, ERP during vagal stimulation remained unchanged at HRA (55±34) ms vs (69 ±37) ms (P >0.05),and decreased slightly at CSd (42±32) ms vs (55±30) ms (P =0.08). However,at LRA and CSp,ERP was significantly decreased after ablation (19±21) ms vs (66±24) ms (P <0.001) ; and (7± 18) ms vs (46±24) ms (P < 0.001), respectively. (3) AF was difficult to be induced at baseline before and after ablation in all sites (VW close to 0). While during vagal stimulation, after ablation VW of AF significantly decreased at LRA (1±3) ms vs (49±36) ms (P < 0.005) and CSp (10±12) ms vs (45±34) ms (P < 0.05) ,decreased slightly at CSd after ablation (35±37) ms vs (57±28) ms (P =0.07) ,and remained un-changed at HRA (63±31) ms vs (63±25) ms (P > 0.05). (4) The altered architecture of individual gan-glia was histologically observed. Conclusions The decreased ERP shortening to vagal stimulation in CS and LRA induced by slow pathway ablation indicates that ablation in such area may result in the vagal dennervation in LRA and CS,thereby attenuating the susceptibility to vagal mediated AF. While unchanged SCL,ERP short-ening and VW to vagal stimulation in sinus node area and HRA indicate that slow pathway ablation did not change the vagal innervation to these sites.     

房室结慢径区域消融对迷走神经功能及心房颤动易感性的影响

Objective Atrioventricular node reentrant tachycardia (AVNRT) ablation may effect the vagal response,which is indicated by sinus tachycardia. On the other hand,atrial fibrillation (AF) ,which was found to be associated with vagal irmervation, often coexists with AVNRT. However,little is known about the im-pact of slow pathway ablation on local vagal innervation to atria. Methods In 11 dogs, bilateral cervical sympa-thovagal trunks were decentralized and metoprolol was given to block sympathetic effects. Linear lesion was per-formed from coronary sinus (CS) ostium to the middle area of Koch triangle. Atrial effective refractory period(ERP) ,vulnerability window (VW) of AF, and sinus rhythm cycle length (SCL) were measured at high fight atrium (HRA),low right atrium (LRA), distal (CSd) and proximal CS (CSp) at baseline with and without vagal stimulation before and after ablation. The histological study was also performed. Results (1) SCL during vagal stimulation remained unchanged before and after ablation(107±19)bpm vs (108±8) bpm (P > 0.05). (2) After ablation, ERP during vagal stimulation remained unchanged at HRA (55±34) ms vs (69 ±37) ms (P >0.05),and decreased slightly at CSd (42±32) ms vs (55±30) ms (P =0.08). However,at LRA and CSp,ERP was significantly decreased after ablation (19±21) ms vs (66±24) ms (P <0.001) ; and (7± 18) ms vs (46±24) ms (P < 0.001), respectively. (3) AF was difficult to be induced at baseline before and after ablation in all sites (VW close to 0). While during vagal stimulation, after ablation VW of AF significantly decreased at LRA (1±3) ms vs (49±36) ms (P < 0.005) and CSp (10±12) ms vs (45±34) ms (P < 0.05) ,decreased slightly at CSd after ablation (35±37) ms vs (57±28) ms (P =0.07) ,and remained un-changed at HRA (63±31) ms vs (63±25) ms (P > 0.05). (4) The altered architecture of individual gan-glia was histologically observed. Conclusions The decreased ERP shortening to vagal stimulation in CS and LRA induced by slow pathway ablation indicates that ablation in such area may result in the vagal dennervation in LRA and CS,thereby attenuating the susceptibility to vagal mediated AF. While unchanged SCL,ERP short-ening and VW to vagal stimulation in sinus node area and HRA indicate that slow pathway ablation did not change the vagal innervation to these sites.     

房室结慢径区域消融对迷走神经功能及心房颤动易感性的影响

Objective Atrioventricular node reentrant tachycardia (AVNRT) ablation may effect the vagal response,which is indicated by sinus tachycardia. On the other hand,atrial fibrillation (AF) ,which was found to be associated with vagal irmervation, often coexists with AVNRT. However,little is known about the im-pact of slow pathway ablation on local vagal innervation to atria. Methods In 11 dogs, bilateral cervical sympa-thovagal trunks were decentralized and metoprolol was given to block sympathetic effects. Linear lesion was per-formed from coronary sinus (CS) ostium to the middle area of Koch triangle. Atrial effective refractory period(ERP) ,vulnerability window (VW) of AF, and sinus rhythm cycle length (SCL) were measured at high fight atrium (HRA),low right atrium (LRA), distal (CSd) and proximal CS (CSp) at baseline with and without vagal stimulation before and after ablation. The histological study was also performed. Results (1) SCL during vagal stimulation remained unchanged before and after ablation(107±19)bpm vs (108±8) bpm (P > 0.05). (2) After ablation, ERP during vagal stimulation remained unchanged at HRA (55±34) ms vs (69 ±37) ms (P >0.05),and decreased slightly at CSd (42±32) ms vs (55±30) ms (P =0.08). However,at LRA and CSp,ERP was significantly decreased after ablation (19±21) ms vs (66±24) ms (P <0.001) ; and (7± 18) ms vs (46±24) ms (P < 0.001), respectively. (3) AF was difficult to be induced at baseline before and after ablation in all sites (VW close to 0). While during vagal stimulation, after ablation VW of AF significantly decreased at LRA (1±3) ms vs (49±36) ms (P < 0.005) and CSp (10±12) ms vs (45±34) ms (P < 0.05) ,decreased slightly at CSd after ablation (35±37) ms vs (57±28) ms (P =0.07) ,and remained un-changed at HRA (63±31) ms vs (63±25) ms (P > 0.05). (4) The altered architecture of individual gan-glia was histologically observed. Conclusions The decreased ERP shortening to vagal stimulation in CS and LRA induced by slow pathway ablation indicates that ablation in such area may result in the vagal dennervation in LRA and CS,thereby attenuating the susceptibility to vagal mediated AF. While unchanged SCL,ERP short-ening and VW to vagal stimulation in sinus node area and HRA indicate that slow pathway ablation did not change the vagal innervation to these sites.