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.     

右室不同部位起搏的急性血流动力学效应比较

[目的]比较右室不同部位起搏的急性血流动力学效应,进一步明确最佳心室起搏部位。[方法]入选完全性房室传导阻滞患者47例。随机分为两组:A组(24例)植入临时起搏电极至右室心尖部组,B组(23例)植入临时起搏电极至右室流出道,其后两组患者均植入永久起搏电极至右室高位间隔部。比较不同部位起搏下的每搏量(SV)、左室舒张末期直径(LV)、左室射血分数(LVEF)、左房内径(LA)以及QRS波时限的差异。[结果]右室流出道与心尖部起搏比较,LVEF和SV值略有改善P=0.071,P=0.043,LVD和LAD,以及QRS波时限变化不大。高位间隔和右室心尖部起搏比较,LVEF值、SV以及QRS波时限明显改善,P值分别为0.007和0.002以及P<0.001;LVD和LAD无变化。高位间隔和右室流出道起搏比较,LVEF值和SV以及QRS波时限有所改善,P值分别为0.017和0.014,以及P<0.001;LVD和LAD无变化。[结论]高位间隔起搏明显优于流出道和心尖部起搏。而流出道起搏略优于心尖部起搏。     

房颤患者消融后疾病感知在心脏康复与健康行为间的中介效应

目的 探讨疾病感知在房颤患者消融术后心脏康复与健康行为间的作用机制,为提高房颤患者消融术后的生活质量提供参考。方法 于2019年9月至2020年1月采用一般情况调查表、心脏康复量表、疾病感知问卷及健康生活方式量表,对辽宁省某三级甲等医院的260例行消融术后的房颤患者进行调查。结果 心脏康复与健康促进行为呈正相关(r=0.522;P<0.01),疾病感知与心脏康复、健康行为呈负相关(r=-0.263,-0.540;P<0.01);通过结构方程模型显示,心脏康复对健康促进行为直接效应不显著(β=0.232,P>0.05),疾病感知在心脏康复与健康行为间起完全中介作用(β=0.527,P<0.05),中介效应占总效应(β=0.759,P<0.05)的69.43%。结论 疾病感知是房颤患者消融术后心脏康复与健康行为间的中介变量,医务人员应该关注房颤患者消融术后的疾病感知水平,对患者进行正确的知识宣教,提高对疾病的正确认知,以便提高患者的心脏康复及依从性,采取正确的康复手段,有效地提高患者的术后生活质量。     

迷走神经对心房电生理的修饰作用

支配心脏的副交感神经起源于延髓的背侧运动核~([1-2]),发出节前纤维构成迷走神经主干,自颈静脉孔出颅后沿颈部下行,经胸上口入胸腔,发出心支至心丛,并在此处交换神经元.迷走神经节后纤维释放的递质主要是乙酰胆碱,可以和心肌细胞上的M2受体结合,与Gi和Gk蛋白耦联.     

迷走神经活动对心房电重构的影响

目的 研究迷走神经干预对心房电重构的影响.方法 24只杂种犬随机分为3组,为排除交感神经对心房电重构的影响,3组犬均应用美托洛尔阻断交感神经效应.A组10只犬快速心房起搏过程中无迷走神经干预,B组8只犬应用阿托品阻断迷走神经效应,C组6只犬在快速心房起搏过程中同时进行迷走神经刺激.在右心房(RA)、冠状静脉窦(CS)和右心室(RV)放置多极导管.通过RA电极导管进行600次/min心房起搏30 min构建急性心房电重构模型.在右心房快速起搏前后测量基础状态(无迷走神经刺激)和迷走神经刺激下的心房有效不应期(AERP)和心房颤动(房颤)易感窗口(VW).结果 A组犬右心房快速起搏后基础状态下及迷走神经刺激时的AERP较起搏前明显缩短(P＜0.05).B组犬右心房快速起搏后基础状态下及迷走神经刺激时的AERP较起搏前无明显变化(P＞0.05).C组犬右心房快速起搏后基础状态下及迷走神经刺激时的AERP较起搏前明显缩短(P＜0.05).A组及C组右心房快速起搏后AERP缩短值明显大于B组(P＜0.05),但A组及C组AERP缩短值差异无统计学意义(P＞0.05).迷走神经刺激下,B组犬在右心房快速起搏前后均较难诱发房颤(VW接近0),A组及C组犬右心房快速起搏后较起搏前容易诱发房颤(P＜0.05).结论 短期右心房快速起搏导致的心房电重构过程中伴随着迷走神经兴奋性增强.迷走神经兴奋性增强及迷走神经刺激加重心房电重构,导致房颤易感性增加.迷走神经阻滞能减轻心房电重构,降低房颤易感性.     

心房不同部位刺激在显示肺静脉电位中的作用

目的研究不同部位心房刺激在术中清晰准确地显示肺静脉电位(pulmonary vein potential,PVP)的作用. 方法(1)病例选择:44例行射频消融术的房颤患者,症状明显;发作频繁;药物治疗效果不佳;无器质性心脏病,男性34例,女性10例,年龄(52±11)岁,病史(7±5)年.     

心房反复激动与阵发性心房颤动关系的实验研究

目的使用单相动作电位技术(MAP)对在体犬左、右心房肌的电学特性进行研究,以探讨阵发性心房颤动(房颤)的发生与维持机制.     

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.     

心房颤动基质的研究进展

心房颤动的射频导管消融术已经成为心房颤动的重要治疗手段。目前阵发性心房颤动的术后成功率在70%~80%,持续性心房颤动和长程持续性心房颤动的手术成功率在40%~80%。非阵发性心房颤动的手术成功率较阵发性心房颤动明显偏低,主要原因在于其机制复杂,尤其除肺静脉驱动外导致心房颤动长期维持的机制,即心房基质的本质并不明了,评价和干预这些基质的手段也不明确。现对心房颤动基质的研究进展,以及相应的消融策略做一综述。     

华法林在低栓塞风险的心房颤动患者射频消融术后的应用

目的探讨消融治疗获得成功的持续性心房颤动患者,特别是栓塞风险低的个体,术后是否需要继续应用华法林抗凝治疗。方法入选低危栓塞风险的持续性心房颤动患者107例,射频消融术后随机分为华法林治疗组(55例)和非华法林组(52例),华法林治疗组患者术后服用华法林治疗至少3个月,抗凝治疗强度为INR2.0～3.0;非华法林组只服用阿司匹林,每日100mg。所有患者术后均进行随访,观察比较两组患者血栓栓塞和出血事件发生率的差异。结果所有患者均成功完成射频消融术,即刻成功率为100%。两组患者术中均未发生栓塞或出血事件。随访6～18个月,华法林组发生血栓栓塞事件2例(3.6%),非华法林组发生2例(3.7%),两组患者栓塞发生率无统计学差异,P>0.1。华法林组有3例(5.5%)出血事件,非华法林组无出血事件发生。结论对于射频消融取得成功的低危心房颤动患者,可以考虑不应用华法林抗凝,而只服用阿司匹林。