Koch 三角解剖与临床.ppt

* * 慢径消融靶点 Quintana：1例AVNRT行慢径消融的患者尸检发现消融线在心房肌?慢径消融时消融的可能是正常心房肌。 慢径消融时避免损伤房室结动脉。Kozlowski：50例人心房室结动脉中，20％位于冠状窦口附近心内膜下。 冠状窦口附近消融及快径消融可消弱迷走神经的支配，导致心脏迷走神经功能下降 起搏标测Koch三角可以发现快径缺如或靠近慢径，从而避免房室传导阻滞 * 慢径消融靶点 影像分区 A区 : A1 A2 M区 : M1 M2 P区 : P1 P2 * 腺苷对房室结双径路的作用 Effects of ATP (20 mg) on AV conduction before （A） and after （B） radiofrequency ablation of the slow pathway * 三、 Koch三角与迷走神经 * Koch三角内迷走神经分布与作用 Koch三角的迷走神经支配主要来自下腔静脉与左房交界处脂肪垫内的迷走神经节团 迷走神经主要支配结细胞 刺激房室结区迷走神经可以减慢房颤心室率 消融慢径可以缩短快径有效不应期 * Koch三角迷走神经分布与作用 Shah：阈下刺激方法证明迷走神经多位于His束下（7/13），也有位于His束和CSO（3/13，3/13） * 临床意义 房颤时房室结的递减性与隐匿性传导导致了慢的和不规则的心室率。 房颤时慢径和快径均参与了传导，慢径前传多于快径前传。故消融慢径可以减慢房颤时的心室率。 消融慢径可以缩短快径有效不应期 刺激房室结区迷走神经可以减慢房颤心室率 * Ventricular Rate Control by Selective Vagal Stimulation IsSuperior to Rhythm Regularization by AtrioventricularNodal Ablation and Pacing During Atrial Fibrillation Selective atrioventricular nodal (AVN) vagal stimulation (AVN-VS) was delivered to the epicardial fat pad that projects parasympathetic nerve fibers to the AVN in 12 dogs during AF. A computer-controlled algorithm adjusted AVN-VS beat by beat to achieve a mean ventricular RR interval of 75%, 100%, 125%, or 150% of spontaneous sinus cycle length. The AVN was then ablated, and the right ventricular (RV) apex was paced either irregularly (i-RVP) using the RR intervals collected during AVN-VS or regularly (r-RVP) at the corresponding mean RR. The results indicated that all 3 strategies improved hemodynamics compared with AF. However, AVN-VS resulted in significantly better responses than either r-RVP or i-RVP. i-RVP resulted in worse hemodynamic responses than r-RVP. The differences among these modes became less significant when mean VR was slowed to 150% of sinus cycle length. Conclusions—AVN-VS can produce graded slowing of the VR during AF wi