Purpose

To evaluate nature of AV nodal activation in patients with AVNRT using high density electro-anatomic mapping (HD-EAM).

Methods

HD-EAM was created in 30 patients with AVNRT from the triangle of Koch (ToK) in sinus rhythm (SR). Isochronal late activation maps (ILAM) were created. EAMs were analyzed for slow pathway (SPW) and fast pathway (FPW) activation. A pivot point (PP) was defined where FPW and SPW collided and pivoted back to the AV node (AVN). Conduction was assessed with programmed extrastimulus (PES) in 9 patients until FPW refractory period (ERP). The change in PP distance from the HIS (ΔPP) was measured in SR and PES. The ΔPP was compared to ΔAH. The PP was ablated and SR re-mapped.

Results

The FPW activates the His and moves inferiorly toward the coronary sinus (CS). Activation also enters the ToK near the CS and collides with the FPW which then pivots around a functional line of block (LOB) within the ToK and moves superiorly along the septal tricuspid annulus. PP electrograms are fractionated, low amplitude, and consistent with SPW potentials (Haissaguerre et al. in Circulation 85:2162–2175, 1992). During PES the PP moved superiorly until FPW ERP when only SPW activation occurs. Normalized ΔAH and ΔPR vs ΔPP was highly correlated p < 0.0001. Ablation at the PP was successful and associated with loss of SPW fusion and pivot.

Conclusion

We conclude HD-EAM/ILAM provide a novel method for localizing the SPW in SR. This study provides further understanding of dual AV nodal physiology and may aid in targeting the SPW for ablation of AVNRT.

中文翻译：

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窦性心律期间慢通路传导的生理学：来自 Koch 三角内高密度映射的证据

目的

使用高密度电解剖标测 (HD-EAM) 评估 AVNRT 患者 AV 结激活的性质。

方法

HD-EAM 是在 30 名窦性心律 (SR) 中来自 Koch 三角 (ToK) 的 AVNRT 患者中创建的。创建了等时延迟激活图 (ILAM)。分析 EAM 的慢通路 (SPW) 和快通路 (FPW) 激活。在 FPW 和 SPW 碰撞并转回 AV 节点 (AVN) 的地方定义了一个枢轴点 (PP)。9 名患者在 FPW 不应期 (ERP) 之前使用程序性额外刺激 (PES) 评估传导。在 SR 和 PES 中测量 PP 与 HIS 的距离 (ΔPP) 的变化。将 ΔPP 与 ΔAH 进行比较。PP 被烧蚀并重新映射 SR。

结果

FPW 激活 His 并向下向冠状窦 (CS) 移动。激活也进入 CS 附近的 ToK 并与 FPW 碰撞，FPW 然后围绕 ToK 内的功能阻滞线 (LOB) 旋转并沿三尖瓣环向上移动。PP 电图是分级的、低幅度的，并且与 SPW 电位一致（Haissaguerre 等人在 Circulation 85:2162–2175, 1992 中）。在 PES 期间，PP 向上移动直到 FPW ERP，此时仅发生 SPW 激活。归一化的 ΔAH 和 ΔPR 与 ΔPP 高度相关p  < 0.0001。PP 的消融是成功的，并且与 SPW 融合和枢轴的丧失有关。

结论

我们得出结论，HD-EAM/ILAM 提供了一种在 SR 中定位 SPW 的新方法。这项研究提供了对双 AV 结生理学的进一步理解，并可能有助于靶向 SPW 以消融 AVNRT。