Department of Medicine, National Yang Ming Chiao Tung University, Hsinchu, Taiwan.
Department of Heart Rhythm Center, Taipei Veterans General Hospital, Taipei, Taiwan.
PLoS One. 2023 Apr 20;18(4):e0282943. doi: 10.1371/journal.pone.0282943. eCollection 2023.
Amiodarone is commonly used during therapeutic hypothermia (TH) following cardiac arrest due to ventricular arrhythmias. However, electrophysiological changes and proarrhythmic risk after amiodarone treatment have not yet been explored in TH.
Epicardial high-density bi-ventricular mapping was performed in pigs under baseline temperature (BT), TH (32-34°C), and amiodarone treatment during TH. The total activation time (TAT), conduction velocity (CV), local electrogram (LE) duration, and wavefront propagation from pre-specified segments were analyzed during sinus rhythm (SR) or right ventricular (RV) pacing (RVP), along with tissue expression of connexin 43. The vulnerability to ventricular arrhythmias was assessed.
Compared to BT, TH increased the global TAT, decreased the CV, and generated heterogeneous electrical substrate during SR and RVP. During TH, the CV reduction and LE duration prolongation were greater in the anterior mid RV than in the other areas, which changed the wavefront propagation in all animals. Compared to TH alone, amiodarone treatment during TH further increased the TAT and LE duration and decreased the CV. Heterogeneous conduction was partially attenuated after amiodarone treatment. After TH and amiodarone treatment, the connexin 43 expression in the anterior mid RV was lower than that in the other areas, compatible with the heterogeneous CV reduction. The animals under TH and amiodarone treatment had a higher incidence of inducible ventricular arrhythmias than those under BT or TH without amiodarone.
Electrical heterogeneity during amiodarone treatment and TH was associated with vulnerability to ventricular arrhythmias.
由于室性心律失常，心脏骤停后常使用胺碘酮进行治疗性低温（TH）。然而，胺碘酮治疗后电生理变化和致心律失常风险在 TH 中尚未得到探索。
在基线温度（BT）、TH（32-34°C）和 TH 期间胺碘酮治疗下，对猪进行心外膜高密度双心室标测。在窦性节律（SR）或右心室（RV）起搏（RVP）期间，分析总激活时间（TAT）、传导速度（CV）、局部电图（LE）持续时间以及来自预定节段的波阵面传播，并分析连接蛋白 43 的组织表达。评估室性心律失常的易感性。
与 BT 相比，TH 在 SR 和 RVP 期间增加了全局 TAT，降低了 CV，并产生了不均匀的电生理基质。在 TH 期间，与其他区域相比，前中 RV 的 CV 降低和 LE 持续时间延长更大，这改变了所有动物的波阵面传播。与单独 TH 相比，TH 期间的胺碘酮治疗进一步增加了 TAT 和 LE 持续时间并降低了 CV。异质性传导在胺碘酮治疗后部分减弱。TH 和胺碘酮治疗后，前中 RV 的连接蛋白 43 表达低于其他区域，与 CV 降低的异质性一致。TH 和胺碘酮治疗下的动物比 BT 或无胺碘酮的 TH 下的动物更容易发生可诱导的室性心律失常。
胺碘酮治疗和 TH 期间的电异质性与室性心律失常的易感性有关。
