Mechanisms and pharmacological control of ventricular spiral-wave reentry

心室螺旋波折返的机制和药理控制

• 批准号: 12470150
• 负责人: KODAMA Itsuo
• 金额: $ 10.69万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12470150/
• 关键词: Spiral reentry; Optical mapping; Ventricular tachycardia; Action potential; Anisotropic conduction; Curvature effect; Block line; 不整脈; スパイラルリエントリー; 異方性興奮伝導; 高速度ビデオカメラ; イオンチャネル; 不整脈薬物治療

We have analyzed dynamics of spiral-wave reentry in rabbit hearts perfused in-vitro using our original optical mapping system with a high spatio-temporal resolution.1. Development of a new optical mapping system using a high-speed digital video camera combined with light-emitting diodes.This system has an advantage over ones reported previously by other investigators in terms of high spatio-temporal resolutions (0.1 mm and 1.3 ms) and signal quality (S/N ratio 10.6) combined with less photo-bleaching (2.4%/min), and this system enables us to analyze the detail of the spiral-wave dynamics during cardiac tachyarrhythmias.2. Analysis of ventricular spiral dynamicsDynamics and pharmacological modulation of spiral reentry during ventricular tachycardia (VT) was investigated in a two-dimensional anisotropic subepicardial layer of rabbit ventricular myocardium by use of our original high-resolution optical mapping system. VT induced by cross-field stimulation was often caused by single-loop r … More eentry around a functional line of block. The functional block line was formed by meandering of the spiral tip along its own refractory tail (refractory block line) combined with pronounced conduction delay at the pivot points around the both ends of the central refractory block line (conduction block). The latter was always oriented parallel to the subepicardial fiber direction. There was no isoelectric segment (fully-excitable gap) between action potentials, and low-amplitude double potentials were obtained at the central refractory block line. Blockade of Na^+ channels by pilsicainide or disopyramide markedly enhanced conduction delay at the pivot points resulting in a prolongation of the functional conduction block line. Around the pivot points, the action potentials showed slow upstroke and long duration, but after making a turn, normal action potentials with a short excitable gap were observed. These results suggest that dynamics of two-dimensional ventricular spiral reentry is determined primarily by (1) the curvature of a wavefront, (2) tissue anisotropy and (3) the wavefront-tail interaction. Less

我们已经分析了螺旋波折返的动力学在兔心脏灌注在体外使用我们原来的光学映射系统具有高时空分辨率.开发了一种新型光学测绘系统，该系统使用高速数字摄像机与发光二极管相结合。该系统在高时空分辨率方面比其他研究人员之前报道的系统具有优势（0.1 mm和1.3 ms）和信号质量（信噪比10.6）结合较少的光漂白（2.4%/min），该系统使我们能够分析心动过速时螺旋波动力学的细节.心室螺旋动力学分析利用我们研制的高分辨率光学标测系统，在二维各向异性兔心室肌心外膜下层研究了室性心动过速（VT）时螺旋折返的动力学和药物调制。交叉场刺激诱发的室性心动过速多为单回路心动过速， ...更多信息 围绕功能块行的条目。功能性阻滞线是通过螺旋尖端沿着其自身的不应性尾部（不应性阻滞线）的曲折与围绕中心不应性阻滞线（传导阻滞）两端的枢轴点处的明显传导延迟相结合而形成的。后者始终平行于心外膜纤维方向。动作电位之间没有等电位段（完全可兴奋间隙），在中央不应性阻滞线处获得低振幅双电位。用吡西卡尼或丙吡胺阻断Na^+通道可显著增加中枢点的传导延迟，导致功能性传导阻滞线延长。在枢轴点周围，动作电位表现出缓慢的上升和较长的持续时间，但在转弯后，观察到正常的动作电位和较短的可兴奋间隙。这些结果表明，二维心室螺旋折返的动力学主要由（1）波前曲率，（2）组织各向异性和（3）波前-尾相互作用决定。少

项目成果

本荘晴朗 他: "心室スパイラルリエントリーの成立機構と薬物制御"心臓. 33. 449-455 (2001)

Haruaki Honjo 等：“心室螺旋折返机制和药物控制” Cardiac 33. 449-455 (2001)

Motoki Nihei et al.: "High-resolution optical mapping system with high-speed digital video camera"Environmental Medicine. 45. 103-105 (2001)

Motoki Nihei 等人：“带有高速数字摄像机的高分辨率光学测绘系统”环境医学。

Haruo Honjo et al: "Dynamics and pharmacological control, of ventricular spiral-wave reentry"Shinzo. 33(in Japanese). 449-455 (2001)

Haruo Honjo 等人：“心室螺旋波折返的动力学和药理学控制”Shinzo。

Haruo Honjo et al.: "Blockade of I_<Kr> promotes termination of spiral-type reentrant arrhythmia in the ventricle"Japanese Circulation Journal. 65 (Suppl.I-A). 459 (2001)

Haruo Honjo 等人：“I_<Kr> 的阻断促进心室螺旋型折返性心律失常的终止”日本循环杂志。

荒船龍彦: "高速度DVCRを用いた心筋活動電位マッピング"医用電子と生体工学. 38. 195 (2000)

Tatsuhiko Arafune：“使用高速 DVCR 绘制心肌动作电位”《医疗电子与生物工程》38. 195 (2000)。