Yue Arthur M, Franz Michael R, Roberts Paul R, Morgan John M
Wessex Cardiac Center, Southampton General Hospital, Southampton, United Kingdom.
J Am Coll Cardiol. 2005 Sep 20;46(6):1067-75. doi: 10.1016/j.jacc.2005.05.074.
This study was aimed at evaluating global characteristics of electrical restitution in the human ventricle using noncontact mapping.
Steep action potential restitution (slope >1) and conduction velocity (CV) restitution have been linked with propensity to ventricular fibrillation, but clinical measurement of global electrical restitution had not been feasible.
Activation-recovery interval (ARI) and CV restitution curves were simultaneously constructed from 16 regional segments of the left and right ventricles in 8 patients (6 male, 2 female, age 42 +/- 17 years) following successful ablation of idiopathic ventricular tachycardia in the absence of structural disease guided by the Ensite 3000 system (Endocardial Solutions Inc., St. Paul, Minnesota). The ARIs were determined from reconstructed unipolar electrograms as validated with monophasic action potential recordings. The ARI restitution slopes were determined using the overlapping least-squares linear segments.
Global electrical restitution curves were heterogeneous in shape and distribution. ARI restitution slope was >1 at 25% of 128 sites. The overall mean slope was 0.79 and was greater in the left than the right ventricle (0.93 +/- 0.49 vs. 0.65 +/- 0.26, p < 0.001). Dispersion of ARI restitution slopes increased with decreasing diastolic intervals. The CV restitution operated over a narrower range of diastolic intervals compared with ARI restitution, reaching a plateau (10 +/- 6 ms vs. 38 +/- 13 ms, p < 0.001) after refractoriness. The magnitude of CV restitution was also greater (steeper) than ARI restitution (25 +/- 10% vs. 18 +/- 9%, p < 0.001).
Noncontact mapping can be used to examine global electrical restitution in the human ventricle. The ARI restitution is heterogeneous, with a slope >1 at 25% of all sites. The heterogeneity of ARI and CV restitution may be important in determining myocardial electrical stability.
本研究旨在使用非接触式标测评估人体心室电恢复的整体特征。
陡峭的动作电位恢复（斜率>1）和传导速度（CV）恢复与心室颤动倾向有关，但整体电恢复的临床测量尚不可行。
在8例患者（6例男性，2例女性，年龄42±17岁）成功消融特发性室性心动过速后，在无结构性疾病的情况下，使用Ensite 3000系统（Endocardial Solutions公司，明尼苏达州圣保罗）引导，从左心室和右心室的16个区域节段同时构建激活-恢复间隔（ARI）和CV恢复曲线。ARI由重建的单极电图确定，并通过单相动作电位记录进行验证。ARI恢复斜率使用重叠最小二乘线性段确定。
整体电恢复曲线在形状和分布上是异质性的。在128个位点的25%处，ARI恢复斜率>1。总体平均斜率为0.79，左心室大于右心室（0.93±0.49对0.65±0.26，p<0.001）。ARI恢复斜率的离散度随着舒张间期的缩短而增加。与ARI恢复相比，CV恢复在更窄的舒张间期范围内起作用，在不应期后达到平台期（10±6毫秒对38±13毫秒，p<0.001）。CV恢复的幅度也大于（更陡峭）ARI恢复（25±10%对18±9%，p<0.001）。
非接触式标测可用于检查人体心室的整体电恢复。ARI恢复是异质性的，在所有位点的25%处斜率>1。ARI和CV恢复的异质性在确定心肌电稳定性方面可能很重要。
