Kowey P R, Friehling T D, Wetstein L, O'Connor K M, Kelliher G J
Am J Cardiol. 1984 Aug 1;54(3):421-3. doi: 10.1016/0002-9149(84)90209-1.
Site of stimulation is an important variable in the inducibility of ventricular tachycardia in both non-human animal infarction models and in humans; that is, proximity of the stimulating electrode to the site of reentry facilitates the induction of sustained arrhythmia. Whether site of stimulation is decisive in measurement of vulnerability to ventricular fibrillation (VF) during acute coronary occlusion has not been fully evaluated. We measured VF thresholds in 9 chloralose-anesthetized cats at 2 right ventricular and 3 left ventricular sites (2 endocardial, 3 intramural) before and after abrupt occlusion of the anterior descending coronary artery. VF thresholds were measured using a single stimulus of increasing intensity delivered during ventricular drive. Although VF thresholds were lower at endocardial sites, there were no significant differences in VF threshold among any of the sites tested at control. After occlusion, VF thresholds fell to a similar extent at all 5 sites tested. The percent reduction in VF threshold at any site was not influenced by the sequence of testing. VF may be precipitated from multiple sites and, unlike ventricular tachycardia, does not represent an isolated focus of arrhythmogenicity.
在非人类动物梗死模型和人类中，刺激部位是室性心动过速诱导性的一个重要变量；也就是说，刺激电极与折返部位的接近程度有助于诱发持续性心律失常。在急性冠状动脉闭塞期间，刺激部位在心室颤动（VF）易损性测量中是否起决定性作用尚未得到充分评估。我们在9只水合氯醛麻醉的猫身上，于冠状动脉前降支突然闭塞前后，在右心室的2个部位和左心室的3个部位（2个心内膜部位、3个壁内部位）测量了VF阈值。VF阈值是通过在心室起搏期间给予强度递增的单个刺激来测量的。尽管心内膜部位的VF阈值较低，但在对照时所测试的任何部位之间，VF阈值均无显著差异。闭塞后，所有5个测试部位的VF阈值下降程度相似。任何部位VF阈值的降低百分比不受测试顺序的影响。VF可能从多个部位诱发，并且与室性心动过速不同，它并不代表一个孤立的致心律失常灶。
