Hunt G B, Ross D L
Department of Medicine, Westmead Hospital, New South Wales, Australia.
Int J Cardiol. 1990 Sep;28(3):317-24. doi: 10.1016/0167-5273(90)90314-u.
The contribution of left (versus right) ventricular stimulation to the induction of ventricular tachyarrhythmias was studied in 37 dogs with chronic experimental myocardial infarction, and 17 dogs with normal hearts. Programmed stimulation of the endocardium at both ventricular apices employed an aggressive protocol of up to 7 extrastimuli. The right ventricle was the most successful site for induction of ventricular tachycardia after myocardial infarction (74% of dogs with ventricular tachycardia). Ten of 11 animals with slow ventricular tachycardia (greater than or equal to 140 msec) were inducible from the right ventricle. In contrast, left ventricular stimulation was required to induce rapid ventricular tachycardia (cycle length less than 140 msec) in 5 of 10 dogs (P less than 0.05). No animal required more than five extrastimuli from any site for induction of ventricular tachycardia. In the normal heart, ventricular fibrillation was induced most often from the right ventricle (77% of dogs) when compared with the left ventricle (47%, P less than 0.05). Ventricular tachycardia was never induced in normal animals. These results show that the right ventricular apex is the most successful site for induction of "slow" ventricular tachycardia in this canine model when using five extrastimuli. Rapid ventricular tachycardia is frequently induced from the infarcted left ventricle, but this arrhythmia may not be clinically significant. The normal right ventricle is significantly more susceptible to ventricular fibrillation than is the left ventricle, but this does not interfere with induction of ventricular tachycardia in the infarcted heart.
在37只患有慢性实验性心肌梗死的犬和17只心脏正常的犬中，研究了左心室（相对于右心室）刺激对室性快速心律失常诱发的作用。在两个心室尖部进行心内膜程控刺激采用了高达7个期外刺激的激进方案。心肌梗死后，右心室是诱发室性心动过速最成功的部位（74%的室性心动过速犬）。11只患有缓慢室性心动过速（大于或等于140毫秒）的动物中有10只可从右心室诱发。相比之下，10只犬中有5只需要左心室刺激来诱发快速室性心动过速（周期长度小于140毫秒）（P<0.05）。没有动物需要从任何部位接受超过5个期外刺激来诱发室性心动过速。在正常心脏中，与左心室相比，右心室最常诱发心室颤动（77%的犬）（47%，P<0.05）。正常动物从未诱发室性心动过速。这些结果表明，在这个犬类模型中，当使用5个期外刺激时，右心室尖部是诱发“缓慢”室性心动过速最成功的部位。快速室性心动过速常由梗死的左心室诱发，但这种心律失常可能在临床上并不显著。正常右心室比左心室更容易发生心室颤动，但这并不影响梗死心脏中室性心动过速的诱发。
