摘要
20例杂种麻醉狗同步记录腔内SNE和ECGⅡ,均记到具特征性的P前波(SACT44～68ms)。在电灼希氏束形成房室分离的模型上,于无心室活动的A-A间期里亦成功地记录到P前波。静脉给予异搏定P前波减小或消失。故认为P前波与心室活动无关,也非心房起始波,而是窦房结电位。
In 20 anesthetized dogs intracardiac SNE and ECG Ⅱ were simultaneously recorded ( gain 100uV/cm, time constant 0.3 or 2S, cut off 30Hz ) . Through a A/D convertor the signal to be analysed was fed into APPLE Ⅱ computer system. The Pre-P wave was successfully recorded in all those 20 animals (SACT 44-68ms, amplitude 43-141uV). In of the dogs an electric shock on His-bundle area was induced, which could cause Ⅲ° A-V block. During A-A phase th Pre-P wave could still be recorded. When large dosage of verapamil was administered, the wave disappeared. In other 8 dogs the injection of verapamil ( 250μg/kg, iv. ) reduced Pre-P wave (67.1±29.6 uV). In the other 2 dogs isolated SNP was seen as S-A conduction was blocked by intravenous given KCL. All this shows that the Pre-P wave is sinus node potential but has no relation to ventricular activity.
关键词
窦房结
心电描记术
维拉帕米
狗
: sinoatrial node
electrocardiography
verapamil
dogs
