内科护理学课件 英语 考试资料dysrhythmias.ppt

Dysrhythmia心律失常 Properties of cardiac tissue 心脏组织的特性 Automaticity 自律性: ability to initiate an impulse spontaneously and continuously. Excitability兴奋性: ability to be electrically stimulated. Contractility收缩性: ability to respond mechanically to an impulse. Conductivity传导性: ability to transmit an impulse along a membrane in an orderly manner. Conduction system: a brief review传导系统 P wave begins with the firing of the SA node and represents depolarization去极化 of the fibers of the atria心房, resulting in atrial contraction心房收缩. The QRS complex represents depolarization去极化 of the ventricles心室, resulting in ventricular contraction心室收缩. The T wave represents repolarization复极of the ventricles心室, or the time at which the ventricles return to the prestimulated state. Conduction system: a brief review Intervals波间隔between these waves reflects the lengths of time it takes for the impulses to travel from one area of the heart to the other. The PR interval represents the period during which the impulse spreads through the atria, AV node房室结, bundle of His希氏束, and Purkinje浦肯野纤维. The QRS interval represents the time it takes for depolarization去极化of both ventricles. The QT interval represents the time it takes for complete depolarization除极and repolarization复极of the ventricles. Dysrhythmia Dysrhythmia is an abnormal cardiac rhythm in terms of the frequency of the impulse频率, rhythm节律, origin site起源部位, conduction velocity传导速度and excitement order激动次序. Classification of Dysrhythmia 心律失常的分类 Abnormal impulse formation 冲动形成异常 sinus dysrhythmia 窦性心律失常 sinus tachycardia窦性心动过速 sinus bradycardia窦性心动过缓 窦性心律不齐 sinus arrest窦性停搏 ectopic rhythm异位心律 Passive ectopic rhythm被动性异位心律 Escaped 逸博 Escapedrhythm 逸博心律 Active ectopic rhythm主动性异位心律 期前收缩Premature Contraction Paroxysmal tachycardia阵发性心动过速 atrial flutter房扑， atrial fibrillation房颤 ventricular flutter室扑， ventricular fibrillation室颤 Abnormal impulse comduction 冲动传导异常 Physiological:生理性： interference and separation of AV干扰和房室分离 pathological病理性： blo