文档介绍：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 spontaneo分离
pathological病理性：
block of SA窦房传导阻滞
block of atrial pathway房内传导阻滞
block of atrioventricular pathway房室传导阻滞
Block of bundle branch束支或分支阻滞或室内阻滞
房室间传导途径异常：WPW 预激综合征
Sinus tachycardia窦性心动过速
Clinical association:
It associated with physiological stressors such as exercise, fever, pain, anxiety, hypotension, hypovolemia低血容量 , anemia, hypoxemia低氧血症 , hypoglycemia低血糖症 , myocardial ischemia, CHF, and thyrotoxicosis甲状腺毒症.
It also can be affected by drugs such as epinephrine, norepinephrine, caffeine, atropine阿托品 , theophylline茶硷 , nifedipine硝苯地平 , hydralazine胼酞嗪(降压药)
Sinus tachycardia窦性心动过速
Significance: The clinical significance of sinus tachycardia depends on patient’s tolerance of the increased HR.
The patient may have symptoms of dizziness头晕, hypotension低血压may occur.
Angina or an increase in infarct size may accompany persistent sinus tachycardia in the patient with MI心肌梗塞.
Treatment
The treatment is determined by underlying causes.
In certain setting, β-blocker therapy is used to reduced HR and decrease myocardial oxygen consumption.
Sinus tachycardia
ECG characteristics
HR is greater than 100 bpm, rhythm is regular.
The P wave is normal, precedes each QRS complex, and has a normal contour and fixed interval.
The PR interval is normal and the QRS complex has a normal contour.
Sinus bradycardia 窦性心动过缓
Clinical association 临床联系:
It occurs in response to hypothermia低体温 , carotid sinus massage按压颈动脉窦, increased intraocular pressure眼内压 , increased vagal tone迷走神经紧张 , and administration of parasympathomimetic拟副交感神经药drugs.
Diseases states associated with sinus bradycardia are hypothyroidism 甲状腺机能减退 , increased intracranial pressure颅内压 , obstructive jaundice阻塞性黄疸 and inferior wall MI.
Sinus bradycardia 窦性心动过缓
Significance意义:
The clinical significance of sinus bradycardia depends on how the patients tolerates it hemodynamicall