內(nèi)科護(hù)理學(xué)課件 英語(yǔ) 考試資料dysrhythmias-文檔資料

1、properties of cardiac tissue 心臟組織的特性 automaticity 自律性自律性: ability to initiate an impulse spontaneously and continuously. excitability興奮性興奮性: ability to be electrically stimulated. contractility收縮性收縮性: ability to respond mechanically to an impulse. conductivity傳導(dǎo)性傳導(dǎo)性: ability to transmit an impulse a

2、long a membrane in an orderly manner.conduction system: a brief review傳導(dǎo)系統(tǒng)傳導(dǎo)系統(tǒng) p wave begins with the firing of the sa node and represents depolarization去極化去極化 of the fibers of the atria心房心房, resulting in atrial contraction心房收縮心房收縮. the qrs complex represents depolarization去極化去極化 of the ventricles心心

3、室室, resulting in ventricular contraction心室收縮心室收縮. the t wave represents repolarization復(fù)極復(fù)極of the ventricles心室心室, or the time at which the ventricles return to the prestimulated state.conduction system: a brief review intervals波間隔波間隔between these waves reflects the lengths of time it takes for the im

4、pulses 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房室結(jié)房室結(jié), bundle of his希氏束希氏束, and purkinje浦肯野纖維浦肯野纖維. the qrs interval represents the time it takes for depolarization去去極化極化of both ventricles. th

5、e qt interval represents the time it takes for complete depolarization除極除極and repolarization復(fù)極復(fù)極of the ventricles.dysrhythmia dysrhythmia is an abnormal cardiac rhythm in terms of the frequency of the impulse頻率, rhythm節(jié)律, origin site起源部位, conduction velocity傳導(dǎo)速度and excitement order激動(dòng)次序.classificatio

6、n of dysrhythmia 心律失常的分類心律失常的分類 abnormal impulse formation 沖動(dòng)形成異常沖動(dòng)形成異常sinus dysrhythmia 竇性心律失常sinus tachycardia竇性心動(dòng)過速竇性心動(dòng)過速sinus bradycardia竇性心動(dòng)過緩竇性心動(dòng)過緩竇性心律不齊sinus arrest竇性停搏ectopic rhythm異位心律passive ectopic rhythm被動(dòng)性異位心律escaped 逸博escapedrhythm 逸博心律active ectopic rhythm主動(dòng)性異位心律期前收縮期前收縮premature cont

7、ractionparoxysmal tachycardia陣發(fā)性陣發(fā)性心動(dòng)過速心動(dòng)過速atrial flutter房撲，房撲， atrial fibrillation房顫房顫ventricular flutter室撲，室撲， ventricular fibrillation室顫室顫 abnormal impulse comduction 沖動(dòng)傳導(dǎo)異常沖動(dòng)傳導(dǎo)異常 physiological:生理性： interference and separation of av干擾和房室分離 pathological病理性： block of sa竇房傳導(dǎo)阻滯 block of atrial pathwa

8、y房?jī)?nèi)傳導(dǎo)阻滯 block of atrioventricular pathway房室傳導(dǎo)阻滯房室傳導(dǎo)阻滯 block of bundle branch束支或分支阻滯或室內(nèi)阻滯 房室間傳導(dǎo)途徑異常：wpw 預(yù)激綜合征sinus tachycardia竇性心動(dòng)過速 clinical association: it associated with physiological stressors such as exercise, fever, pain, anxiety, hypotension, hypovolemia低血容量 , anemia, hypoxemia低氧血癥 , hypoglyc

9、emia低血糖癥 , myocardial ischemia, chf, and thyrotoxicosis甲狀腺毒癥. it also can be affected by drugs such as epinephrine, norepinephrine, caffeine, atropine阿托品 , theophylline茶鹼 , nifedipine硝苯地平 , hydralazine胼酞嗪(降壓藥)sinus tachycardia竇性心動(dòng)過速 significance: the clinical significance of sinus tachycardia depend

10、s on patients tolerance of the increased hr. the patient may have symptoms of dizziness頭頭暈暈, hypotension低血壓低血壓may occur. angina or an increase in infarct size may accompany persistent sinus tachycardia in the patient with mi心肌梗塞心肌梗塞. treatment the treatment is determined by underlying causes. in cer

11、tain setting, -blocker therapy is used to reduced hr and decrease myocardial oxygen consumption.sinus tachycardiaecg 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

12、and the qrs complex has a normal contour.sinus bradycardia 竇性心動(dòng)過緩竇性心動(dòng)過緩 clinical association 臨床聯(lián)系臨床聯(lián)系: it occurs in response to hypothermia低體溫 , carotid sinus massage按壓頸動(dòng)脈竇按壓頸動(dòng)脈竇, increased intraocular pressure眼內(nèi)壓眼內(nèi)壓 , increased vagal tone迷走神經(jīng)緊張迷走神經(jīng)緊張 , and administration of parasympathomimetic擬副交感神

13、經(jīng)藥drugs. diseases states associated with sinus bradycardia are hypothyroidism 甲狀腺機(jī)能減退 , increased intracranial pressure顱內(nèi)壓 , obstructive jaundice阻塞性黃疸 and inferior wall mi.sinus bradycardia 竇性心動(dòng)過緩竇性心動(dòng)過緩 significance意義意義: the clinical significance of sinus bradycardia depends on how the patients tole

14、rates it hemodynamically. hypotension with decreased co may occur in some circumstances.treatment治療治療: for the patient with symptoms, administration of atropine阿托品阿托品 , and anticholinergic drug抗膽堿能藥抗膽堿能藥 . pacemaker therapy may be required. sinus bradycardia竇性心動(dòng)過緩竇性心動(dòng)過緩ecg characteristics hr is less

15、 than 60 bpm, rhythm is regular. the p wave precedes each qrs complex. the pr interval is normal and the qrs complex has a normal contour and normal length.premature atrial contraction (pac)房性期前收縮房性期前收縮 a pac is a contraction originating from an ectopic focus異位病灶異位病灶 in the atrium in a location othe

16、r than the sinus node. it originates in the left or right atrium and travels across the atria by an abnormal pathway, creating a distorted p wave. at the av node房室結(jié)房室結(jié), it is stopped (nonconducted pac), delayed (lengthened pr interval), or conducted normally. it moves through the av node, and in mos

17、t cases, it is conducted normally through the ventricles.premature atrial contraction (pac)房性期前收縮房性期前收縮 clinical association in a normal heart, it can result from stress or the use of caffeine, tobacco or alcohol. it also can result from diseases states such as infection, inflammation, hyperthyroidi

18、sm甲亢甲亢, copd, heart diseases, valvular diseases. a pac and also be caused by enlarged atria. significance: a pac may be prelude前奏前奏to supraventricular tachycardias室上性心動(dòng)過速室上性心動(dòng)過速. treatment: depends on patients symptoms. withdrawal of sources of stimulation such as caffeine may be warranted. drugs su

19、ch as digoxin, quinidine奎尼丁, , procainamide普魯卡因, flecainide氟卡尼 , and -blockers can be used.premature atrial contraction (pac)房性期前收縮房性期前收縮ecg characteristics hr varies and rhythm is irregular. the p wave may be notched缺跡缺跡 or have negative deflection逆向逆向的偏轉(zhuǎn)的偏轉(zhuǎn), or it may be hidden in the preceding t

20、wave. qrs is usually normal, if the qrs interval is 0.10 second or longer, abnormal conduction through the ventricle is present. the pr interval may be shorter or longer than normal pr interval, but its within normal limit.paroxysmalsupraventriculartachycardia(psvt)陣發(fā)性室上性心動(dòng)過速陣發(fā)性室上性心動(dòng)過速pavt is dysrhy

21、thmia originating in an ectopic focus anywhere above the bifurcation of the bundle of his希氏束希氏束分支分支.psvt occurring via an accessory pathway旁路途徑旁路途徑is designated as orthodromic順向順向or antidromic逆逆向性向性 tachycardia.paroxysmalsupraventriculartachycardia(psvt)陣發(fā)性室上性心動(dòng)過速陣發(fā)性室上性心動(dòng)過速 orthodromic順向順向refers to

22、anterograde順時(shí)順時(shí), or forward 向前向前conduction through the av node and retrograde逆行逆行, backward 向后向后conduction, through the accessory pathway. antidromic逆逆向向refers to the opposite: anterograde conduction順時(shí)傳導(dǎo)順時(shí)傳導(dǎo)through the accessory path 旁路途徑旁路途徑 and retrograde conduction 逆行傳導(dǎo)逆行傳導(dǎo)through the av node.par

23、oxysmal supraventricular tachycardia (psvt)陣發(fā)性室上性心動(dòng)過速陣發(fā)性室上性心動(dòng)過速 clinical association in the normal heart, psvt is associated with overexertion, emotional stress, changes of position, deep inspiration, and stimulation and stimulants such as caffeine and tobacco. in a diseases state, psvt is associate

24、d with rheumatic heart disease, wolff-parkinson-white (wpw)預(yù)激綜合癥預(yù)激綜合癥(conduction via accessory pathways), digitailis intoxication, coronary artery disease or cor pulmonary.paroxysmal supraventricular tachycardia (psvt)陣發(fā)性室上性心動(dòng)過速陣發(fā)性室上性心動(dòng)過速 significance: a prolonged episode and hr greater than 180 bpm

25、 may precipitate a decreased co with hypotension and myocardial ischemia. treatment: vagalstimulation迷走神經(jīng)刺激迷走神經(jīng)刺激: carotid massage按按摩頸動(dòng)脈竇摩頸動(dòng)脈竇or the valsalva meneuver valsalva動(dòng)作動(dòng)作 pharmacologic therapy: adenosine腺苷腺苷 , verapamil異搏定異搏定 , diltiazem地爾硫卓地爾硫卓 , digitalis洋地黃洋地黃 and propranolol心得安心得安 . how

26、ever, dititalis洋地黃洋地黃and calcium channel blockers can cause hemodynamic collapse in wpw syndrome.paroxysmal supraventricular tachycardia (psvt)陣發(fā)性室上性心動(dòng)過速陣發(fā)性室上性心動(dòng)過速ecg characteristics hr is 150to250 bpm and rhythmisregular. the p wave is often hidden in the preceding t wave and has an abnormal contou

27、r. the pr interval may be prolonged, shortened or normal qrs complex may have a normal or abnormal contour.atrial flutter 心房撲動(dòng) atrial flutter is identified by recurring, regular, sawtooth-shape flutter waves鋸齒形撲波鋸齒形撲波. atrial flutter is relatively rare dysrhythmia.clinical association: it rarely occ

28、urs in a normal heart. in disease states, it is associated with cad, hypertension, mitral valve disorders, pulmonary embolus肺栓塞肺栓塞, cor pulmoale肺心肺心病病, cardiomyopathy心肌病心肌病, hyperthyroidism甲甲亢亢 and the use of drugs such as digitalis, quinidine奎尼丁 , and epinephrine.atrial flutter心房撲動(dòng) significance: hi

29、gh ventricular rates associated with atrial flutter can decrease co and cause serious consequence such as heart failure, especially in the patient with underlying heart disease. treatment: electrical cardioversion心臟電復(fù)律心臟電復(fù)律may be used to convert the atrial flutter to sinus rhythm in an emergency sit

30、uation. drugs used include verapamil 異搏定異搏定, digoxin洋地洋地黃黃 quinidine奎尼丁奎尼丁 , procainamide普魯卡因普魯卡因 and -blockers.atrial flutter心房撲動(dòng)ecg characteristics atrial rate is 250 to 330 bpm. the ventricular rate varies according ot the conduction ratio. in 2:1 conduction, the ventricular rate is typically fou

31、nd to be apporximately 150 bpm. atrial rhythm is regular, and ventricular rhythm is usually regular. the p wave is represented by sawtooth waves鋸齒波鋸齒波or f waves. the pr interval is available. qrs complex is normal in contour.atrial fibrillation心房顫動(dòng) atrial fibrillation is characterized by a total dis

32、organization of atrial electrical activity電生理電生理活動(dòng)活動(dòng)without effective atrial contraction心房收縮心房收縮. ventricular response心室反應(yīng)心室反應(yīng)is irregular, and if the patient is untreated, the ventricular rate will be 100 to 160 bpm. the dysrhythmia may be chronic or intermitten.clinical association: it usually occ

33、urs in the patient with underlying heart disease; it also associated with thyrotoxicosis甲狀腺毒癥甲狀腺毒癥, alcoholism, infection, gastroenteritis and stress.atrial fibrillation心房顫動(dòng) significance: it often result in a decrease in co due to ineffective atrial contractions and a rapid ventricular response. thr

34、ombi血栓血栓may form in the atria as a result of ineffective atrial system may occur as a complication with subsequent development of a stroke. treatment in emergeny situation, cardioversion心臟電復(fù)心臟電復(fù)律may be used to convert atrial fibrillation to normal sinus rhythm. medication used include digoxin洋地黃洋地黃,

35、 verapamil 異異搏定搏定, quinidine奎尼丁奎尼丁 , procainamide普魯卡普魯卡diltiazem地爾硫卓地爾硫卓 , and -blockers, flecainide氟卡尼 , propafenone 普羅帕酮普羅帕酮 and sotalol施太可鹽酸索施太可鹽酸索他洛爾他洛爾 .atrial fibrillation心房顫動(dòng)ecg characteristics atrial rate may be as high as 350 to 600 bpm. the ventricular rate varies from as low as 50 to as h

36、igh as 180 bpm. atrial rhythm is chaotic混亂, and ventricular rhythm is irregular. the p wave shows fibrillatory waves房顫波房顫波(f wave), but no definite p waves can be observed. the pr interval is not measurable. qrs complex usually has a normal contour.premature ventricular contractions室性期前收縮 premature

37、ventricular contractions: is a contraction originating in a ectopic focus異位節(jié)律異位節(jié)律in the ventricles. the qrs wave is usually wider than 0.12 seconds. the t wave is generally large and opposite in direction to the major deflection of the qrs complexpremature ventricular contractions (pvc)室性期前收縮室性期前收縮p

38、vc are initiated from different foci病灶appear different in contour不同輪廓from each other and are call multifocal pvcs多灶性期前收縮.when every other beat is pvc, it is called ventricular bigeminy心室二聯(lián)律.when every third beat is pvc, it is called ventricular trigeminy心室三聯(lián)律.premature ventricular contractions (pvc)

39、室性期前收縮室性期前收縮two consecutive pvcs are called couplets成對(duì)室性期前收縮成對(duì)室性期前收縮.three consecutive pvcs are called triplets. ventricular tachycardia室性心動(dòng)過速室性心動(dòng)過速occurs when there are three or more consecutive pvcs.when a pvc falls on the t wave of preceding beat, the r on t phenomenon r波落在波落在t波上現(xiàn)象波上現(xiàn)象 occurs and

40、 is considered to be dangerous because it may precipitate ventricular tachycardia室室性心動(dòng)過速性心動(dòng)過速or ventricular fibrillation心室顫動(dòng)心室顫動(dòng).premature ventricular contractions (pvc)室性期前收縮室性期前收縮 clinical association: is associated with stimulation such as caffeine, alcohol, aminophyline氨茶堿, epinephrine and digox

41、in. they are also associated with hypokelemia低鉀血癥低鉀血癥, hypoxia缺氧缺氧, fever, exercise, and emotional stress. disease states associated with pvc includes mi, chf and cad. significance: in heart diseases, depending on frequency, pvcs may reduce the co and precipitate angina and heart failure. . treatmen

42、t: fortreatingpvcs, lidocaine利多卡因利多卡因is the drug of choice. procainamide普魯卡因普魯卡因 is the second drug of choice if lidocaine is ineffective.premature ventricular contractions (pvc)室性期前收縮室性期前收縮ecg characteristics hr varies. rhythm is irregular because of premature beat. a retrograde逆行逆行p wave is possib

43、le, and p wave is rarely visible because is usually lost in the qrs complex of pvc. the pr interval is not measurable. qrs complex is wide and distorted in shape, more than 0.01 second.ventricular tachycardia 室性心動(dòng)過速the ecg diagnosis of ventricular tachycardia is made when a run of three or more pvcs

44、 occurs.the qrs is distorted歪曲歪曲in appearance with a duration exceeding 0.12 second and with the st-t direction pointing to the major qrs deflection.ventricular tachycardia may be sustained持續(xù)性(lasting longer than 30 seconds) or nonsustained 非持續(xù)性(lasting 30 seconds or less).ventricular tachycardia cl

45、inical association: is associated with acute mi, cad, significant electrolyte imbalances, cardiomyopathy心肌病, long qt syndrome and coronary reperfusion after thrombolytic therapy溶栓治療后冠狀動(dòng)脈再灌注. is also can be observed in the patient who has not heart diseases. significance: the appearance of ventricula

46、rtachycardia is an ominous不祥sign. it may cause a severe decreased in co . the result may be pulmonary edema肺水腫肺水腫, shock休克休克, and insufficient blood flow to the brain大腦大腦血流量不足血流量不足. ventricular fibrillation心室顫動(dòng)心室顫動(dòng)may develop.ventricular tachycardia treatment: if the patient is hemodynamically stabl

47、e, treatment consists of administration of lidocaine利多卡因利多卡因bolus, procainamide普魯卡因 is the second drug of choice if lidocaine is ineffective. if the patient is unconscious or hemodynamically unstable, immediate cardioversion心臟電復(fù)律is the recommended treatment. ventricular tachycardiaecg characteristic

48、s ventricular rate is 110 to 250 bmp. rhythm may be regular or irregular. the p wave may be dissociated from脫離qrs complex, or it may be buried in qrs complexes or t waves. the pr interval is not measurable. qrs complex is prolonged for more than 0.10 seconds and the qrs complex is distorted.ventricu

49、lar fibrillation心室顫動(dòng)ventricular fibrillation is a severe derangement of the heart rhythm characterized on the ecg by irregular undulations 波動(dòng)波動(dòng)of varying contour and amplitude.this represents the firing of multiple ectopic foci異位病灶異位病灶in the ventricle.mechanically the ventricle is simply “ quivering

50、顫抖顫抖”, and no effective contraction or co occurs.ventricular fibrillation心室顫動(dòng) clinical association: it occurs in acute mi and myocardial ischemia and in chronic diseases such as cad and cardiomyopathy心肌病心肌病. it may occur during cardiac pacing心臟起搏心臟起搏or cardiac catheterization procedures心導(dǎo)管檢查心導(dǎo)管檢查as

51、a result of catheter stimulation of the ventricle. it may also occur with coronary reperfusion冠狀動(dòng)冠狀動(dòng)脈重新灌注脈重新灌注after thrombolytic therapy溶栓治療溶栓治療. other clinical associations are accidental electrical shock, hyperkalemia高鉀血癥高鉀血癥and hypoxemia低氧血癥低氧血癥. ventricular fibrillation心室顫動(dòng)significance: it resul

52、ts in unconsciousness昏迷昏迷, absence of pulse, apnea呼吸困難呼吸困難, and seizure癲癇癲癇. if left untreated, the patient with this condition will die.treatment: immediate initiation of cardiopulmonary resuscitation心肺復(fù)蘇心肺復(fù)蘇(cpr) and initiation of advanced cardiac life support (acls) measures高級(jí)心臟生命支持高級(jí)心臟生命支持with u

53、se of defibrillation and definitive drug therapy.ventricular fibrillation心室顫動(dòng)ecg characteristicshr is not measurable.rhythm irregular and chaotic.the p is not visible.the pr interval and the qrs interval are not measurable.first degree av block i度房室傳導(dǎo)阻滯first degree av block is a type of av block in

54、which every impulse in conducted to the ventricles but the duration of av conduction is prolonged.this is manifested by pr interval greater than 0.20 second. after the impulse moves through the av node, it is usually conducted normally through the ventricle.first degree av block i度房室傳導(dǎo)阻滯clinical ass

55、ociation: it is associated with mi, chronic ischemia heart diseases, rheumatic fever風(fēng)濕熱風(fēng)濕熱, hyperthyroidism甲亢甲亢, vagal simulation and drugs such as digitalis, -blocker, flecainide 氟卡尼, and iv verapamil 異搏定異搏定.significance: first degree av block may be a precursor of high degrees of av block.treatmen

56、t: there is no treatment for the first degree av block.first degree av block i度房室傳導(dǎo)阻滯ecg characteristics atrial rate is normal, and rhythm is regular. the p wave is normal. the pr interval is prolonged for more than 0.20second. qrs complex usually has a normal contour.second degree av block, type i

57、i型 二度房室傳導(dǎo)阻滯 type i av block includes a gradual lengthening of the pr interval, and a qrs complex is droped. type i av block most commonly occurs in the av node, but it can also occur in the his-purkinje system.clinical association: type i av block may result from use of drugs such as digoxin or -blo

58、cker. it may also be associated with ischemia cardiac disease and other diseases that can slow av conduction.second degree av block, type i i型 二度房室傳導(dǎo)阻滯significance: is usually a result of myocardial ischemia in an inferior mi. it is almost transient and is usually well tolerated, however, it may be

59、a warning signal預(yù)警信號(hào)預(yù)警信號(hào)of impending significant av conduction disturbance.treatment: if the patient is symptomatic, atropine阿托品阿托品is used to increased hr or a temporary pacemaker臨時(shí)起搏器臨時(shí)起搏器may be needed, especially if the patient has an acute mi.second degree av block, type i i型 i i度房室傳導(dǎo)阻滯ecg charac

60、teristics atrial rate is normal, and ventricular rate may be slower as a result of dropped qrs complexs. ventricular rhythm is irregular. the p wave has a normal contour. the pr interval is progressively lengthens before the nonconducted p wave occurs pr間期逐步延長(zhǎng)，間期逐步延長(zhǎng)，直至下一個(gè)直至下一個(gè)p波受阻不能下傳波受阻不能下傳至心室，至心室