心律失?？傉撆嘤?xùn)課件

1、心律失常總論心律失?？傉揙utlineArrhythmia is any of a group of conditions in which the electrical activity of the heart is irregular or is faster or slower than normal. The heartbeat may be too fast (over 100 beats per minute) or too slow (less than 60 beats per minute), and may be regular or irregular. A heart

2、 beat that is too fast is called tachycardia and a heart beat that is too slow is called bradycardia. Although many arrhythmias are not life-threatening, some can cause cardiac arrest.心律失?？傉?2022/10/4OutlineArrhythmia is any of a DefinitionThe Origin, Rate, Rhythm, Conduct velocity and sequence of h

3、eart activation are abnormally心律失?？傉?2022/10/4DefinitionThe Origin, Rate, RhArrythmia related CardioanatomyThe cardiac muscle majority is composed of the ordinary cardiac muscle textile fiber, the small part for the cardiac muscle textile fiber of special differentiation, latter composes the cardiac

4、 pacing-conduction system心律失?？傉?2022/10/4Arrythmia related CardioanatomCardiac Conduction SystemSAN Internodal pathways AVN His bundle L./R. bundle branch Purkinje fibers2022/10/4心律失?？傉?Cardiac Conduction SystemSAN Pacing conduction system心律失?？傉?2022/10/4Pacing conduction system心律失?？傉揚(yáng)athogenesis an

5、d Inducement of Arrhythmia Some physical conditionPathological heart diseaseOther system disease Electrolyte disturbance and acid-base imbalancePhysical and chemical factors or toxicosis2022/10/4心律失?？傉?Pathogenesis and Inducement oMechanism of ArrhythmiaAbnormal heart pulse formationSinus pulseEctop

6、ic pulseTriggered activityAbnormal heart pulse conductionReentryConduct block2022/10/4心律失?？傉?Mechanism of ArrhythmiaAbnormaPhase 1快速?gòu)?fù)極初期：鉀離子外流Phase 0 快速或上升鈉離子內(nèi)流入進(jìn)入細(xì)胞進(jìn)行除極Phase 2 平臺(tái)期: 持續(xù)的鈉離子內(nèi)流和緩慢鈣離子內(nèi)流和鉀離子外流Phase 3 快速?gòu)?fù)極末期: 鉀離子外流Phase 4 靜息期5 Phases心肌細(xì)胞的動(dòng)作電位9心律失?？傉揚(yáng)hase 1Phase 0 Phase 2 PhaseAbnormal hea

7、rt pulse formationAutomaticityTriggered activity觸發(fā)機(jī)制后電位產(chǎn)生于動(dòng)作電位的第3相（早期）或第4相（晚期）可觸發(fā)心律失常2022/10/4心律失常總論10Abnormal heart pulse formationAutomaticity Heart cells other than those of the SA node depolarize faster than SA node cells, and take control as the cardiac pacemaker. Factors that enhance automatic

8、ity include: SANS, PANS, CO2, O2, H+, stretch, hypokalemia and hypocalcaemia. Examples: Ectopic atrial tachycardia or multifocal tachycardia in patients with chronic lung disease OR ventricular ectopy after MI2022/10/4心律失?？傉?1Automaticity Heart cells otherTriggered activity is like a domino effect w

9、here the arrhythmia is due to the preceding beat. Delayed after-depolarizations arise during the resting phase of the last beat and may be the cause of digitalis-induced arrhythmias. Early after-depolarizations arise during the plateau phase or the repolarization phase of the last beat and may be th

10、e cause of torsades de pointes (ex. Quinidine induced)2022/10/4心律失?？傉?2Triggered activity is like a Abnormal heart pulse conduction:Reentry: most common心律失常總論132022/10/4Abnormal heart pulse conductioFast Conduction PathSlow RecoverySlow Conduction PathFast RecoveryReentry RequiresElectrical ImpulseC

11、ardiac Conduction Tissue2 distinct pathways that come together at beginning and end to form a loop. A unidirectional block in one of those pathways. Slow conduction in the unblocked pathway. 2022/10/4心律失?？傉?4Fast Conduction PathSlow ConduFast Conduction PathSlow RecoverySlow Conduction PathFast Reco

12、veryThe “Re-Entry” Mechanism of Ectopic Beats & RhythmsElectrical ImpulseCardiac Conduction TissueTissues with these type of circuits may exist: in microscopic size in the SA node, AV node, or any type of heart tissue in a “macroscopic” structure such as an accessory pathway in WPW2022/10/4心律失?？傉?5F

13、ast Conduction PathSlow ConduFast Conduction PathSlow RecoverySlow Conduction PathFast RecoveryPremature Beat ImpulseCardiac Conduction Tissue1. An arrhythmia is triggered by a premature beat The beat cannot gain entry into the fast conducting pathway because of its long refractory period and theref

14、ore travels down the slow conducting pathway only Repolarizing Tissue (long refractory period)The “Re-Entry” Mechanism of Ectopic Beats & Rhythms2022/10/4心律失?？傉?6Fast Conduction PathSlow Condu3. The wave of excitation from the premature beat arrives at the distal end of the fast conducting pathway,

15、which has now recovered and therefore travels retrogradely (backwards) up the fast pathway Fast Conduction PathSlow RecoverySlow Conduction PathFast RecoveryCardiac Conduction TissueThe “Re-Entry” Mechanism of Ectopic Beats & Rhythms2022/10/4心律失常總論173. The wave of excitation fro4. On arriving at the

16、 top of the fast pathway it finds the slow pathway has recovered and therefore the wave of excitation re-enters the pathway and continues in a circular movement. This creates the re-entry circuitFast Conduction PathSlow RecoverySlow Conduction PathFast RecoveryCardiac Conduction TissueThe “Re-Entry”

17、 Mechanism of Ectopic Beats & Rhythms2022/10/4心律失?？傉?84. On arriving at the top of Atrial Re-entry atrial tachycardia atrial fibrillation atrial flutterAtrio-Ventricular Re-entry Wolf Parkinson White supraventricular tachycardiaVentricular Re-entry ventricular tachycardiaAtrio-Ventricular Nodal Re-e

18、ntry supraventricular tachycardiaRe-entry Circuits as Ectopic Foci and Arrhythmia Generators2022/10/4心律失?？傉?9Atrial Re-entryAtrio-VentriculbRADYCARDIASA slow rhythm (less than 60 beats/min)May be caused by a slowed signal from the SAN, a pause in the normal activity of the SAN, or by blocking of the

19、 electrical impulse on its way from the atria to the ventricles (AV block or heart block)May also be present in the normally functioning heart of endurance athletes or other well-conditioned persons2022/10/4心律失?？傉?0bRADYCARDIASA slow rhythm (lesMECHANISM OF BRADYCARDIAS竇房結(jié)自律性受損如因炎癥、缺血、壞死或纖維化可致竇房結(jié)功能衰

20、竭，起搏功能障礙，引起竇性心動(dòng)過緩，竇性停搏傳導(dǎo)阻滯SAN及A病變，可引起S-A阻滯等AVB是由于AVN或房室束的傳導(dǎo)功能降低，SAN的興奮激動(dòng)不能如期向下傳導(dǎo)而引起，可分為生理性和病理性兩種病理性常見于風(fēng)濕性心肌炎、白喉及其他感染、冠心病、洋地黃中毒等生理性多系迷走神經(jīng)興奮性過高心律失常總論212022/10/4MECHANISM OF BRADYCARDIAS竇房結(jié)自律Classification of ArrhythmiaAtrialJunctional arrhythmiaVentricularHeart blocksSudden arrhythmic death syndromeAr

21、rhythmia may be classified by rate (normal sinus rhythm, tachycardia, bradycardia) or mechanism (automaticity, reentry, junctional, fibrillation).It is also appropriate to classify by site of origin:心律失?？傉?22022/10/4Classification of ArrhythmiaAtDiagnosis of ArrhythmiaMedical HistoryPhysical Examina

22、tionLaboratory Test心律失常總論232022/10/4Diagnosis of ArrhythmiaMedical心律失?？傉?42022/10/4心律失?？傉?42022/10/22022/10/4心律失?？傉?52022/10/2心律失常總論252022/10/4心律失?？傉?62022/10/2心律失?？傉?6ELECTROCARDIOGRAM“5” steps approach to arrhythmiasStep1: Is there a “QRS”Step2: Is there a “P” Wave Step3: What is the relationship

23、between the P waves and the QRS complexes? Step4: Calculate rateStep5: Miscellaneous2022/10/4心律失?？傉?7ELECTROCARDIOGRAM“5” steps appStep 1: Is there a “QRS” (No pulse)YESNOCHAOTIC FLAT LINEWIDENARROWPEAVFAsystoleVT2022/10/4心律失?？傉?8Step 1: Is there a “QRS” (No Step 2: Is there a “P” WaveYESNOVARYCONST

24、ANTMORPHOLOGYRATE220 to 350AFJUNCTIONALInvertedRR IntervalJUNCTIONALAtrial Flutter2022/10/4心律失?？傉?9Step 2: Is there a “P” WaveYES2022/10/4心律失常總論302022/10/2心律失?？傉?02022/10/4心律失?？傉?12022/10/2心律失?？傉?1Step 3: What is the relationship between the P waves and the QRS complexes?2022/10/4心律失常總論32Step 3: Wha

25、t is the relationsh 0.2Io AVBConstant ?YesIIo AVB type 2NoRR intervalYesIIIoAVBNoType1 IIoPR intervalPR intervalHEART BLOCKn“P” = n“QRS” ?NoYesConstant?2022/10/4心律失常總論33 0.2Io AVBConstant1st Degree block(AV Nodal Delay)2022/10/4心律失?？傉?41st Degree block(AV Nodal Del2022/10/4心律失常總論352022/10/2心律失?？傉?52

26、022/10/4心律失常總論362022/10/2心律失常總論36Event Monitors Holter monitoring: Document symptomatic and asymptomatic arrhythmias over 24-48 hours. Can also evaluate treatment effectiveness in a-fib, pacemaker effectiveness and identify silent MIs. Trans-telephonic event recording: patient either wears monitor f

27、or several days or attaches it during symptomatic events and an ECG is recorded and transmitted for evaluation via telephone. Only 20% are positive, but still helpful.2022/10/4心律失?？傉?7Event Monitors Holter monitoriExercise testing Symptoms only appear or worsen with exercise. Also used to evaluate m

28、edication effectiveness (esp. flecanide & propafenone) You can assess SA node function with exercise testing.Mobitz 1 (Wenkebach) is blockage at the AV node, so catecholamines from exercise actually help! Mobitz 2 is blockage at bundle of His, so it worsens as catecholamines from exercise increase A

29、V node conduction, thus prognosis is worse.*PVCs occur in 10% without and 60% of patients with CAD. *PVCs DO NOT predict severity of CAD (neither for nor against)! 2022/10/4心律失常總論38Exercise testing Symptoms onlySignal Averaged ECGUsed only in people post MI to evaluate risk for v-fib or v-tach. Dama

30、ge around the infarct is variable, so this measures late potentials (low-signal, delayed action potentials) as they pass through damaged areas. Positive predictive value is 25%-50% but negative predictive value is 90%-95%, thus if test is negative, patient is at low risk. 2022/10/4心律失?？傉?9Signal Ave

31、raged ECGUsed only iElectrophysiologic Testing Catheters are placed in RA, AV node, Bundle of HIS, right ventricle, and coronary sinus (to monitor LA and LV). Used to evaluate cardiogenic syncope of unknown origin, symptomatic SVT, symptomatic WPW, and sustained v-tach. *Ablative therapy is benefici

32、al in AV node reentry, WPW, atrial tachycardia, a-flutter, and some v-tach. Complication is 1%2022/10/4心律失常總論40Electrophysiologic Testing CaManagementPhysical maneuvers, Medications, Electricity conversion, or Electro- or cryo-cautery.The method of cardiac rhythm management depends firstly on whethe

33、r or not the affected person is stable or unstable心律失常總論412022/10/4ManagementPhysical maneuvers, Therapy PrincipalPathogenesis therapyStop the arrhythmia immediately if the hemodynamic was unstableIndividual therapy2022/10/4心律失?？傉?2Therapy PrincipalPathogenesis 心律失?？傉撆嘤?xùn)課件Anti-arrhythmia AgentsAnti-t

34、achycardia agentsAnti-bradycardia agents2022/10/4心律失?？傉?4Anti-arrhythmia AgentsAnti-tacAnti-tachycardia agentsModified Vaugham Williams classificationI class: Natrium channel blockerII class: -receptor blockerIII class: Potassium channel blockerIV class: Calcium channel blockerOthers: Adenosine, Dig

35、ital2022/10/4心律失?？傉?5Anti-tachycardia agentsModifiePhase 1快速?gòu)?fù)極初期：鉀離子外流Phase 0 快速或上升鈉離子內(nèi)流入進(jìn)入細(xì)胞進(jìn)行除極Phase 2 平臺(tái)期: 持續(xù)的鈉離子內(nèi)流和緩慢鈣離子內(nèi)流和鉀離子外流Phase 3 快速?gòu)?fù)極末期: 鉀離子外流Phase 4 靜息期5 Phases心肌細(xì)胞的動(dòng)作電位46心律失?？傉揚(yáng)hase 1Phase 0 Phase 2 PhaseClassification of AADs類別 亞 類 電 生 理 效 應(yīng) 代 表 制 劑 新 制 劑 傳導(dǎo)速度 不應(yīng)期 Ap時(shí)限 a多奎尼丁Ajmaline、Pi

36、rmenol、Aprindinb/利多卡因Maxiletine、TocainidecEncainidePropafenone、Flecainide、Lorcainide、Ethmozide心得安=胺碘酮Sotabl異搏定硫氮唑酮Bepridi心律失?？傉?7其它藥物包括： 洋地黃類(臨床上稱之為第五類)以及新斯的明、甲氧胺、氯化鉀、硫酸鎂、ATP等抗緩慢心律失常的藥物，包括：擬交感胺類、阿托品類、堿性藥物等 2022/10/4Classification of AADs類別 亞 類 電Clinical usage: Ia classGuinidineProcainamideDisopyrami

37、de: Side effect: like M-cholinergic receptor blocker Less use in clinic 2022/10/4心律失?？傉?8Clinical usage: Ia classGuinidClinical usage: Ib classLidocaine MexiletinePerfect to ventricular tachyarrhythmia2022/10/4心律失常總論49Clinical usage: Ib classLidocaClinical usage: Ic classMoricizine PropafenoneCan be

38、 used in ventricular and/or supra-ventricular tachycardia and extrasystole.2022/10/4心律失常總論50Clinical usage: Ic classMoriciClinical usage: II classPropranolol: Non-selectiveMetoprolol: Selective 1-receptor blocker, Perfect to hypertension and coronary artery disease patients associated with tachyarrhythmia. -receptor blocker2022/10/4心律