资源描述
,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,电生理相关资料,Cardiac vein stenosis,PTCA with 3.5 mm balloon,Final result,Modified,Seldinger,technique for percutaneous catheter sheath introduction,Sequence of P Wave Generation,Sinus,Node,SA,Junction,Atrium,(P wave),Non-visible process on the EKG,AV node,“Slow,zone”,IVC,Lead II,SUMMARY,Mechanisms of SVT,Atrial,Tachycardia,AVNRT,AVRT,FP,SP,Differential Diagnosis of NCT,Short RP,AVRT,AT,Slow-Slow AVNRT,Long RP,AT,Atypical AVNRT,PJRT,P buried in QRS,Typical AVNRT,AT,JET,SUMMARY,Obtain a 12 lead ECG. The location of the P wave will dictate the differential diagnosis,If,hemodynamically,unstable (chest pain, heart failure, hypotension)- CARDIOVERSION,If,hemodynamically,stable -AV NODAL AGENT,Long term therapy depends on mechanism and can be conservative, pharmacologic or invasive,EP study often needed for definitive characterization of mechanism and can cure most,SVTs,with 90% success rate,AVNRT,Atrial flutter sawtooth or picket fence,Atrial flutter with rapid response,Arrhythmias: SA Block,P,QRS T,Arrhythmias: Atrial Flutter,Steps to reading ECGs,What is the rate? Both atrial and ventricular if they are not the same.,Is the rhythm regular or irregular?,Do the P waves all look the same? Is there a P wave for every QRS and conversely a QRS for every P wave?,Are all the complexes within normal time limits?,Name the rhythm and any abnormalities.,Rate,Look at complexes in a 6-second strip and count the complexes; that will give you a rough estimate of rate,Count the number of large boxes between two complexes and divide into 300,Count the number of small boxes between two complexes and divide into 1500,Estimate rate by sequence of numbers (see next slide),Bundle branch blocks,Look at the QRS morphology in V,1,and V,6,AVNRT,Acute treatment,ATP or Verapamil,Cardioversion if BP,Long term,Drugs, verapamil or b-blocker,EPS and RFA,AVRT,WPW or concealed accessory pathway,acute and chronic treatment similar to AVNRT,avoid b-blocker and verapamil in known WPW,Atrial Flutter,Marcoreentrant circuit in RA,terminate by cardioversion with high success rate,poorly controlled by medical therapy,EPS + RFA,“Typical isthmus dependent atrial flutter” is due to a macro reentrant circuit around the tricuspid valve,This rhythm can be stopped by pacing and cured with ablation,Embolic risk may be less than in fibrillation, but same recommendations apply,Electrophysiology II Supraventricular Arrhythmias,Atrial Flutter,Ventricular rate 150 bpm,“Saw tooth” p waves,Atrial Flutter,Electrophysiology II Supraventricular Arrhythmias,Atrioventricular Nodal Reentrant Tachycardia,(AV Node Reentry or AVNRT),Most common cause of paroxysmal SVT in the young adult,Occurs over a small reentrant circuit located near the AV node,The circuit consists of a fast and slow pathway connected by a common top and bottom pathway,Electrophysiology II Supraventricular Arrhythmias,AV Node Reentry Tachycardia,Rate of 145,bpm,(Short RP tachycardia),Electrophysiology II Supraventricular Arrhythmias,Retrograde p waves,RP = 60,msec,Ectopic Atrial Tachycardia,(Long RP tachycardia),Uncommon cause of paroxysmal SVT in the young adult (0.09s,预激波额面电轴右偏（,90,120,度）,右侧房室旁路的定位标准,V1,导联,QRS,波主波方向向下（多呈,rS,型）,V1,导联,P,波和,QRS,波融合，二者间无等电位线，,PR0.07s,预激波额面电轴左偏（,30,60,度）,右后、右侧游离壁：,、,aVL,、,V5,、,V6,导联预激波正向，,、,、,aVF,导联预激波负向或正负双向。,右前游离壁：,、,、,aVF,导联预激波正向或正负双向。,前间隔房室旁路的定位标准,V1,导联,QRS,波主波方向向下（多呈,rS,型）,V1,导联,P,波和,QRS,波融合，二者间无等电位线，,PR0.21 would be classified as first degree block. Usually this block is above His bundle,Second degree,- some P waves are not followed by QRS. Often has a regular sequence, i.e., 2:1 or 3:2.,The first number is the number of P waves present and the second is the number of QRSs. What is this?,Mobitz I (Wenckebach),the PR progressively lengthens with one P wave for every QRS until a beat is dropped. Usually the block is above His bundle.,This is common in coronary patients and is caused by increased vagal tone and usually eventually disappears with no problems,Mobitz II,the PR is constant but with occasional dropped beats. This is a more serious arrhythmia because the injury is probably in fast conducting tissue below the His bundle which is not under vagal control.,This is unambiguously Mobitz II,It is a dangerous arrhythmia because the heart may suddenly start beating very slowly or even stop.,Complete heart block,. Since there is no conduction down the AV node pathway atria and ventricles beat regularly but at different rates.,Slow ventricular rate,Usually treated with pacemaker,May be temporary or intermittent.,Can be induced by drugs that cause increased,vagotonia,WPW: Normally conducting cardiac muscle bridges the gap between atria and ventricles.,The accessory pathway activates the ventricle,before,normal activation via the AV node.,The PR interval is 100b/min,1. Normal P waves,2. Normal or shortened PR interval,3. QRS and T vectors are normal,4. ST segments are normal,5. RR interval short,15mm,1500/100 = 15,Fig 3,Normal sinus rhythm,Sinus tachycardia,Sinus bradycardia,Sinus Bradycardia,25mm,1500/60 = 25,Premature ventricular contraction (PVC),1. Arises from ectopic focus in ventricles,2. Early QRS not preceded by a P wave (see fig 4),3. Will have an unusual QRS shape,a) odd vector,b) prolonged QRS duration,Premature ventricular contraction (PVC),1. Arises from ectopic focus in ventricles,2. Early QRS not preceded by a P wave (see fig 4),3. Will have an unusual QRS shape,a) odd vector,b) prolonged QRS duration,4. A compensatory pause,Multifocal,PVCs,.,Two separate foci are originating PVCs,Irritable ventricle,IF all PVC are identical it is from one ectopic site (,Unifocal,).,Premature atrial contraction (PAC),1. Arises from an ectopic focus in the atria.,2. Will have an identifiable P wave but the shape of the P wave may be altered,3. May have a normal QRS,4. May have a compensatory pause,The QRS may be altered if some of the ventricle is still in its refractory period.,The compensatory pause is lacking because the SA node was reset.,The rhythm has been shifted.,Atrial fibrillation,1. Irregularly irregular,2. No P waves,The AV node keeps the ventricular rate low,May be treated with drugs to depress AV conduction and slow the ventricular rhythm: Beta blockers, calcium channel blockers,Common: will occur in about 1/3 of the population,Not a serious arrhythmia unless in WPW,Electrical reentry can cause fibrillations and,tachycardias,.,Ventricular tachycardia,(Fig 9),1. Regularly occurring rhythm originating from a regular ventricular ectopic focus.,2. QRS morphology is usually like a PVC,Because the cardiac output is very low it usually produces myocardial ischemia and often progresses to ventricular fibrillation,Ventricular fibrillation (VF),1. Thought to be a reentrant excitation of the ventricles; premature impulse may arise during vulnerable period,2. Irregular baseline with no identifiable waves,3. No cardiac output. Usually the cause of sudden death,4. May be the result of ischemia, lightning strike, electrocution, chest trauma, or drugs,5. Requires CPR and electrical,difibrillation,. Patients do not spontaneously recover.,Extended phase two cause long QT syndrome.,Q-T interval is rate- dependent and is an index of the duration of phase 2 in the ventricular AP,12 x 40 = 480 ms,12 blocks,Long QT syndrome,Prolonged duration of phase 2 causes an early,afterdepolarization,. That can trigger an early action potential causing a reentrant tachycardia,Patients may experience attacks of VT with,torsades de pointes,- a waxing and waning of the QRS morphology (as if circling around a point).,3. Long QT is induced by some drugs and can be due to genetic abnormalities in some potassium and calcium channels. At present 5 separate genetic defects have been identified which cause long QT,14 STEPS TO ASSURE A SUCCESSFUL READING AND UNDERSTANDING OF AN UNKNOWN ECG,1. Is the ventricular rhythm regular?2. Are there P waves?3. Is the atrial rhythm regular?4. Is there one P wave for each QRS?5. What are the atrial and ventricular rates?6. What is the P-R interval?7. Is the P-R interval constant?8. Are there extra or premature beats?9. What is the QRS duration?10. Does the QRS morphology indicate presence of a conduction defect?11. What is the mean electrical QRS axis?12. What is the mean electrical P wave axis?13. Is there S-T segment deviation?14. Are there pathologic Q waves?,Fig 12 a,summary of heart blocks.,a summary of other arrhythmias,RA,LA,LV,RV,Types of Supraventricular Tachyarrhythmias,Sinus Node Reentry,Atrial Flutter,Automatic Atrial Tachycardia,Reentrant Atrial Tachycardia,Atrioventricular Nodal,Reentry (AVNRT),AV Reentry via an Accessory,AV Connection (AVRT),Atrial Fibrillation (Not Shown),Types of Paroxysmal Supraventricular Tachycardia,AV NodalReentry,AV ReciprocatingTachycardia,Sinus Nodal Reentry,Intra-,atrial,Reentry,Automatic,Atrial,Tachycardia,Mechanisms of Paroxysmal Supraventricular Tachycardias,Enhanced Automaticity:,Paroxysmal and Acute,Chronic,Re-entry without Bypass Tracts:,AV Nodal Re-entry: Slow Fast/Fast Slow,Sinoatrial Nodal Re-entry,Intra-atrial Re-entry,Re-entry in Association with Bypass Tracts:,Re-entry with Anterograde AV Conduction (Orthodromic),With Evidence of Pre-excitation of 12-Lead ECG,Concealed WPW (Bypass Tract Conducting only Retrogradely ),Re-entry with Anterograde Conduction Over Bypass tract (Antidromic) During Tachycardia,Accessory Pathways: Concealed Bypass Tract AV Reentrant Tachycardia,AV Node,Bundle of His,Left Bundle Branch,P,Right Bundle Branch,Concealed Bypass,Tract,Electrical Conduction in,Atrial Flutter,AV Node,Ventricular Rate 150-160 (Most Often 2:1 AV Block),ECG of Flutter,Baseline Coarsely or Finely Irregular; P Waves Absent.,Ventricular Response (QRS) Irregular, Slow or Rapid,Coarse Fibrillation,Fine Fibrillation,Atrial Fibrillation,Scheidt,S,Erlebacher,JA, Netter FH.,Basic,Electrocardiography ECG,. Ciba-Geigy: First Printing, 1986, p23.,Electrocardiogram,AF is Associated With,CV Diseases,CT surgery,Valvular or,congential disease,Hypertension,Cardiomyopathy,Heart failure,Myocardial ischemia/MI,Peri/myocarditis,Infiltrative heart disease,Cardiac trauma,Systemic Diseases,Age,DTs, sympathetic storm,Electrolyte disorders,Thyrotoxicosis,Fever/hypothermia,Hypovolemia,Diabetes,Anemia,Pulmonary disease,Cerebrovascular disease,Antiarrhythmic Drugs,vs. Therapeutic Goal,Atrium,His Purkinje,Ventricle,AP,AV Node,Ibutilide,Quinidine,Procainamide,Disopyramide,Flecainide,Propafenone,Sotalol,Amiodarone,Vagal Stimulation,Digoxin,b,-Blocking Drugs,Verapamil,Diltiazem,Adenosine,Atrial fibrillation,Atrial flutter,
展开阅读全文