心律失常发生机制及导管消融适应症英文课件

Automatic tachycardia(AT,VT,AF)is identified by the presence of the following characteristics:Can be initiated by an isoproterenol infusion PES cannot initiate or terminate the tachycradia Can be gradually supressed with overdrive pacing,but then resumes with a gradual increase in the rate Can be terminated by propranolol These episodes have a“warm up”and/or“cool down phenomenon Cannot be terminated by adenosine,but transiently slows or suppresses,especially when it can be induced with isoproterenol(Zipes DP,Jalife J.Cardiac Electrophysiology:From cell to bedside,4th edition.2004;pg.500-501)Triggered activity(AT,VT,AF)is identified by the presence of the following characteristics:Triggered arrhythmias can be initiated with rapid pacing or exstrastimuli dependant on reaching a certain range of pacing cycle lengths No entrainment is observed,but overdrive suppression or termination occurs Delayed afterdepolarizations can be recorded near the origin using a monophasic action potential catheter before the onset,but not at sites remote from the tachycardia Is terminated by adenosine Rarely requires isoproterenol to induce it Is terminated by dipyridamole,propranolol,verapamil,edrophonium,Valsava maneuvers and carotid sinus pressure(Zipes DP,Jalife J.Cardiac Electrophysiology:From cell to bedside,4th edition.2004;pg.500-501)Microreentry(AT,AVNRT,VT)/Macroreentry(AT,AVRT,Atrial Flutter)is identified by the presence of the following characteristics:Can be reproducibly initiated and terminated by pacing and extrastimuli No delayed afterdepolarizations can be recorded using a monophasic action potential catheter Manifest and concealed entrainment observed while pacing during the tachycardia Frequently terminated by verapamil and adenosine,but adenosine usually has no effect The interval between the initiating premature beat and first beat of the AT are inversely related(Zipes DP,Jalife J.Cardiac Electrophysiology:From cell to bedside,4th edition.2004;pg.500-501)TYPICAL90%ATYPICAL10%AVNRT50%LFW40%RFW30%SEPTAL30%WPW30%CC 90%CW 10%TYPICAL90%ATYPICAL10%A FLUTTER10%OTHER10%PTS.PRESENTING WITH SVT2Fitzgerald,et al.,J Electrocardiol.,Vol.29,No.1,Jan.1996,p.1-10.1Fogoros,Electrophysiologic Testing,2nd ed.1995,p 104-107ANTI 10%ORTHO 90%Orthodromic TachycardiaThese terms are only applicable when the patient is in their tachycardia,i.e.during the intrinsic rhythm this patient may be manifest or concealed,but during the tachycardia we define this patient as either antidromic or orthodromic.Antidromic means antegrade conduction(from the atrium to ventricle)occurs down the AP and retrograde conduction(from the ventricle to the atrium)up the normal conduction system(AV node).Orthodromic means antegrade conduction occurs down the normal conduction system and retrograde conduction up the AP.Antidromic TachycardiaAnywhere except here(fibrous trigone)A=atriofascicularB=nodofascicularC=nodoventricular*D=fasciculoventricularE=atrioventricular*first described by MahaimFitzpatrick,et al.,JACC,Vol.23,No.1,Jan.1994,p.110Fusion of the QRS occurs because there is simultaneous conduction down the AV node and accessory pathwayNote the pre-excitation as evidenced by the delta wave,resulting in a short PR intervalDelta WaveShort PR IntervalNormal ECG with no delta wave and a normal PR interval and QRSArruda,et.al.,JCE Vol 9#1 Jan 1998,pp.2-12Arruda,et.al.,JCE Vol 9#1 Jan 1998,pp.2-12More examplesNarrow QRSWide QRSHis and VcaptureV captureonlyVariable Stim-ANarrow QRSWide QRSHis and VcaptureV captureonlyFixed Stim-A 34心律失常发生机制及导管消融适应症(英文)More examplesKuck KH,Cappato R.Catheter Ablation in the Year 2000.Current Opinion in Cardiology 2000;15:29-40.The reentrant circuit involves the Fast Pathway(FP),which enters the compact AV node from the anterior septal region close to the compact AV node,and the Slow Pathway(SP),which is located in the posterior septal region.There are 3 types of AVNRT.In common type AVNRT antegrade conduction is down the SP and retrograde up the FP.In the uncommon type,antegrade conduction is down the FP and retrograde up the SP.In the slow slow type,antegrade conduction is down one SP(a certain bundle of fibers)and retrograde up another SP(a different bundle of fibers).For all three types ablation is performed by ablating the SP,because FP ablation has the risk of complete AV block necessitating pacemaker implantation due to its close proximity to the compact AV node.-Dual pathway physiology;one fast and one slow-Typical(common)AVNRT:antegrade slow,retrograde fast-Atypical AVNRT(uncommon):antegrade fast,retrograde slow-Slow slow AVNRT:antegrade certain slow fibers,retrograde other slow fibers-Jump in AH interval 50 msec during a 10msec decrement in extrastimulus testingCommon(Typical)AVNRTIn common AVNRT,antegrade conduction is down the slow pathway and retrograde up the fast pathway.The earliest atrial activation would be recorded in the anteroseptal region where the fast pathway is located.Also since conduction to the ventricle is down the slow pathway,the AH interval will be prolonged.Uncommon(Atypical)AVNRTIn uncommon AVNRT,antegrade conduction is down the fast pathway and retrograde up the slow pathway.The earliest atrial activation would be recorded in the posteroseptal region where the slow pathway is located.Also since conduction to the ventricle is down the fast pathway,the AH interval will be normal.Slow Slow AVNRTIn Slow Slow AVNRT,antegrade conduction is down some slow pathway fibers and retrograde up other slow pathway fibers.The earliest atrial activation would be recorded in the posteroseptal region where the slow pathway is located.Also since conduction to the ventricle and back to the atrium is via the slow pathway,both the AH&HA intervals will be prolonged.Dual AV Nodal PhysiologyPatients with AVNRT usually demonstrate dual-nodal physiology.Dual AV Nodal Physiology contDual AV nodal physiology-a“jump”in the A-H interval of greater than,or equal to,50 msec in response to a 10 msec decrement in the S1S2 interval;during atrial extra-stimulus testing as the extra-stimulus is introduced(decremented).Clinical Cardiac Electrophysiology:techniques and interpretations,2nd.Ed.Lea and Febiger,1993.page224 Differentiate AVNRT from:-AVRT-AVNRT-Atrial tachycardias-PJRTObjectiveModify the slow pathway of the AV node in order that it will no longer conduct.Slow Pathway Modification Ablation catheter is positioned“anatomically”on the tricuspid valve annulus posterior and inferior to the His bundle at the level of the CS ostium.If unsuccessful,the catheter is moved anterior and superior in a stepwise fashion until successful.RAOLAOSlow Pathway Modification Inability to reinduce tachycardia Loss of dual AVN physiology Prolongation of AH interval Complete heart block*RF Ablation Endpoints*Not a desirable endpoint for slow-pathway ablation.Potential Complications3rd degree AV block-rare when targeting slow pathway10%when targeting fast pathwayOther EP study related complications62心律失常发生机制及导管消融适应症(英文)Easy to diagnoseEasy to treatHigh success rate with RFA64心律失常发生机制及导管消融适应症(英文)