室上性心动过速学习教案

1、会计学1室上性心动过速室上性心动过速第一页，共38页。IntrogynDiagnosisnTreatmentnAcutenChronicnExcluding Atrial Fibrillation and Flutter第1页/共37页第二页，共38页。Epidresenting EDsnOrejarena, J AM Coll Card. 1998;31:150-7nMean age of onset 57 yearsnRanging from infancy to 90 years oldnIn this study, younger patients (mean of 37) were

2、more likely to present to the ED and less likely to have structural heart disease(69%)第2页/共37页第三页，共38页。Mecanisms leading to all TachyarrhythmiasnImpaired impulse initiationnproblems of abnormal automaticitynAbnormal impulse conductionnRe-entrant impulses第3页/共37页第四页，共38页。Locatioythmia arising from AV

3、 node or abovenImpulses can be transmitted from several loci nSinus NodenAtriumnAV NodenPoint of origin has implications for treatment第4页/共37页第五页，共38页。Aasic forms of SVTs arising from the AV nodenAtrioventricular Node Reciprocating Tachycardia(AVNRT)nAtrioventricular Reciprocating Tachycardia(AVRT)n

4、Both are dependent on the AV node for maintenance of the Reentry circuit第5页/共37页第六页，共38页。Reentrbranch第6页/共37页第七页，共38页。Aore than half of the cases of PSVTsnFast and slow conducting fibers from the atrium to the AV node make up reentry circuitnFast fibers have a long refractory periodnSlow fibers have

5、 a shorter refractory period第7页/共37页第八页，共38页。AVNed by a PACnFast fibers are still refractory from previous impulsenImpulse conducted down Slow fibers and retrogradely up fast fibersnThis slow-fast mechanism accounts for 90% of AVNRTs第8页/共37页第九页，共38页。AVNRHeart 2002;87:299304第9页/共37页第十页，共38页。n accesso

6、ry pathwaynWolf-Parkinson-White syndromenCan have either Orthodromic or Antidromic conduction through the AV nodenMost common is Orthodromic with retrograde conduction through the accessory pathway第10页/共37页第十一页，共38页。AVRHeart 2002;87:299304第11页/共37页第十二页，共38页。AVRcipitated by a PAC or PVCnDependent on

7、AV node for continued reentry第12页/共37页第十三页，共38页。VRT arise due to reentrant mechanismnBoth are dependent on the AV node for their maintenancenDrugs that work on the AV node should break the circuit第13页/共37页第十四页，共38页。Atrial Tal tachycardianSingle P wave morphologynMay be due to either abnormal automat

8、icity or reentry mechanismsnSometimes mistaken for Flutter although rate is usually less than 250nRare第14页/共37页第十五页，共38页。Atrial Tachnt.)rial tachycardianDue to increased automaticitynMultiple atrial sites of impulse initiationnUsually not ParoxysmalnMore common than unifocal第15页/共37页第十六页，共38页。Atrial

9、 Tachnt.)ardias are not dependent on the AV node for their propagationnAV blocking agents will slow conduction through the AV node but not break them第16页/共37页第十七页，共38页。Sinus Tanus TachycardianInappropriate Sinus TachycardianReentrant Sinus TachycardianMicro reentry circuit within the SA node第17页/共37

10、页第十八页，共38页。Diacal ExamnEKG第18页/共37页第十九页，共38页。ul analysis of EKG 20% of SVTs are incorrectly diagnosednCertain features can lead to the diagnosis of particular SVTs第19页/共37页第二十页，共38页。Atrial Tl Rate usually 250 helping to distinguish from A. FlutternRegular Rhythm nPositive P waves in inferior leads b

11、efore each QRS if high atrial originnP wave will have different morphology from Sinus P wavesnRhythm terminates with QRS complex第20页/共37页第二十一页，共38页。第21页/共37页第二十二页，共38页。Atrial Tegular rhythmnGenerally slower rates than other SVTsnGenerally more incessant in naturenRequires 3 distinct P wave morpholog

12、ies with isoelectric periods between them.第22页/共37页第二十三页，共38页。第23页/共37页第二十四页，共38页。A-180nRegularnP waves generally hidden within the QRS complexnMay see a pseudo r in V1 or pseudo S in inferior leadsnpseudo r: sens. 58%, spec. 91%npseudo S: sens. 14%, spec. 100%nJ. Am. Coll. Card 1993;21(1):85-9第24页/

13、共37页第二十五页，共38页。第25页/共37页第二十六页，共38页。ay see widened QRS if antegrade conduction down accessory pathway or signs of preexcitation in sinus (delta wave)nretrograde P waves follow QRSnQRS alternans第26页/共37页第二十七页，共38页。第27页/共37页第二十八页，共38页。第28页/共37页第二十九页，共38页。Goals ontry circuitnControl ratenChronicnPrevent

14、 recurrences第29页/共37页第三十页，共38页。AardiovertnVagal ManeuversnDiagnostic and Therapeuticn63% responded in a series by Mehta with younger patients more likely to respontnLancet 1988, May:1181-5n30% response in series by MullernAm J of Card 1994;74:500-503第30页/共37页第三十一页，共38页。Adeestigated in the 1980snBeca

15、me the first line treatment in the early 1990snMulticenter placebo-controlled trial by DiMarco showed that Adenosine was equally effective to Verapamil with better side effect profilenAnnals of Internal Med 1990;113:104-110第31页/共37页第三十二页，共38页。Adenose receptors causing hyperpolarization of the cellnE

16、xtremely short half life limits side effectsnMaybe ineffective in patients taking methylxanthinesnHas replaced Ca channel blockers that had previously been the first line treatmentnWill break most reentrant SVTs dependent on the AV node第32页/共37页第三十三页，共38页。Chronie severity and frequency of symptomsnD

17、rug TherapynCa Channel blockers, Beta blockers, Dig, Flecainide, PropafenonenNot entirely effective and side effectsnCatheter Ablation第33页/共37页第三十四页，共38页。Catheteatment of choice for persistently symptomatic patientsnThose with WPW may be referred for ablation even without persistent symptomsnSuccess rates of about 96% have been reportednAbout 1% risk of 2nd or 3rd degree AV Block第34页/共37页第三十五页，共38页。Suocation of SVT has implications for treatmentnEKG holds clues for the type of SVT, although 20% will not be discernable by the EKGnAdenosine is the mainst