室上性心動過速學(xué)習(xí)教案

1、會計(jì)學(xué)1室上性心動過速室上性心動過速第一頁，共38頁。IntrogynDiagnosisnTreatmentnAcutenChronicnExcluding Atrial Fibrillation and Flutter第1頁/共37頁第二頁，共38頁。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頁/共37頁第三頁，共38頁。Mecanisms leading to all TachyarrhythmiasnImpaired impulse initiationnproblems of abnormal automaticitynAbnormal impulse conductionnRe-entrant impulses第3頁/共37頁第四頁，共38頁。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頁/共37頁第五頁，共38頁。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頁/共37頁第六頁，共38頁。Reentrbranch第6頁/共37頁第七頁，共38頁。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頁/共37頁第八頁，共38頁。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頁/共37頁第九頁，共38頁。AVNRHeart 2002;87:299304第9頁/共37頁第十頁，共38頁。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頁/共37頁第十一頁，共38頁。AVRHeart 2002;87:299304第11頁/共37頁第十二頁，共38頁。AVRcipitated by a PAC or PVCnDependent on

7、AV node for continued reentry第12頁/共37頁第十三頁，共38頁。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頁/共37頁第十四頁，共38頁。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頁/共37頁第十五頁，共38頁。Atrial Tachnt.)rial tachycardianDue to increased automaticitynMultiple atrial sites of impulse initiationnUsually not ParoxysmalnMore common than unifocal第15頁/共37頁第十六頁，共38頁。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頁/共37頁第十七頁，共38頁。Sinus Tanus TachycardianInappropriate Sinus TachycardianReentrant Sinus TachycardianMicro reentry circuit within the SA node第17頁/共37

10、頁第十八頁，共38頁。Diacal ExamnEKG第18頁/共37頁第十九頁，共38頁。ul analysis of EKG 20% of SVTs are incorrectly diagnosednCertain features can lead to the diagnosis of particular SVTs第19頁/共37頁第二十頁，共38頁。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頁/共37頁第二十一頁，共38頁。第21頁/共37頁第二十二頁，共38頁。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頁/共37頁第二十三頁，共38頁。第23頁/共37頁第二十四頁，共38頁。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頁/

13、共37頁第二十五頁，共38頁。第25頁/共37頁第二十六頁，共38頁。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頁/共37頁第二十七頁，共38頁。第27頁/共37頁第二十八頁，共38頁。第28頁/共37頁第二十九頁，共38頁。Goals ontry circuitnControl ratenChronicnPrevent

14、 recurrences第29頁/共37頁第三十頁，共38頁。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頁/共37頁第三十一頁，共38頁。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頁/共37頁第三十二頁，共38頁。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頁/共37頁第三十三頁，共38頁。Chronie severity and frequency of symptomsnD

17、rug TherapynCa Channel blockers, Beta blockers, Dig, Flecainide, PropafenonenNot entirely effective and side effectsnCatheter Ablation第33頁/共37頁第三十四頁，共38頁。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頁/共37頁第三十五頁，共38頁。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