Utility of the surface electrocardiogram for.docx

1、Utility of the surface electrocardiogram forUtility of the surface electrocardiogram forconrming right ventricular septal pacing:validation using electroanatomical mappingHaran Burri1*, Chan-il Park1, Marc Zimmermann2, Pascale Gentil-Baron1,Carine Stettler1, Henri Sunthorn1, Giulia Domenichini1, and

2、 Dipen Shah11Cardiology Service, University Hospital, 4, rue Gabrielle-Perret-Gentil, 1211 Geneva 14, Switzerland; and2Cardiology Service, La Tour Hospital, Geneva, SwitzerlandReceived 27 June 2010; accepted after revision 11 August 2010Aims When targeting the interventricular septum during pacemake

3、r implantation, the lead may inadvertently be positionedon the anterior wall due to imprecise uoroscopic landmarks. Surface electrocardiogram (ECG) criteria of the pacedQRS complex (e.g. negativity in lead I) have been proposed to conrm a septal position, but these criteria have notbeen properly val

4、idated. Our aim was to investigate whether the paced QRS complex may be used to conrm septallead position.Methods Anatomical reconstruction of the right ventricle was performed using a NavXwsystem in 31 patients (70+11 years,26 males) to validate pacing sites. Surface 12-lead ECGs were analysed by d

5、igital callipers and compared while pacingfrom a para-Hissian position, from the mid-septum, and from the anterior free wall.Results Duration of the QRS complex was not signicantly shorter when pacing from the mid-septum compared with theother sites. QRS axis was signicantly less vertical during mid

6、-septal pacing (18+518) compared with paraHissian (38+378, P 0.028) and anterior (53+558, P 0.003) pacing, and QRS transition was intermediate(4.8+1.3 vs. 3.8+1.3, P , 0.001, and vs. 5.4+0.9, P 0.045, respectively), although no cut-offs could reliably distinguish sites. A negative QRS or the presenc

7、e of a q-wave in lead I tended to be more frequent with anterior thanwith mid-septal pacing (9/31 vs. 3/31, P 0.2 and 8/31 vs. 1/31, P 1.0, respectively).Conclusion No single ECG criterion could reliably distinguish pacing the mid-septum from the anterior wall. In particular, a negative QRS complex

8、in lead I is an inaccurate criterion for validating septal pacing.- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

9、- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -Keywords Pacing Ventricle Interventricular septum Electrocardiogram Electroanatomical mappingIntroductionFor decades, ventricular pacing has been performed from the apexof the right ventricle (RV), because of ease of implanta

10、tion and leadstability at this site. Conventional RV apical pacing, because of dyssynchronous left ventricular contraction, may have detrimentaleffects on cardiac structure and pump function.1,2Randomizedtrials have reported that RV apical pacing increases incidence ofheart failure and atrial brilla

11、tion.3,4These observations have ledto an interest in alternative right ventricular pacing sites,5such asthe right ventricular outow tract (RVOT) and the mid-septum,to promote more physiological ventricular activation. However,targeting the septum may be technically challenging as it ismainly based o

12、n uoroscopy, without reliable landmarks inpatients with variable chamber size and cardiac orientation. Inthe single study validating lead position using echocardiography,Ng et al.6showed that despite using oblique uoroscopic viewsfor placing the lead on the septum, the nal position was heterogeneous

13、, with the lead being sometimes positioned on the anteriorfree wall or in the anterior outow tract. This is most probably dueto tendency of the lead to fall forward as it is withdrawn from thepulmonary artery during implantation with a standard manuallycurved stylet. Pacing from an anterior site sho

14、uld be avoided asit may result in adverse effects such as reduced left ventricular* Corresponding author. Tel: +41 22 372 72 00; fax: +41 22 372 72 29, Email: haran.burrihcuge.chPublished on behalf of the European Society of Cardiology. All rights reserved. & The Author 2010. For permissions please

15、email: journals.permissionsoxfordjournals.org.Europacedoi:10.1093/europace/euq332Europace Advance Access published September 9, 2010 at Universidade Federal do Amazonas on September 12, 2010 europace.oxfordjournals.org Downloaded from systolic function6or cardiac tamponnade,7and may also carry arisk

16、 of damage to the left anterior descending artery.8Surface electrocardiogram (ECG) criteria of the paced QRScomplex (e.g. a negative QRS complex in lead I) have been proposed to conrm an RVOT septal position.5,9 11However, theECG criteria in these studies have not been properly validated,as actual l

17、ead position was not conrmed by any imaging techniqueother than per-procedural uoroscopy or a simple chest X-ray.Also, it is unknown whether these criteria apply to a mid-septalpacing site, which is lower and more rightward than the RVOTseptum.The aim of our study was to identify ECG criteria during

18、 RVpacing that conrm a mid-septal position and differentiate thissite from the anterior free wall, using electroanatomical mappingto validate pacing sites.MethodsPatient populationA total of 31 consecutive patients from two centres in Geneva(University Hospital and La Tour Hospital), who were schedu

19、ledto undergo radiofrequency ablation of isthmus-dependent atrialutter, were prospectively enrolled in the study. Patient demographics are shown in Table 1.All patients gave informed consent to participate in the study,which was approved by the Institutional Ethics Committee.Mapping protocolPatients

20、 were studied in a fasting and sedated state. Two catheterswere introduced percutaneously through the right femoral vein. A6-French quadripolar diagnostic catheter (Bard Electrophysiology,Lowell, MA, USA) was advanced to the right atrium and anirrigated-tip 3.5 mm ablation catheter (ThermoCool F cur

21、ve, Biosense Webster, Diamond Bar, CA, USA or Therapy Cool Path FLcurve, St Jude Medical, St Paul, MN, USA) was used for performingcavo-tricuspid isthmus ablation. After obtaining bidirectional blockof the cavo-tricuspid isthmus, anatomical reconstruction of the RVwas performed using the EnSite NavX

22、wsystem (St Jude Medical).The quadripolar diagnostic catheter was used as the reference andpositioned in a stable position in the right atrium (rather than inthe ventricle, so as to avoid displacement when manipulating themapping catheter), with creation of a shadow to monitor displacement. The abla

23、tion catheter was manoeuvred in the entire RVfor geometrical reconstruction. The plane of the pulmonaryvalve was dened by advancing the mapping catheter in theRVOT until no discrete bipolar electrograms were recorded inthe distal electrode, and the tricuspid valve was dened by equalamplitudes of atr

24、ial and ventricular electrograms. The His bundlewas annotated at the onset of mapping, and its location checkedat the end of the pacing protocol, in order to verify the absenceof reference shift during the study (in addition to verifying theshadow of the quadripolar reference catheter).After geometr

25、ical reconstruction of the RV, pace-mapping ofthree sites was performed (Figure 1): para-Hissian (about 1 cminto the ventricle from the His), the mid-septum (at the centreof the septum in the right oblique anterior view, roughly halfwayalong the line drawn between the His and the apex, and caudalto

26、the level of the His), and the RV anterior free wall (close tothe anteroseptal sulcus, where pacing leads are often inadvertentlyplaced). Anatomical tagging was performed at each site and theventricle was paced at 80 bpm for 1020 captured beats, duringwhich a 12-lead digital ECG was continuously rec

27、orded using theBardwelectrophysiology bay (Figure 2).Electrocardiogram analysisThe 12-lead ECG derived from each pacing site was analysedoff-line using the digital callipers of the Bardwelectrophysiologybay. The following parameters were analysed:(1) QRS duration(2) Amplitudes of Q, R, and S waves i

28、n all limb leads. The net QRSamplitude in each lead was calculated as R2(Q + S), and wasused to dene whether the QRS was positive or negative inthat lead, and for calculation of the QRS axis.(3) QRS axis calculated using net QRS amplitudes in leads I andaVF with the following formula that we conceiv

29、ed: axis 57.3*ATAN(AVF/I). The value was manually adjusted foraxes of +908 or 2908 in case of a perfectly isoelectric QRScomplex in lead I (as the formula yields an error for lead I 0), and corrected by adding 1808 to the result if the QRSwas negative in lead I. A visually estimated QRS axis was als

30、onoted to serve as a control.(4) Presence of a q-wave or a negative QRS in lead I (which haspreviously been attributed to septal pacing9,12)(5) Presence of QRS notching in the limb leads (pacing of free wallsites has been reported to result in notching in the inferiorleads9,12)(6) QRS transition in

31、the precordial leads (a transition at or laterthan V4 has been shown to distinguish RVOT free wall sitesfrom an RVOT septal site12). Transition was dened as thelead with R . (Q + S) amplitude.The measurements were performed by a single observer (C.-I.P.)and veried by a second investigator (H.B.). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Table 1 Patients demographicsAll patients (n 5 31)Age (years) 70+11Male/Female 26/5Underlying heart diseaseIschaemic 9Dil