title: Anteroseptal basal right ventricular entrainment is simple and superior to apical entrainment in identifying mechanism of supraventricular tachycardia.
abstract: BACKGROUND
  Differentiation between atrioventricular nodal reentry tachycardia (AVNRT) and atrioventricular reentrant tachycardia (AVRT) can be sometimes challenging. Apical right ventricular (RV) entrainment can help in differentiation; however, it has some fallacies. We thought to compare the accuracy of anteroseptal basal RV entrainment to RV apical entrainment in identifying the mechanism of supraventricular tachycardia (SVT).
  
  
  METHODS
  Forty-two consecutive patients with SVT who underwent catheter ablation were prospectively studied. Apical RV entrainment was performed initially followed by basal entrainment from the anteroseptal basal RV avoiding His or atrial capture. Postpacing interval (PPI), PPI-tachycardia cycle length (TCL), corrected PPI-TCL, and stimulus-atrial minus ventricular-atrial (VA) intervals were measured.
  
  
  RESULTS
  Entrainment was achieved from both sites of RV in 34 patients (ten men; mean age 42 ± 15 years), 20 with typical AVNRT, 1 with atypical AVNRT, and 13 with AVRT (eight left sided, four right sided, and one septal accessory pathways). PPI-TCL, corrected PPI (cPPI)-TCL, and stimulus-atrial-VA intervals were significantly longer with basal entrainment in AVNRT (171 ± 30 vs. 153 ± 22 ms (p = 0.003), 148 ± 21 vs. 131 ± 20 ms (p = 0.002), and 145 ± 17 vs. 136 ± 15 ms (p = 0.005), respectively). Receiver-operating characteristic curves showed higher AUC for the above parameters with basal entrainment compared to apical entrainment. Cutoff values of basal PPI-TCL of >110 ms and cPPI-TCL of >95 ms had better sensitivities (100 % for both vs. 95 and 90 %, respectively, for apical values) and specificities (85 and 92 % vs. 77 and 92 %, respectively) for diagnosis of AVNRT.
  
  
  CONCLUSIONS
  Basal RV entrainment from the anteroseptal basal RV is a simple maneuver that is superior to apical ventricular entrainment in identifying the mechanism of SVT.
authors.affiliation: Electrophysiology and Pacing Service, Department of Cardiovascular Medicine, Cairo University, Cairo, Egypt, amirabdelwahab@gmail.com.
authors.forename: Amir M
authors.initials: AM
authors.lastname: Abdelwahab
authors.forename: Dhaifallah Y
authors.initials: DY
authors.lastname: Yahya
authors.forename: Essam B
authors.initials: EB
authors.lastname: Eweis
authors.forename: Mohamed Z
authors.initials: MZ
authors.lastname: El Ramly
mesh_terms: D000328:Adult; D018780:Body Surface Potential Mapping / Q000379:methods*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D003937:Diagnosis, Differential; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013617:Tachycardia, Supraventricular / Q000175:diagnosis* / Q000601:surgery*; D016896:Treatment Outcome