title: The combined use of esophageal electrocardiogram and multiple right parasternal chest leads in the diagnosis of PSVT and determination of accessory pathways involved: a new simple noninvasive approach.
abstract: BACKGROUND
  Paroxysmal Supraventricular Tachycardia (PSVT) resulting from any cause can at times lead to diagnostic difficulty mainly when due to AVNRT and AVRT. In this study we used a non-invasive approach using esophageal ECG (ECGe) and ECG derived from the various right parasternal chest leads (RPCL) to correctly diagnose the type of PSVT as well the accessory pathways involved in AVRT.
  
  
  RESULTS
  We studied a total of 161 patients (89 male) all having a history of palpitation. All the patients underwent routine 12 lead ECG, ECGe, RPCL and electrophysiologic study. With use of ECGe and RPCL, 71 (44.1%) were diagnosed as having AVNRT and 90 (55.9%) having AVRT with various accessory pathways compared to only 49 (30.4%) and 22 (13.7%) respectively with routine 12 lead ECG. With combined ECGe and RPCL, 80 (49.7%) showed accessory pathway in the left free wall, 4 (2.5%) showed in the right free wall, 6 (3.7%) septal accessory pathway, 60 (37.3%) in the anterior wall and 30 (18.6%) in the posterior wall. In comparison, EPS could show accessory pathways in the left free wall in 81 (50.3%), in the right free wall in 5 (3.1%), in the septum in 4 (2.5%), in the anterior wall in 53 (32.9%) and in the posterior wall in 37 (23.0%) out of the 161 patients.
  
  
  CONCLUSIONS
  ECGe+RPCL can be used as a reliable noninvasive diagnostic tool to identify the nature of tachycardia and the pathways involved in the reentrant ring of PSVT especially in those with multiple atrioventricular accessory pathways or a combination of atrioventricular accessory pathways and dual atrioventricular nodal pathway.
authors.affiliation: Institute of Cardiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jie-Fang Avenue, Wuhan 430022, Hubei Province, PR China. lyush@hotmail.com
authors.forename: Yushu
authors.initials: Y
authors.lastname: Li
authors.forename: Liya
authors.initials: L
authors.lastname: Rao
authors.forename: Sajan Gopal
authors.initials: SG
authors.lastname: Baidya
authors.forename: Yibo
authors.initials: Y
authors.lastname: Feng
authors.forename: Jiaming
authors.initials: J
authors.lastname: Zhang
authors.forename: Junguo
authors.initials: J
authors.lastname: Yang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D004562:Electrocardiography / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D004947:Esophagus; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013614:Tachycardia, Paroxysmal / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D013617:Tachycardia, Supraventricular / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology