title: Detecting the Elusive P-Wave: A New ECG Lead to Improve the Recording of Atrial Activity.
abstract: OBJECTIVE
  In this study, we report on a lead selection method that was developed to detect the optimal bipolar electrode placement for recording of the P-wave.
  
  
  METHODS
  The study population consisted of 117 lead body surface potential maps recorded from 229 healthy subjects. The optimal bipolar lead was developed using the training set (172 subjects) then extracted from the testing dataset (57 subjects) and compared to other lead systems previously reported for improved recording of atrial activity. All leads were assessed in terms of P-wave, QRS, and STT root mean square (RMS). The P/QRST RMS ratio was also investigated to determine the atrioventricular RMS ratio. Finally, the effect of minor electrode misplacements on the P-lead was investigated.
  
  
  RESULTS
  The P-lead discovered in this study outperformed all other investigated leads in terms of P-wave RMS. The P-lead showed a significant improvement in median P-wave RMS (93 versus 72 μV, p < 0.001) over the next best lead, Lead II. An improvement in QRS and STT RMS was also observed from the P-lead in comparison to lead II (668 versus 573 μV, p < 0.001) and (327 versus 196 μV, p < 0.001). Although P-wave RMS was reduced by incorrect electrode placement, significant improvement over Lead II was still evident.
  
  
  CONCLUSIONS
  The P-lead improves P-wave RMS signal strength over all other investigated leads. Also the P-lead does not reduce QRS and STT RMS making it an appropriate choice for atrial arrhythmia monitoring.
  
  
  CONCLUSIONS
  Given the improvement in signal-to-noise ratio, an improvement in algorithms that rely on P-wave analysis may be achieved.
authors.forename: Alan
authors.initials: A
authors.lastname: Kennedy
authors.forename: Dewar D
authors.initials: DD
authors.lastname: Finlay
authors.forename: Daniel
authors.initials: D
authors.lastname: Guldenring
authors.forename: Raymond R
authors.initials: RR
authors.lastname: Bond
authors.forename: James
authors.initials: J
authors.lastname: McLaughlin
mesh_terms: D016275:Atrial Function / Q000502:physiology*; D018780:Body Surface Potential Mapping; D004562:Electrocardiography / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D012815:Signal Processing, Computer-Assisted; D059629:Signal-To-Noise Ratio