title: A new integrated approach to improve left ventricular electromechanical activation during right ventricular septal pacing.
abstract: OBJECTIVE
  The deleterious effects of apical right ventricular pacing has fostered the utilization of alternative pacing sites. Although right ventricular septal (RVS) sites are commonly used, the results have been controversial because of poor standardization of lead position by fluoroscopy. This study investigated the utility of a new RVS pacing technique based on the combination of fluoroscopy (F), and electrophysiological mapping (F + EP). Left ventricular (LV) electromechanical activation was determined in patients undergoing RVS pacing and the results of the F + EP approach were compared with those derived from standard F alone.
  
  
  RESULTS
  Between December 2008 and November 2010 we enrolled 156 consecutive patients undergoing permanent RVS pacing. The standard F approach was used in 93 patients and the F + EP technique was applied to 63 patients. Electromechanical activation was assessed by: (i) electromechanical latency (EML) interval measured from the QRS onset to the mechanical activation of the basal LV and (ii) intra-LV dyssynchrony measured as the interval from the earliest to the latest LV basal motion. Intra-LV dyssynchrony was found in 46.2% patients in the F group compared with 15.9% in the group F + EP (P < 0.001). The F group demonstrated a significantly higher degree of intra-LV dyssynchrony than F + EP group (43.9 ± 24.3 vs. 26.5 ± 15.4 ms; P < 0.001). The F group exhibited a significantly higher EML duration compared with the F + EP group (215.8 ± 25.3 vs. 195.1 ± 17.4 ms; P < 0.001).
  
  
  CONCLUSIONS
  During RVS pacing, the F + EP approach provides a more physiological LV activation than the standard F technique. The prognostic significance of these short-term findings needs to be correlated with long-term data.
authors.affiliation: Department of Cardiology, Rovigo General Hospital, Via Tre Martiri, 140 45100 Rovigo, Italy. gian.past@libero.it
authors.forename: Gianni
authors.initials: G
authors.lastname: Pastore
authors.forename: Silvio
authors.initials: S
authors.lastname: Aggio
authors.forename: Enrico
authors.initials: E
authors.lastname: Baracca
authors.forename: Gianluca
authors.initials: G
authors.lastname: Rigatelli
authors.forename: Francesco
authors.initials: F
authors.lastname: Zanon
authors.forename: Loris
authors.initials: L
authors.lastname: Roncon
authors.forename: Franco
authors.initials: F
authors.lastname: Noventa
authors.forename: S Serge
authors.initials: SS
authors.lastname: Barold
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004562:Electrocardiography / Q000379:methods; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D005260:Female; D005471:Fluoroscopy; D006346:Heart Septum / Q000503:physiopathology; D006801:Humans; D008297:Male; D013318:Stroke Volume / Q000502:physiology; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000628:therapy*; D016277:Ventricular Function, Left / Q000502:physiology*