title: Interatrial septum pacing decreases atrial dyssynchrony on strain rate imaging compared with right atrial appendage pacing.
abstract: BACKGROUND
  Interatrial septum pacing (IAS-P) decreases atrial conduction delay compared with right atrial appendage pacing (RAA-P). We evaluate the atrial contraction with strain rate of tissue Doppler imaging (TDI) during sinus activation or with IAS-P or RAA-P.
  
  
  METHODS
  Fifty-two patients with permanent pacemaker for sinus node disease were enrolled in the study. Twenty-three subjects were with IAS-P and 29 with RAA-P. The time from end-diastole to peak end-diastolic strain rate was measured and corrected with RR interval on electrocardiogram. It was defined as the time from end-diastole to peak end-diastolic strain rate (TSRc), and the balance between maximum and minimum TSRc at three sites (ΔTSRc) was compared during sinus activation and with pacing rhythm in each group.
  
  
  RESULTS
  There were no significant differences observed in general characteristics and standard echocardiographic parameters except the duration of pacing P wave between the two groups. The duration was significantly shorter in the IAS-P group compared with the RAA-P group (95 ± 34 vs 138 ± 41; P = 0.001). TSRc was significantly different between sinus activation and pacing rhythm (36.3 ± 35.7 vs 61.6 ± 36.3; P = 0.003) in the RAA-P group, whereas no significant differences were observed in the IAS-P group (25.4 ± 12.1 vs 27.7 ± 14.7; NS). During the follow-up (mean 2.4 ± 0.7 years), the incidence of paroxysmal atrial fibrillation (AF) conversion to permanent AF was not significantly different between the two groups.
  
  
  CONCLUSIONS
  IAS-P decreased the contraction delay on atrial TDI compared to RAA-P; however, it did not contribute to the reduction of AF incidence in the present study.
authors.affiliation: Cardiovascular Division, Osaka Minami Medical Center, Kawachinagano, Osaka, Japan. yasuoka@ommc-hp.jp
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Yasuoka
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Abe
authors.forename: Seiko
authors.initials: S
authors.lastname: Umekawa
authors.forename: Keiko
authors.initials: K
authors.lastname: Katsuki
authors.forename: Norio
authors.initials: N
authors.lastname: Tanaka
authors.forename: Ryo
authors.initials: R
authors.lastname: Araki
authors.forename: Takahiro
authors.initials: T
authors.lastname: Imanaka
authors.forename: Ryo
authors.initials: R
authors.lastname: Matsutera
authors.forename: Daisuke
authors.initials: D
authors.lastname: Morisawa
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kitada
authors.forename: Susumu
authors.initials: S
authors.lastname: Hattori
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Noda
authors.forename: Hidenori
authors.initials: H
authors.lastname: Adachi
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Sasaki
authors.forename: Kunio
authors.initials: K
authors.lastname: Miyatake
mesh_terms: D000368:Aged; D020517:Atrial Appendage / Q000000981:diagnostic imaging / Q000503:physiopathology*; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000517:prevention & control*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006346:Heart Septum / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D016896:Treatment Outcome