title: Clinical significance of prolonged P wave width after right atrial appendage pacing in sick sinus syndrome.
abstract: The present study investigated both the clinical significance of atrial fibrillation (AF) before right atrial appendage (RAA) pacing and the influence of prolonged P wave on AF occurrence in RAA-paced patients with sick sinus syndrome (SSS). Fifty-seven patients (age 68+/-10 years; 19 men, 38 women) with SSS who underwent RAA pacing were divided into 2 groups: 23 patients without AF before pacing (I + II; Rubenstein I or II) and 34 patients with AF before pacing (III; Rubenstein III). The P wave duration in intrinsic rhythm and with RAA pacing were measured on the standard electrocardiography in leads II and V(1) with the use of a digitizing tablet. Group III was further subdivided into 2 groups: 20 patients (IIIb) with a paced P wave >130 ms in both leads II and V(1) and the other 14 patients (IIIa). The duration of the intrinsic P wave in leads II and V(1) was significantly greater in group III than in group I + II (119+/-20 vs 108+/-21 ms, p=0.0417, 106+/-16 vs 95+/-21 ms, p=0.0258, respectively). During the follow-up of 40+/-21 months, AF recurrence was significantly higher in group IIIb than in groups IIIa and I + II (17/20 vs 5/14 vs 2/23 p<0.0001). A few occurrences of AF were observed by conventional RAA pacing in patients without AF before pacing. However, SSS with AF before pacing caused a significant intra-atrial conduction disturbance and a high incidence of AF recurrence after implantation of RAA pacing, especially in patients with a prolonged paced P wave, in whom new pacing modalities may be needed to shorten paced P wave duration and prevent AF.
authors.affiliation: Department of Cardiology, Saiseikai Kurihashi Hospital, Tokyo, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Endoh
authors.forename: Ayako
authors.initials: A
authors.lastname: Nakamura
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Suzuki
authors.forename: Masayuki
authors.initials: M
authors.lastname: Mizuno
authors.forename: Ayako
authors.initials: A
authors.lastname: Takara
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Ota
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kasanuki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D020517:Atrial Appendage / Q000503:physiopathology*; D001281:Atrial Fibrillation / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D001919:Bradycardia / Q000503:physiopathology / Q000517:prevention & control; D002304:Cardiac Pacing, Artificial / Q000379:methods; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012804:Sick Sinus Syndrome / Q000150:complications / Q000503:physiopathology* / Q000628:therapy