title: Blanking Period Phenomenon After a Second Atrial Fibrillation Ablation Session: The Application and Factors Related to It.
abstract: The concept of a 3-month blanking period is widely accepted after the first radiofrequency catheter ablation (RFCA) session for atrial fibrillation (AF). We sought to investigate whether this phenomenon was also observed after a 2nd session, and which factors were related to it.
  
  
  
  We conducted a prospective observational study including all AF patients who underwent RFCA since 2010. The patients who underwent a second RFCA were followed without any antiarrhythmic drugs. Their clinical background, laboratory data, echocardiographic parameters, ablation procedures, and arrhythmia recurrences were analyzed. Recurrences were classified into early period recurrences (EPRs) and late period recurrences (LPRs) recorded within and after the first 3 months postablation, respectively. Among 925 patients who underwent an initial AF ablation, 2nd sessions were performed in 250 patients, and EPRs and LPRs occurred in 53 (21.2%) and 54 (21.6%) patients, respectively. Although EPRs were an independent predictor of LPRs (hazard ratio [HR], 8.01; 95% confidence interval [CI] 4.03-15.93, P < 0.001), 20 of the patients with EPRs (37.7%) did not experience LPRs, supporting the concept of a blanking period. Among 53 patients with EPRs, the E/E' ratio on echocardiography (HR, 1.156; 95% CI 1.00-1.33, P = 0.04) was an independent predictor of LPRs, while other parameters including the maximum serum C-reactive protein level after the session and the ablation procedure details were not.
  
  
  
  A 3-month blanking period was also applicable after the 2nd AF ablation session. This phenomenon was related to a lower left atrial pressure demonstrated by the E/E' ratio.
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Yuhi
authors.initials: Y
authors.lastname: Fujimoto
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Meiso
authors.initials: M
authors.lastname: Hayashi
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Yu-Ki
authors.initials: YK
authors.lastname: Iwasaki
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Yodogawa
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Teppei
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Ippei
authors.initials: I
authors.lastname: Tsuboi
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Izumi
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Oka
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Hagiwara
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Miyauchi
authors.affiliation: Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Shimizu
mesh_terms: D000200:Action Potentials; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D016279:Atrial Function, Left; D062185:Atrial Pressure; D017115:Catheter Ablation / Q000009:adverse effects*; D018572:Disease-Free Survival; D004452:Echocardiography; D005260:Female; D006325:Heart Atria / Q000503:physiopathology / Q000601:surgery*; D006339:Heart Rate; D006801:Humans; D007564:Japan; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011667:Pulmonary Veins / Q000503:physiopathology / Q000601:surgery*; D012008:Recurrence; D012086:Reoperation; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
keywords: 2nd session; E/E’ ratio; atrial fibrillation; blanking period; echocardiography; radiofrequency catheter ablation