title: The Right to Left Atrial Volume Ratio Predicts Outcomes after Circumferential Pulmonary Vein Isolation of Longstanding Persistent Atrial Fibrillation.
abstract: BACKGROUND
  We aimed to identify the predictors of clinical outcomes after circumferential pulmonary vein isolation (CPVI) without any substrate modification for longstanding persistent atrial fibrillation (LSP-AF).
  
  
  METHODS
  This study retrospectively analyzed 70 consecutive LSP-AF patients who underwent an initial CPVI and were followed-up for more than 1 year. The right and left atrial volumes indexed to the body surface areas (right atrial volume index [RAVI] and left atrial volume index [LAVI]) were determined by preacquired contrast-enhanced computed tomography (CT). The %RAVI/LAVI was obtained as 100 × RAVI/LAVI.
  
  
  RESULTS
  During a median follow-up period of 15 months (interquartile range, 13-19 months), 21 patients (30%) had arrhythmia recurrences after the CPVI. Antiarrhythmic drugs were continued in 34 patients (48%). In the Cox proportional hazard model, the %RAVI/LAVI was a significant positive predictor of arrhythmia recurrences (hazard ratio, 1.048; P = 0.039). A receiver-operating characteristic analysis demonstrated that at an optimal cutoff of 100.1 for the %RAVI/LAVI, the sensitivity and specificity for predicting arrhythmia recurrences were 85.7% and 71.4%, respectively. The Kaplan-Meier analysis showed that arrhythmia recurrences were less frequent in patients with a %RAVI/LAVI of <100.1 than in those with a %RAVI/LAVI of ≥100.1 (P < 0.0001), and the arrhythmia-free survival rate at 12 months was 89.7% and 45.2%, respectively.
  
  
  CONCLUSIONS
  The ratio of the RAVI to LAVI on CT may be a useful predictor of clinical outcomes after CPVI of LSP-AF. LSP-AF patients with a less predominant right atrial enlargement relative to the left atrial enlargement may be good candidates for successful treatment with CPVI alone as the ablation strategy for LSP-AF.
authors.affiliation: Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan.
authors.forename: Takehito
authors.initials: T
authors.lastname: Sasaki
authors.affiliation: Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan.
authors.forename: Kohki
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan.
authors.forename: Shigeto
authors.initials: S
authors.lastname: Naito
authors.affiliation: Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Minami
authors.affiliation: Division of Radiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Koyama
authors.affiliation: Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Yamashita
authors.affiliation: Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Kumagai
authors.affiliation: Division of Cardiology, Gunma Prefectural Cardiovascular Center, Maebashi City, Gunma, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Oshima
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000209:etiology; D001281:Atrial Fibrillation / Q000601:surgery*; D002306:Cardiac Volume; D017115:Catheter Ablation; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D016016:Proportional Hazards Models; D011667:Pulmonary Veins / Q000601:surgery*; D012372:ROC Curve; D012008:Recurrence; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: atrial fibrillation; atrial volume; multidetector computed tomography; pulmonary vein isolation; radiofrequency catheter ablation