title: The role of empiric superior vena cava isolation in atrial fibrillation: a systematic review and meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  It is not clear whether additional empiric superior vena cava isolation (SVCI) to pulmonary vein isolation (PVI) results in low recurrences of atrial fibrillation. We aimed to perform a systematic review and meta-analysis of all randomized controlled trials (RCTs) that evaluated role of empiric SVCI in atrial fibrillation ablation.
  
  
  METHODS
  We searched PubMed, EMBASE, Cochrane, Scopus, and relevant references for RCTs (inception April 15, 2016 without language restrictions) and performed meta-analysis using random effects model. Recurrence rates of atrial fibrillations, procedural times, fluoroscopic times, and adverse events were the measured outcomes.
  
  
  RESULTS
  Three RCTs with a total population of 526 were analyzed. There was no difference in the recurrence rate between PVI plus SVCI versus PVI alone when comparison was made across all types of AF (39 vs 60; odds ratio 0.68; 95 % CI 0.43-1.07; P = 0.73; I2= 0 %). When analysis was restricted only to paroxysmal AF, there was a trend towards low recurrence rate in combination group without statistical significance (19 vs 35, OR 0.54; 95 % CI 0.29-1.00; P = 0.05; I2= 0). Similarly, no difference was noted between two groups in procedural (weighted mean difference [WMD] 10.12; 95 % CI -9.84 to 30.08; P = 0.32; I2= 85 %) and fluoroscopic time (WMD 4.66; 95 % CI -0.92 to 10.25; P = 0.1; I2= 94). Adverse events were similar in both groups.
  
  
  CONCLUSIONS
  Empiric SVCI does not provide additional benefit to PVI alone for atrial fibrillation ablation.
authors.affiliation: University of New England, LRGHealthcare, 80 Highland Street, Laconia, NH, 03246, USA. ssharma@lrgh.org.
authors.forename: Sharan Prakash
authors.initials: SP
authors.lastname: Sharma
authors.affiliation: Clinical Cardiac Electrophysiology, Section of Cardiology, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA.
authors.forename: Rajbir S
authors.initials: RS
authors.lastname: Sangha
authors.affiliation: University of New England, LRGHealthcare, 80 Highland Street, Laconia, NH, 03246, USA.
authors.forename: Khagendra
authors.initials: K
authors.lastname: Dahal
authors.affiliation: Division of Cardiology, Albert Einstein Medical Center, Philadelphia, PA, USA.
authors.forename: Parasuram
authors.initials: P
authors.lastname: Krishnamoorthy
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000517:prevention & control / Q000601:surgery*; D017115:Catheter Ablation / Q000706:statistics & numerical data*; D015897:Comorbidity; D005260:Female; D006329:Heart Conduction System / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology* / Q000517:prevention & control; D015995:Prevalence; D011667:Pulmonary Veins / Q000601:surgery*; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D012008:Recurrence; D012307:Risk Factors; D016896:Treatment Outcome; D014683:Vena Cava, Superior / Q000601:surgery*
keywords: Ablation; Atrial fibrillation; Pulmonary vein isolation; Superior vena cava isolation