title: Left Atrial Substrate Modification Targeting Low-Voltage Areas for Catheter Ablation of Atrial Fibrillation: A Systematic Review and Meta-Analysis.
abstract: BACKGROUND
  This meta-analysis aims to assess the impact of a voltage-guided substrate modification by targeting low-voltage area (LVA) in addition to pulmonary vein isolation (PVI) in patients undergoing catheter ablation for atrial fibrillation (AF).
  
  
  METHODS
  MEDLINE/PubMed, Cochrane Library, and references reporting AF ablation and "voltage* OR substrate* OR fibrosis OR fibrotic area*" were screened and studies included if matching inclusion and exclusion criteria.
  
  
  RESULTS
  Six studies were included. Patients enrolled were 885 (517 in the study group and 368 in the control group). Median age was 60 years; 92% had nonparoxysmal AF. At a mean follow-up of 17 months, 70% of patients in the study group vs. 43% in the control group were free from AF/atrial tachycardia (AT) recurrences (odds ratio [OR] = 3.41, 95% confidence interval [CI] 2.22-5.24). LVA ablation in addition to PVI was more effective than PVI alone and PVI + conventional wide empirical ablation (70% vs. 43%, OR = 3.41, 95% CI 2.22-5.24), without increasing the adverse event rate (2.5% vs. 6%, OR = 0.43, 95% CI 0.15-1.26). Compared to PVI + conventional wide empirical ablation, LVA ablation reduced the occurrence of postablation AT (14% vs. 46%, OR = 0.16, 95% CI 0.07-0.37), procedure time (176 min vs. 220 min, OR = 0.36, 95% CI 0.24-0.56), fluoroscopy time (25 min vs. 31 min, OR = 0.22, 95% CI 0.12-0.39), and radiofrequency time (55 min vs. 90 min, OR = 0.49, 95% CI 0.27-0.90).
  
  
  CONCLUSIONS
  A voltage-guided substrate modification by targeting LVA in addition to PVI is more effective, safer, and holds a lower proarrhythmic potential than conventional ablation approaches. Further randomized studies are necessary to confirm these findings.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, S. Andrea Hospital, Vercelli, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Blandino
authors.affiliation: Division of Cardiology, Mauriziano Umberto I Hospital, Turin, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Bianchi
authors.affiliation: Division of Cardiology, Mauriziano Umberto I Hospital, Turin, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Grossi
authors.affiliation: Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Latina, Italy.|Department of AngioCardioNeurology, IRCCS Neuromed, Pozzilli, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Biondi-Zoccai
authors.affiliation: Division of Cardiology, Mauriziano Umberto I Hospital, Turin, Italy.
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Conte
authors.affiliation: Division of Cardiology, Department of Medical Sciences, Città della Salute e della Scienza, University of Turin, Turin, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Gaido
authors.affiliation: Division of Cardiology, Department of Medical Sciences, Città della Salute e della Scienza, University of Turin, Turin, Italy.
authors.forename: Fiorenzo
authors.initials: F
authors.lastname: Gaita
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Cardinal Gugliemo Massaia Hospital, Asti, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Scaglione
authors.affiliation: Division of Cardiology, Department of Internal Medicine, S. Andrea Hospital, Vercelli, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Rametta
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery*; D018780:Body Surface Potential Mapping / Q000379:methods / Q000706:statistics & numerical data*; D017115:Catheter Ablation / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D006325:Heart Atria / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D011183:Postoperative Complications / Q000453:epidemiology* / Q000517:prevention & control; D015995:Prevalence; D012307:Risk Factors; D025321:Surgery, Computer-Assisted / Q000379:methods / Q000706:statistics & numerical data*; D016896:Treatment Outcome
keywords: LA fibrosis; atrial fibrillation; catheter ablation; low-voltage area; meta-analysis