title: The benefit of tissue contact monitoring with an electrical coupling index during ablation of typical atrial flutter--a prospective randomised control trial.
abstract: BACKGROUND
  We sought to investigate the use of tissue contact monitoring by means of the electrical coupling index (ECI) in a prospective randomised control trial of patients undergoing cavotricuspid isthmus (CTI) ablation for atrial flutter.
  
  
  METHODS
  Patients with ECG-documented typical flutter undergoing their first CTI ablation were randomised to ECI™-guided or non-ECI™-guided ablation. An irrigated-tip ablation catheter was used in all cases. Consecutive 50-W, 60-s radiofrequency lesions were applied to the CTI, from the tricuspid valve to inferior vena cava, with no catheter movement permitted during radiofrequency (RF) delivery. The ablation endpoint was durable CTI block at 20 min post-ablation. Patients underwent routine clinic follow-up post-operatively.
  
  
  RESULTS
  A total of 101 patients (79 male), mean age 66 (+/-11), 50 ECI-guided and 51 control cases were enrolled in the study. CTI block was achieved in all. There were no acute complications. All patients were alive at follow-up. CTI block was achieved in a single pass in 36 ECI-guided and 30 control cases (p = 0.16), and at 20 min post-ablation, re-conduction was seen in 5 and 12 cases, respectively (p = 0.07). There was no significant difference in total procedure time (62.7 ± 33 vs. 62.3 ± 33 min, p = 0.92), RF requirement (580 ± 312 vs. 574 ± 287 s, p = 0.11) or fluoroscopy time (718 ± 577 vs. 721 ± 583 s, p = 0.78). After 6 ± 4 months, recurrence of flutter had occurred in 1 (2 %) ECI vs. 8 (16 %) control cases (OR 0.13, 95 % CI 0.01-1.08, p = 0.06).
  
  
  CONCLUSIONS
  ECI-guided CTI ablation demonstrated a non-statistically significant reduction in late recurrence of atrial flutter, at no cost to procedural time, radiation exposure or RF requirement.
authors.affiliation: Department of Cardiology, Oxford University Hospitals NHS Trust, Oxford, OX3 9DU, United Kingdom, michael.jones@ouh.nhs.uk.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Jones
authors.forename: David
authors.initials: D
authors.lastname: Webster
authors.forename: Kelvin C K
authors.initials: KC
authors.lastname: Wong
authors.forename: Christopher
authors.initials: C
authors.lastname: Hayes
authors.forename: Norman
authors.initials: N
authors.lastname: Qureshi
authors.forename: Kim
authors.initials: K
authors.lastname: Rajappan
authors.forename: Yaver
authors.initials: Y
authors.lastname: Bashir
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Betts
mesh_terms: D000368:Aged; D001282:Atrial Flutter / Q000175:diagnosis* / Q000601:surgery*; D018780:Body Surface Potential Mapping / Q000379:methods*; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D016343:Monitoring, Intraoperative / Q000379:methods*; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome