title: Relationship between cycle length of typical atrial flutter and double potential interval after achievement of complete isthmus block.
abstract: BACKGROUND
  There is some disagreement concerning the minimal value of the interval between components of double potentials (DPs interval) that allows distinguishing complete and incomplete block in the cavotricuspid isthmus (CTI).
  
  
  OBJECTIVE
  To assess clinical utility of the relationship between atrial flutter cycle length (AFL CL) and the DPs interval.
  
  
  METHODS
  Ablation of the CTI was performed in 87 patients during AFL (245 ± 40 ms). Subsequently, DPs were recorded during proximal coronary sinus pacing at sites close to a gap in the ablation line and after achievement of complete isthmus block.
  
  
  RESULTS
  We noted strong correlation between AFL CL and the DPs interval after achievement of isthmus block (r = 0.73). The mean DPs interval was 95.3 ± 18.3 ms (range 60-136 ms) and 123.3 ± 24.3 ms (range 87-211 ms) during incomplete and complete isthmus block, respectively (P < 0.001). When expressed as a percentage of AFL CL, this interval was 35.7 ± 3.5% AFL CL (range 28-40.2%) and 50.4 ± 6.9% AFL CL (range 39-72%) during incomplete and complete isthmus block, respectively (P < 0.001). A cutoff value of 40% of AFL CL identified CTI block with 96.7% sensitivity and 100% specificity.
  
  
  CONCLUSIONS
  The interval between DPs after achievement of block in the CTI correlates with AFL CL. The DPs interval expressed as a percentage of AFL CL allows better distinguishing between complete and incomplete isthmus block compared to standard method based on milliseconds. The DPs interval below 40% of AFL CL indicates sites close to a gap in the ablation line.
authors.affiliation: Institute of Cardiology, Warsaw, Poland. pderejko@yahoo.com
authors.forename: Paweł
authors.initials: P
authors.lastname: Derejko
authors.forename: Robert
authors.initials: R
authors.lastname: Bodalski
authors.forename: Łukasz J
authors.initials: ŁJ
authors.lastname: Szumowski
authors.forename: Dariusz
authors.initials: D
authors.lastname: Kozłowski
authors.forename: Piotr
authors.initials: P
authors.lastname: Urbanek
authors.forename: Michał
authors.initials: M
authors.lastname: Orczykowski
authors.forename: Joanna
authors.initials: J
authors.lastname: Zakrzewska-Koperska
authors.forename: Roman
authors.initials: R
authors.lastname: Kepski
authors.forename: Lidia
authors.initials: L
authors.lastname: Chojnowska
authors.forename: Magdalena
authors.initials: M
authors.lastname: Polańska
authors.forename: Ewa
authors.initials: E
authors.lastname: Szufladowicz
authors.forename: Anna
authors.initials: A
authors.lastname: Wójcik
authors.forename: Frédéric
authors.initials: F
authors.lastname: Sacher
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
authors.forename: Franciszek
authors.initials: F
authors.lastname: Walczak
mesh_terms: D000328:Adult; D000368:Aged; D001282:Atrial Flutter / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D054326:Coronary Sinus / Q000503:physiopathology / Q000601:surgery; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods; D005260:Female; D006327:Heart Block / Q000503:physiopathology / Q000601:surgery; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome; D014261:Tricuspid Valve / Q000503:physiopathology / Q000601:surgery