title: Usefulness of non-contact mapping for radiofrequency catheter ablation of inappropriate sinus tachycardia: new procedural strategy and long-term clinical outcome.
abstract: OBJECTIVE
  The present study evaluated the clinical benefits of a new therapeutic method of radiofrequency catheter ablation (RFCA) using an EnSite system for inappropriate sinus tachycardia (IST).
  
  
  METHODS
  Six patients with debilitating IST underwent RFCA using EnSite. Using the beta-adrenergic blocker and agonist, the heart rate was controlled between 70 to 150 bpm before and after the RFCA. The areas of the breakout sites (BOSs) were clearly distinguished between those from the normal P-wave zones during rates of less than 100 bpm and those from more upper rate sites during rates of more than 100 bpm using the EnSite system, in accordance with the appearance of tall P-waves (tall P-wave zone) in the IST patients. This was selected as the target for ablation.
  
  
  RESULTS
  After the RFCA, the BOSs observed during heart rates of more than 100 bpm moved completely from the tall P-wave zone to the normal P-wave zone in the IST patients. The total number of heart beats and average heart beat on the 24-h Holter monitoring decreased statistically from that before the RFCA to that after, and no adverse heart rate responses was observed after the RFCA. Before the RFCA, the brain natriuretic peptide was elevated, New York Heart Association functional class was worse, and there was an impaired exercise tolerance observed with exercise electrocardiogram testing. The RFCA for the IST significantly improved those parameters.
  
  
  CONCLUSIONS
  This new therapeutic method for IST using EnSite is effective and produces clinical benefits.
authors.affiliation: Department of Cardiovascular Medicine, Kyushu University Hospital, Japan. matakemo@cardiol.med.kyushu-u.ac.jp
authors.forename: Masao
authors.initials: M
authors.lastname: Takemoto
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Mukai
authors.forename: Shujiro
authors.initials: S
authors.lastname: Inoue
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Matoba
authors.forename: Mari
authors.initials: M
authors.lastname: Nishizaka
authors.forename: Tomomi
authors.initials: T
authors.lastname: Ide
authors.forename: Akiko
authors.initials: A
authors.lastname: Chishaki
authors.forename: Kenji
authors.initials: K
authors.lastname: Sunagawa
mesh_terms: D000328:Adult; D018780:Body Surface Potential Mapping / Q000379:methods*; D017115:Catheter Ablation / Q000379:methods*; D015716:Electrocardiography, Ambulatory; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D013616:Tachycardia, Sinus / Q000175:diagnosis / Q000601:surgery*; D016896:Treatment Outcome