title: Myocardial injury during radiofrequency and cryoablation of typical atrial flutter.
abstract: OBJECTIVE
  Cardiac enzyme elevation after radiofrequency (RF) catheter ablation of atrial flutter (AFL) is common. Some studies found that cryoablation (CRYO) of AFL, compared to RF, is associated with higher levels of troponin, a finding that may indicate CRYO causes a greater amount of myocardial injury than RF. However, other investigations found no significant differences between troponin levels after CRYO versus RF. We have in a randomized study compared the post-procedural troponin I levels in RF and CRYO and the possible relation to procedural outcome and complications.
  
  
  METHODS
  We randomized 153 patients with cavotricuspid isthmus (CTI)-dependent AFL to CRYO or RF (78 CRYO; 75 RF). RF was performed with a 3.5-mm open-irrigated-tip catheter, and CRYO was performed with an 8-mm-tip catheter. Troponin I levels were measured before and 6 h after ablation.
  
  
  RESULTS
  Acute procedural success was achieved in 71/75 patients in the RF and in 72/78 patients in the CRYO. Troponin I levels were significantly elevated in both groups (baseline 0.012, 6th hour 0.35 ng/ml; p < 0.001). Troponin I levels were similar for RF and CRYO. Troponin I levels were higher in patients with acute failure compared to patients with acute success (0.48 ± 0.4 and 0.34 ± 0.16 ng/ml, p = 0.029); however, there was no difference between patients with or without late recurrence. There were no major complications in any group.
  
  
  CONCLUSIONS
  RF and CRYO for CTI-dependent AFL resulted in similar amounts of procedural myocardial injury. Troponin I levels had no prognostic value for late recurrence of AFL and there were no complications related to high troponin I levels.
authors.affiliation: All Department of Cardiology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden. serkankard@gmail.com.|Cardiology Department, Karolinska University Hospital, M52, 141 86, Huddinge, Stockholm, Sweden. serkankard@gmail.com.
authors.forename: Serkan
authors.initials: S
authors.lastname: Saygi
authors.affiliation: All Department of Cardiology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Nikola
authors.initials: N
authors.lastname: Drca
authors.affiliation: All Department of Cardiology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Insulander
authors.affiliation: All Department of Cardiology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Schwieler
authors.affiliation: All Department of Cardiology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Mats
authors.initials: M
authors.lastname: Jensen-Urstad
authors.affiliation: All Department of Cardiology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Hamid
authors.initials: H
authors.lastname: Bastani
mesh_terms: D000368:Aged; D001282:Atrial Flutter / Q000097:blood / Q000453:epidemiology* / Q000601:surgery*; D015415:Biomarkers / Q000097:blood; D017115:Catheter Ablation / Q000706:statistics & numerical data*; D003452:Cryosurgery / Q000706:statistics & numerical data*; D005260:Female; D006335:Heart Injuries / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D008297:Male; D011183:Postoperative Complications / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology; D011379:Prognosis; D012008:Recurrence; D018570:Risk Assessment; D016037:Single-Blind Method; D013548:Sweden / Q000453:epidemiology; D016896:Treatment Outcome; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D019210:Troponin I
keywords: Atrial flutter; Cryoablation; RF ablation; Troponin I