Gold vs. platinum-iridium tip catheter for cavotricuspid isthmus ablation: the AURUM 8 study.
OBJECTIVE
Gold electrodes have the theoretical advantage of creating bigger lesions than platinum-iridium (Pt-Ir) electrodes. We performed a prospective randomized study to compare the clinical efficacy of standard 8 mm Pt-Ir tip catheter (control) and 8 mm gold-tip catheters in the ablation of the cavotricuspid isthmus (CTI)-dependent atrial flutter.


RESULTS
A total of 463 patients undergoing CTI ablation in 19 clinical centres were randomized to receive the treatment by gold-tip or control catheter. The primary endpoint was cumulative radiofrequency (RF) application duration until achieving bidirectional CTI block. It did not differ significantly for the two catheters. The gold-tip catheter was, however, associated with a higher ablation success rate (94.3 vs. 89.0%, P = 0.042) and a substantially lower incidence of char and coagulum formation (4.8 vs. 37.9%, P < 0.001), which required exchange of 1 gold-tip (0.4%) and 10 control catheters (4.6%, P = 0.005). The gold-tip catheter delivered more mean power (52 ± 12 W) than the control catheter (48 ± 13 W, P < 0.001). Both mean and maximum temperatures measured by the thermocouple integrated in the catheter tip were statistically significantly lower in the gold (mean: 53.2 ± 4.7°C, max: 68.7 ± 6.6°C) than in the control catheter (54.3 ± 5.2 and 70.2 ± 7.0°C, respectively, P < 0.05). Fluoroscopy time, procedure duration, procedural-related complications, and arrhythmia recurrence during 6 months of follow-up did not differ between the two catheters.


CONCLUSIONS
Owing to a higher primary ablation success rate and reduced incidence of char/coagulum formation, gold may be preferred over Pt-Ir as electrode material for 8 mm tip catheters for CTI ablation. ClinicalTrials.gov: NCT00326001 (http://clinicaltrials.gov/ct2/show/NCT00326001).
Lewalter
Thorsten
T
Department of Internal Medicine, Vascular and Arrhythmia Center Rhineland-Bonn, St. Marienhospital Bonn, Academic Hospital, University of Bonn, Robert-Koch-Str. 1, 53115 Bonn, Germany. th.lewalter@uni-bonn.de
Weiss
Christian
C
Spencker
Sebastian
S
Jung
Werner
W
Haverkamp
Wilhelm
W
Willems
Stephan
S
Deneke
Thomas
T
Kautzner
Josef
J
Wiedemann
Michael
M
Siebels
Jürgen
J
Pitschner
Heinz Friedrich
HF
Hoffmann
Ellen
E
Hindricks
Gerd
G
Zabel
Markus
M
Vester
Ernst
E
Schwacke
Harald
H
Mittmann-Braun
Erica
E
Lickfett
Lars
L
Hoffmeister
Sabine
S
Proff
Jochen
J
Mewis
Christian
C
Bauer
Wolfgang
W
D000368:Aged; D001282:Atrial Flutter / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D005260:Female; D005500:Follow-Up Studies; D006046:Gold; D006801:Humans; D007495:Iridium; D008297:Male; D008875:Middle Aged; D010984:Platinum; D011446:Prospective Studies; D012008:Recurrence; D012189:Retrospective Studies; D013814:Thermal Conductivity; D016896:Treatment Outcome
C077763:platinum-iridium alloy; D007495:Iridium; D010984:Platinum; D006046:Gold