In vitro comparison of platinum-iridium and gold tip electrodes: lesion depth in 4 mm, 8 mm, and irrigated-tip radiofrequency ablation catheters.
OBJECTIVE
We compared a newly developed irrigated gold tip electrode ablation catheter and a gold tip 4 and 8 mm catheter with the corresponding platinum-iridium (Pt) tip catheters in an in vitro setting.


RESULTS
In a flow chamber simulating physiological flow conditions, radiofrequency catheter ablation was performed on tissue samples of porcine endomyocardium and liver. Lesion depth, energy and temperature delivery, and popping frequency were determined. Two hundred and fifty-three ablations were conducted. Four and eight millimetre, gold tip electrode catheters produced significantly deeper lesions compared with the Pt tip electrode (liver 4 mm: 4.67 +/- 1.7 vs. 2.9 +/- 1.0 mm, P < 0.0001; endomyocardium 4 mm: 3.88 +/- 1.1 vs. 2.81 +/- 0.7 mm, P < 0.001; liver 8 mm: 3.98 +/- 1.0 vs. 2.03 +/- 1.1 mm, P < 0.001; endomyocardium 8 mm: 4.00 +/- 0.9 vs. 3.39 +/- 0.8 mm, P < 0.001) and correlated with the amount of energy delivery. Popping frequency was significantly higher in gold tip electrodes. In irrigated tip electrodes, there was no difference in the lesion depth comparing gold with Pt (liver: 5.18 +/- 0.7 vs. 5.01 +/- 0.7 mm, P = ns; endomyocardium: 4.89 +/- 0.7 vs. 4.78 +/- 0.8 mm, P = ns). There was a trend towards less popping in the gold tip electrode.


CONCLUSIONS
Both 4 and 8 mm not-irrigated gold tip catheters produced deeper lesions than the corresponding Pt tip catheter. In irrigated tip catheters, gold and Pt tip material did not show differences in the lesion depth.
Linhart
Markus
M
Department of Medicine-Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany. markus.linhart@ukb.uni-bonn.de
Mollnau
Hanke
H
Bitzen
Alexander
A
Wurtz
Sabine
S
Schrickel
Jan W
JW
Andrié
René
R
Stöckigt
Florian
F
Weiss
Christian
C
Nickenig
Georg
G
Lickfett
Lars M
LM
Lewalter
Thorsten
T
D000818:Animals; D006348:Cardiac Surgical Procedures / Q000295:instrumentation / Q000379:methods; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D006046:Gold; D066298:In Vitro Techniques; D007495:Iridium; D008099:Liver / Q000601:surgery; D023421:Models, Animal; D010984:Platinum; D013552:Swine
D007495:Iridium; D010984:Platinum; D006046:Gold