Robotically assisted ablation produces more rapid and greater signal attenuation than manual ablation.
BACKGROUND
Robotic remote catheter ablation potentially provides improved catheter-tip stability, which should improve the efficiency of radiofrequency energy delivery. Percentage reduction in electrogram peak-to-peak voltage has been used as a measure of effectiveness of ablation. We tested the hypothesis that improved catheter-tip stability of robotic ablation can diminish signals to a greater degree than manual ablation.


METHODS
In vivo NavX maps of 7 pig atria were constructed. Separate lines of ablation were performed robotically and manually, recording pre- and postablation peak-to-peak voltages at 10, 20, 30, and 60 seconds and calculating signal amplitude reduction. Catheter ablation settings were constant (25W, 50 degrees , 17 mL/min, 20-30 g catheter tip pressure). The pigs were sacrificed and ablation lesions correlated with NavX maps.


RESULTS
Robotic ablation reduced signal amplitude to a greater degree than manual ablation (49 +/- 2.6% vs 29 +/- 4.5% signal reduction after 1 minute [P = 0.0002]). The mean energy delivered (223 +/- 184 J vs 231 +/- 190 J, P = 0.42), power (19 +/- 3.5 W vs 19 +/- 4 W, P = 0.84), and duration of ablation (15 +/- 9 seconds vs 15 +/- 9 seconds, P = 0.89) was the same for manual and robotic. The mean peak catheter-tip temperature was higher for robotic (45 +/- 5 degrees C vs 42 +/- 3 degrees C [P < 0.0001]). The incidence of >50% signal reduction was greater for robotic (37%) than manual (21%) ablation (P = 0.0001).


CONCLUSIONS
Robotically assisted ablation appears to be more effective than manual ablation at signal amplitude reduction, therefore may be expected to produce improved clinical outcomes.
Imperial College Healthcare NHS Trust; National Heart and Lung Institute, Imperial College London, St. Mary's Hospital, London, UK.
Michael
M
Koa-Wing
Pipin
P
Kojodjojo
Louisa C
LC
Malcolme-Lawes
Tushar V
TV
Salukhe
Nick W F
NW
Linton
Aaron P
AP
Grogan
Dale
D
Bergman
Phang Boon
PB
Lim
Zachary I
ZI
Whinnett
Karen
K
McCarthy
Siew Yen
SY
Ho
Mark D
MD
O'Neill
Nicholas S
NS
Peters
D Wyn
DW
Davies
Prapa
P
Kanagaratnam
D000200:Action Potentials; D000818:Animals; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery*; D012371:Robotics / Q000379:methods*; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013552:Swine