Focal impulse and rotor modulation using the novel 64-electrode basket catheter: electrogram characteristics of human rotors.
OBJECTIVE
Ablation of fractionated electrograms (EGMs) has been performed to eliminate areas of slow conduction in atrial fibrillation (AF). The rotor hypothesis suggests that rapidly activating spiral waves perpetuate and maintain AF. This study describes the EGM characteristics of AF rotors, using the novel 64-electrode basket catheter.


RESULTS
Twenty-five patients (male n = 16) with AF (paroxysmal n = 10) underwent focal impulse and rotor modulation. A 3.5 mm irrigated-tip ablation catheter was placed at the identified rotor core and EGMs were analysed for amplitude, characteristics (single-EGM, fractionated-EGM, and continuous-EGM), and cycle length over 10 s. A total of 72 rotors were identified [right atrium (RA) = 13, left atrium (LA) = 59]. Seven rotors were excluded from EGM analysis due to location in the pulmonary veins. Single-EGMs were more frequent in the RA compared with the LA (8 (61.5) vs. 12 (23.1); P < 0.01) and EGM amplitudes were smaller in LA rotors when compared with RA rotors (0.14 (0.08-0.17) mV vs. 0.19 (0.15-0.29) mV; P = 0.029). In patients with persistent AF, single-EGMs were observed more often in the right-sided rotors compared with left-sided rotors (4 (57.1) vs. 5 (14.3); P = 0.012), and EGM amplitudes were smaller in patients with persistent AF compared with paroxysmal atrial fibrillation (PAF) patients (0.15 (0.09-0.19) mV vs. 0.22 (0.17-0.47) mV; P = 0.03). Furthermore, the prevalence of fractionated- EGMs was higher in patients with persistent AF compared with PAF patients (31/42 (73.8) vs. 9/23 (39.1); P = 0.03).


CONCLUSIONS
There are no characteristic rotor-EGM potentials. Rotor-EGM characteristics are different between the RA and LA. Although rotors are not associated with abnormal EGMs, rotor-EGMs in persistent AF were more fractionated with lower amplitudes compared with that in PAF.
Department of Cardiology, Asklepios Klinik St. Georg, Lohmuehlenstrasse 5, Hamburg 20099, Germany tina9989@hotmail.com.
Tina
T
Lin
Department of Cardiology, Asklepios Klinik St. Georg, Lohmuehlenstrasse 5, Hamburg 20099, Germany.
Andreas
A
Rillig
Department of Cardiology, Asklepios Klinik St. Georg, Lohmuehlenstrasse 5, Hamburg 20099, Germany.
Tudor
T
Bucur
Department of Cardiology, Asklepios Klinik St. Georg, Lohmuehlenstrasse 5, Hamburg 20099, Germany.
Andreas
A
Metzner
Department of Cardiology, Asklepios Klinik St. Georg, Lohmuehlenstrasse 5, Hamburg 20099, Germany.
Shibu
S
Mathew
Department of Cardiology, Asklepios Klinik St. Georg, Lohmuehlenstrasse 5, Hamburg 20099, Germany.
Erik
E
Wissner
Asklepios Proresearch, Hamburg, Germany.
Peter
P
Wohlmuth
Department of Cardiology, Asklepios Klinik St. Georg, Lohmuehlenstrasse 5, Hamburg 20099, Germany.
Karl-Heinz
KH
Kuck
Department of Cardiology, Asklepios Klinik St. Georg, Lohmuehlenstrasse 5, Hamburg 20099, Germany.
Feifan
F
Ouyang
Department of Cardiology, Asklepios Klinik St. Georg, Lohmuehlenstrasse 5, Hamburg 20099, Germany.
Roland Richard
RR
Tilz
D000200:Action Potentials; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D016279:Atrial Function, Left; D016280:Atrial Function, Right; D062906:Cardiac Catheters; D017115:Catheter Ablation / Q000295:instrumentation*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D004867:Equipment Design; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D007507:Therapeutic Irrigation / Q000295:instrumentation; D016896:Treatment Outcome
Atrial fibrillation; EGM characteristics; FIRM mapping; Novel technologies; Rotors