MEDAFI-Trial (Micro-embolization during ablation of atrial fibrillation): comparison of pulmonary vein isolation using cryoballoon technique vs. radiofrequency energy.
OBJECTIVE
Cerebral embolism is a possible serious complication during catheter ablation of atrial fibrillation (AF). The purpose of this prospective pilot study was to analyse the incidence and possible impact of cryo ablation on cerebral lesions and possible differences to radiofrequency (RF) ablation during pulmonary vein isolation (PVI).


RESULTS
Pulmonary vein isolation was performed in 89 patients, either with the cryoballoon technique (n = 45) or with RF ablation (n = 44). Phenprocoumon was stopped 3 days before intervention and replaced by subcutaneous low-molecular-weight heparin. During the catheter procedure, an infusion of unfractionated heparin was maintained to achieve an activated clotting time (ACT) of > 300 s. Cerebral magnetic resonance imaging scans were performed 1 day before and after PVI, and at 3-month follow-up. Chronic lesions were observed in 11 patients (12.3%) before PVI without statistically significant difference between the two groups. None of the patients had neurological symptoms during or following the procedure. Seven patients (7.9%) developed acute lesions 1 day after PVI, without statistically significant difference between the group treated by cryoenergy (8.9%) and RF ablation (6.8%). Patients with acute lesions were significantly older compared with those without acute cerebral lesions. No additional cerebral lesions during follow-up were observed.


CONCLUSIONS
A considerable portion of patients with AF but without any neurological symptoms had chronic cerebral lesions before PVI. Additional acute lesions could be added after the procedure. Both ablation techniques showed additional cerebral acute lesions with no neurological symptoms after PVI.
Neumann
Thomas
T
Department of Cardiology, Kerckhoff Heart Center, Benekestrasse 2-8, 61231 Bad Nauheim, Germany. t.neumann@kerckhoff-klinik.de
Kuniss
Malte
M
Conradi
Guido
G
Janin
Sebastien
S
Berkowitsch
Alexander
A
Wojcik
Maciej
M
Rixe
Johannes
J
Erkapic
Damir
D
Zaltsberg
Sergey
S
Rolf
Andreas
A
Bachmann
Georg
G
Dill
Thorsten
T
Hamm
Christian W
CW
Pitschner
Heinz-Friedrich
HF
D001281:Atrial Fibrillation / Q000453:epidemiology / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects* / Q000379:methods; D002544:Cerebral Infarction / Q000453:epidemiology; D015897:Comorbidity; D003452:Cryosurgery / Q000009:adverse effects* / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D020766:Intracranial Embolism / Q000175:diagnosis / Q000453:epidemiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D015995:Prevalence; D011446:Prospective Studies; D011667:Pulmonary Veins / Q000601:surgery*; D012307:Risk Factors