A randomized double-blind study of epicardial left atrial cryoablation for permanent atrial fibrillation in patients undergoing mitral valve surgery: the SWEDish Multicentre Atrial Fibrillation study (SWEDMAF).
OBJECTIVE
The efficacy of epicardial left atrial (LA) cryoablation in eliminating atrial fibrillation (AF) in patients undergoing mitral valve surgery (MVS) is unknown. We hypothesized that MVS combined with LA cryoablation is superior to MVS alone.


RESULTS
Sixty-nine patients with permanent AF, included at four centres, underwent MVS with or without epicardial LA cryoablation. The primary endpoint was regained sinus rhythm. Risk factors for failed AF cryoablation were elucidated. Sixty-five out of 69 patients reached the primary endpoint. At 6 and 12 months follow-up, 73.3% of patients who underwent cryoablation had regained sinus rhythm at both follow-ups, compared with 45.7 and 42.9% of patients, respectively, who underwent MVS alone (group differences, at 6 months P = 0.024, after 12 months P = 0.013). The in-hospital complication rate was 11.4% in the MVS group and 26.5% in the cryoablation group (P = 0.110). Risk factors for failed elimination of AF by cryoablation were duration of permanent AF (P = 0.012) and presence of coronary artery disease (P = 0.047), according to multiple logistic regression analysis.


CONCLUSIONS
This first prospective randomized study showed that combining MVS with epicardial LA cryoablation is significantly better in eliminating pre-operative permanent AF than MVS alone.
Blomström-Lundqvist
Carina
C
Department of Cardiology, Uppsala University Hospital, SE-75185 Uppsala, Sweden. carina.blomstrom.lundqvist@akademiska.se
Johansson
Birgitta
B
Berglin
Eva
E
Nilsson
Leif
L
Jensen
Steen M
SM
Thelin
Stefan
S
Holmgren
Anders
A
Edvardsson
Nils
N
Källner
Göran
G
Blomström
Per
P
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000209:etiology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D003131:Combined Modality Therapy / Q000379:methods; D003452:Cryosurgery / Q000379:methods*; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000601:surgery*; D011446:Prospective Studies