Endocardial radiofrequency ablation during mitral valve surgery: effect on cardiac rhythm, atrial size, and function.
BACKGROUND
Restoration of sinus rhythm is thought to lead to a reduction in left atrial size and to recovery of atrial contraction. We aimed to investigate changes in atrial size and function in patients undergoing radiofrequency ablation for atrial fibrillation during mitral valve surgery.


METHODS
In a prospective study, 70 patients (64 +/- 10 years) with mitral valve disease and atrial fibrillation underwent mitral surgery and left atrial endocardial radiofrequency ablation. Evaluation was achieved before surgery, at 7 days, 5 months, and 22 months after surgery. Maximal right and left atrial areas, left atrial diameter, and volume were measured. Atrial filling fraction (ventricular filling related to atrial contraction to total ventricular filling ratio) was used as an index of atrial contraction.


RESULTS
At the end of follow-up (22 +/- 10 months) most patients (91%) were in sinus rhythm. Actuarial freedom from atrial fibrillation recurrence was 62.5% after 2 years. Atrial size decreased, with a significant improvement in right (36 +/- 15 vs 10 +/- 20% preoperatively, p < 0.0001) and left (25 +/- 12 vs 7 +/- 14%, p < 0.0001) atrial filling fraction. Despite similar preoperative atrial size, at the end of follow-up atrial fibrillation recurrence was associated with a higher left atrial volume than in patients free of recurrence (41 +/- 14 vs 32 +/- 9 mL/m2, p = 0.004). Independent predictors of atrial fibrillation recurrence were previous mitral procedure (p = 0.029), left ventricular ejection fraction (p = 0.033), and mitral rheumatic lesion (p = 0.034).


CONCLUSIONS
Left atrial radiofrequency ablation for atrial fibrillation during mitral surgery is an effective procedure restoring sinus rhythm. Right and left atrial size was significantly reduced, with a recovery in atrial contraction.
Fayad
Georges
G
Service de Chirurgie Cardiovasculaire, Hôpital Cardiologique, CHRU de Lille, Lille, France. g-fayad@chru-lille.fr
Le Tourneau
Thierry
T
Modine
Thomas
T
Azzaoui
Richard
R
Ennezat
Pierre-Vladimir
PV
Decoene
Christophe
C
Deklunder
Ghislaine
G
Warembourg
Henri
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000150:complications* / Q000601:surgery; D017115:Catheter Ablation; D004452:Echocardiography; D015150:Echocardiography, Doppler; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000033:anatomy & histology*; D006334:Heart Function Tests; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D008945:Mitral Valve Prolapse / Q000601:surgery*; D008946:Mitral Valve Stenosis / Q000601:surgery*; D011446:Prospective Studies