Prediction of improvement in left atrial function index after catheter ablation for atrial fibrillation.
OBJECTIVE
Although left atrial function index is reportedly a possible predictor of hospitalization for heart failure and of stroke irrespective of the presence or not of atrial fibrillation (AF), the effects of catheter ablation on left atrial function index have not yet been reported.


METHODS
We performed catheter ablation on 55 patients (age 56.6 ± 9.6 years; 44 men; 30 with paroxysmal and 25 with persistent, long-standing AF) and evaluated them by transthoracic echocardiography preoperatively and 3 monthly for 12-24 months after catheter ablation. We then compared clinical characteristics and echocardiographic variables before catheter ablation between two groups: the 42 subjects with the most recent left atrial function index <30 and the 13 in which it was ≥30.


RESULTS
Left atrial function index improved after catheter ablation in both groups, plateauing 6 months after the procedure. Univariate analysis showed statistically significant differences in the prevalence of chronic AF and left atrial emptying fraction, diameter, and maximum and minimum volume (prevalence of chronic AF, p < 0.05; others, p < 0.01) between the groups. Multivariate analysis showed that only maximum left atrial volume predicts left atrial function index after catheter ablation (p < 0.05). In addition, we used ROC analysis to calculate a cutoff value for LA maximum volume as a good predictor and found that a good cutoff value was 63.5 mL, the sensitivity and specificity being 0.75 and 0.75, respectively.


CONCLUSIONS
Catheter ablation improves left atrial function index. However, in patients with left atrial maximum volume of over 63.5 mL on echocardiography, the index did not recover to within the normal range after catheter ablation.
Department of Cardiology, International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan.
Takahiko
T
Nagase
Department of Cardiology, International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan. ritsn@saitama-med.ac.jp.
Ritsushi
R
Kato
Department of Cardiology, International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan.
Shintaro
S
Nakano
Department of Cardiology, International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan.
Yuichirou
Y
Shiki
Department of Cardiology, International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan.
Sayaka
S
Tanaka
Department of Cardiology, International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan.
Yoshifumi
Y
Ikeda
Department of Cardiology, International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan.
Shiro
S
Iwanaga
Department of Cardiology, International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan.
Shigeyuki
S
Nishimura
Department of Cardiology, International Medical Center, Saitama Medical University, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan.
Kazuo
K
Matsumoto
D001281:Atrial Fibrillation / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D016279:Atrial Function, Left; D017115:Catheter Ablation; D005260:Female; D006334:Heart Function Tests / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D020127:Recovery of Function; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D014463:Ultrasonography
Atrial fibrillation; Catheter ablation; Echocardiography; Left atrial function index; Predictor