Outcome Predictors for Surgical Atrial Fibrillation Ablation Concomitant to Mitral Valve Surgery

Objectives: Concomitant surgical ablation is an established procedure, recommended in guidelines for patients with atrial fibrillation (AF) undergoing cardiac surgery. AF is very common among patients with mitral valve disease. We therefore analyzed predictors of rhythm outcome in a large patient collective receiving mitral valve surgery and concomitant ablation.

Methods: Between 2003 and 2016, 419 patients with persistent (n = 266, 63.5%) or paroxysmal (n = 153, 36.5%) AF underwent surgical AF ablation concomitant to mitral valve surgery. Two hundred and nine (49.8%) patients received isolated MVR, while 210 (50.1%) patients received combined mitral valve procedures. The lesions were either limited to a pulmonary vein isolation (n = 39, 9.3%), a complete left atrial lesion set 256 (61.1%), or biatrial lesions (n = 124, 29.6%). Follow-up rhythm evaluations were based on either 24-hour Holter ECG or event recorder interrogation at 3, 6, and 12 months postoperatively.

Results: Mean patients age was 66.1 ± 14.6 years, 238 (56.8%) were male. There were no major ablation-related complications. Survival rate after 1-year follow-up was 93%. After 1-year follow-up, freedom from AF was 65.2%, showing significantly better results in patients with paroxysmal AF compared with those with persistent AF (75.6 vs. 58.3%, p = 0.0014). Logistic regression analysis confirmed smaller left atrial diameter (p = 0.023) and paroxysmal AF (p = 0.0011) as statistically significant predictors for freedom from AF. Neither energy source nor additional surgical procedure significantly influenced rhythm results. Regarding only patients with persistent AF, those receiving a biatrial lesion set showed a trend toward higher rates of freedom from AF, but without statistically significant differences (biatrial 66.9% vs. left atrial 55.3%, p = 0.067).

Conclusion: Surgical AF ablation, concomitant to mitral valve surgery is a safe and effective procedure. Statistically significant predictors for freedom from AF after 12 months were preoperative paroxysmal AF and smaller left atrial diameter.

No conflict of interest has been declared by the author(s).