{'fraction_non_alphanumeric': 0.02857142857142857, 'fraction_numerical': 0.023323615160349854, 'mean_word_length': 4.682119205298013, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Surgical ablation for atrial fibrillation using the Ex-Maze III procedure on the beating heart in patients undergoing mitral valve surgery.

BACKGROUND
The Ex-Maze III procedure is a recently developed surgical method for ablation of atrial fibrillation (AF). The procedure uses epicardial approach and can be performed on the beating heart.


AIM
To evaluate the efficacy and safety of Ex-Maze III ablation in patients undergoing mitral valve (MV) surgery.


METHODS
The study group consisted of 20 consecutive patients (8 males, mean age 67 years) who underwent MV surgery and had concomitant AF. Eighteen patients were diagnosed with long-standing permanent AF and 2 patients with paroxysmal AF. The mean duration of AF was 9.5 years prior to surgery. All the patients underwent the Ex-Maze III procedure on the beating heart immediately before the MV surgery (MV replacement in 17 patients and MV repair in 3 patients). The patients were followed 1, 3, 6 and 12 months after procedure with ECG and 24-h ambulatory ECG monitoring (at 12 months).


RESULTS
There were no serious complications in the study group. All the patients were in AF immediately after the procedure and underwent electrical or pharmacological cardioversion (4 and 16 patients, respectively). The proportion of patients remaining in sinus rhythm was 15 (75%) patients at 1 month, 16 (80%) patients at 3 months, 17 (85%) patients at 6 months and 12 months after procedure.


CONCLUSIONS
The Ex-Maze III procedure for ablation of AF on the beating heart is safe and effective in patients with AF undergoing concomitant MV surgery. In order to better evaluate the outcomes of the procedure a prospective randomised multicentre study is needed.