Surgical treatment of atrial fibrillation; a systematic review☆

In this review the efficacies of the alternative sources of energy (radiofrequency-microwave and cryo ablation; group I) and the classical 'cut and sew' Cox-Maze III (group II), which claims a 97-99% sinus rhythm (SR) success rate, were evaluated in the surgical treatment of atrial fibrillation (AF). A computerized search in the PubMed and Medline database was conducted. Only original, English written, clinical manuscripts on the surgical treatment of atrial fibrillation using an alternative source of energy or the classical 'cut and sew' Cox-Maze III technique, citing the clinical outcome, including the postoperative sinus rhythm, were included. The data included in this review were the number and percentage of treated patients, gender distribution, the type of arrhythmia and surgery, postoperative morbidity, pacemaker implantation rate, 30-day mortality, survival- and sinus rhythm conversion rates. Mean values for age, left atrial diameter, preoperative duration of AF and left ventricular ejection fraction were also recorded. Forty-eight studies were included comprising 3832 patients; 2279 in group I and 1553 in group II. The mean duration of AF, left atrial diameter and LVEF were 5.4 vs. 5.5 years (p=0.90), 55.5 vs. 57.8 mm (p=0.23) and 57 vs. 58% (p=0.63). The postoperative SR rates for group I and II were 78.3 vs. 84.9% (p=0.03). However, the "cut and sew" Cox-Maze III was conducted in younger patients (55.0 vs. 61.2 years; p=0.005), more often to treat paroxysmal (22.9 vs. 8.0%; p=0.05) and lone AF (19.3 vs. 1.6%). Alternative sources of energy were predominantly used to treat permanent AF (92.0%), almost always as a concomitant surgical procedure (98.4%) and increasingly in combination with non-mitral valve surgery (18.5%). After correction for these variations, the postoperative SR conversion rates for group I and II did not differ significantly anymore (p=0.260).