The effect of different ablation lines in left atrium on modified cardiac Cox maze procedure / 中华胸心血管外科杂志

ABSTRACT

Objective Background and objective The Cox maze Ⅲ procedure has been considered the gold standard for the surgical treatment of atrial fibrillation (AF) and the modified Cox maze use bipolar radiofrequency ablation instead of the cut-and-sew technique,while also reducing the connecting lines in left atrium.This study was to understand whether completely isolation the posterior left atrium by increasing left atrium ablation lines can enhance the survival after modified Cox maze procedure.Methods From Jan 2009 to Dec 2009,all the patients underwent the Cox maze procedure,following the same examination,were divided into two groups (case-control) box lesion group (n =60),which is means the right and lefi pulmonary vein lesions were connected inferiorly by adding ablation lines,thereby completely isolating the posterior left atrium and the non-box lesion group (n =60).Similar interventions were given during the perioperative periods.Comparing the risk factors before surgeries,then follow-up was 100％ complete,and the mean follow-up was 9 ± 8.4 months.Results Except the box lesion had long time of extracorporeal circulation,the characteristics of the 2 groups were similar because there were no differences in age,AF duration,left atrial diameter,left ventricular ejection fraction or homochronous operation between the groups and there was no operative death.No patient was lost to follow-up.In the mean follow-up duration,a patient was died of intracerebral hemorrhage at 2 months postoperationly in the box lesion group and a patient suffered from stroke at 12 months postoperationly in the non-box lesion.The overall freedom from AF recurrence was higher in the box lesion group at 1 (70％ vs 51.2％,P =0.039) and 3 (78.3％ vs 60％,P =0.030) months.While it was 80％ vs 71.7％ (P =0.286) at 6 months.Eight patients wrere readmitted because of the recurrence of AF,4 and 2 patients underwent catheter ablation in box and non-box group respectively,one patient in each group underwent electrical conversion.After treatment,all of the patients were recovered to sinus rhythm and continued to take cordarone.Conclusion Compared to the single connecting between right and left pulmonary vein,isolating the entire posterior left atrium by creating a box lesion showed higher freedom from AF in the earlier months (1-3months).However,half a year after the surgery,there were no significant differences between the two groups.