Introduction. The left atrium posterior wall isolation (LAPW) is an important part of many modern strategies for the surgical treatment of non-paroxysmal atrial fibrillation (AF). The aim – to assess the capabilities of modern technologies of endocardial catheter ablation, thoracoscopic epicardial ablation (TTM) and open surgery of AF in achieving permanent isolation of the LAPW. Material and methods. We analyzed the data of re-ablations of patients with non-paroxysmal AF who had previously undergone the isolation of LAPW by various approaches: 43 patients after catheter procedure, 60 after totally thoracoscopic Maze procedure (Dallas lesion set, AtriCure Inc.) and 27 patients after open Maze surgery (cut & sew). The indications for the repeated endocardial stage were various atrial arrhythmias. In addition to mapping and eliminating the main cause of recurrence (atrial tachycardia, atrial flutter, or AF), the aim of the study was to control LAPW isolation, LAPW re-isolation (if conduction is restored), and to analyze the typical weak points of the previously applied technique. Results. The study showed that the achievement of permanent isolation of LAPW using isolated catheter ablation, and even epicardial thoracoscopic interventions, is not an easy task, and conduction restoration is a frequent finding during repeated procedures. A typical weak point common to catheter and thoracoscopic techniques is the roof line. Also, in the initial attempt to isolate the LSLP thoracoscopically, the conduction recovery zone is often located along the inferior line near the right inferior pulmonary vein (RIPV), which is associated with poor contact in this area. Almost all patients (except for one after TTM) managed to achieve re-isolation of LAPW on repeated catheter procedures. All patients after the open Maze (cut & sew) had an initially completely isolated PV-LAPW site, and the cause of arrhythmia recurrence was localized outside this area. Repeated radiofrequency catheter ablation (RFCA) (12 patients) after catheter LAPW re-isolation demonstrated permanent isolation in all cases. Arrhythmias are not covered by the design of previous abla- tions – ectopic/micro-reentry atrial tachycardias, various arrhythmias from the right atrium, or AF in combination with extensive fibrosis of both atria – were the causes of recurrence in the re-RFCA group. Conclusion. Repeated catheter ablation aimed at isolating the LAPW, as well as catheter ablation after the totally thoracoscopic Maze procedure (hybrid approach) – allow to achieve permanent LAPW isolation. A typical weak point of the thoracoscopic approach is the roof line in its various segments, as well as the lower line near the RIPV. These areas require special attention both during the initial procedure and during repeated endocardial RFCA. Based on the analysis of repeated RFCA, the only technique that guarantees the isola- tion of LAPW from one procedure is the Maze procedure in cut&sew modification. Isolation of the LAPW is an important component in the management of patients with non-paroxysmal AF, but does not exclude the possibility of recurrence of atrial arrhythmias, which are unique to the individual patient and not covered by the design of the PV-LAPW approach.