The study of atrial fibrillation (AF) has been known as a hot topic of clinical concern. Body surface potential mapping (BSPM), a noninvasive electrical mapping technology, has been widely used in the study of AF. This study adopted 10 AF patients' preoperative and postoperative BSPM data (each patient's data contained 128 channels), and applied the autocorrelation function method to obtain the activation interval of the BSPM signals. The activation interval results were compared with that of manual counting method and the applicability of the autocorrelation function method was verified. Furthermore, we compared the autocorrelation function method with the commonly used fast Fourier transform (FFT) method. It was found that the autocorrelation function method was more accurate. Finally, to find a simple rule to predict the recurrence of atrial fibrillation, the autocorrelation function method was used to analyze the preoperative BSPM signals of 10 patients with persistent AF. Consequently, we found that if the patient's proportion of channels with dominant frequency larger than 2.5 Hz in the anterior left region is greater than the other three regions (the anterior right region, the posterior left region, and the posterior right region), he or she might have a higher possibility of AF recurrence. This study verified the rationality of the autocorrelation function method for rhythm analysis and concluded a simple rule of AF recurrence prediction based on this method.

BACKGROUND:Peripheral nerves play an important role in bone metabolism.In clinical practice,the specific impact of nerve injury on bone transport technology needs further study. OBJECTIVE:To investigate the effect of tibial nerve injury on the treatment of tibial slip by single-plane osteotomy. METHODS:Thirty-two patients with tibial bone defects admitted to Tangshan Second Hospital from May 2011 to June 2022 were selected.According to the presence or absence of tibial nerve injury,patients were divided into the tibial nerve injury group(n=16)and the non-tibial nerve injury group(n=16).Both groups were treated with single-plane osteotomy and bone slip.After treatment,the patients were followed up to collect the mineralization zone healing index,external fixation index,docking point healing and needle infection.After the removal of external fixation,the bone healing and functional evaluation were evaluated by a classification of the Association for the Study and Application of the Method of Ilizarov(ASAMI). RESULTS AND CONCLUSION:(1)All 32 patients were followed up for(25.28±4.79)months.There were no significant differences in bone healing time,external fixation time,healing index and external fixation index between the two groups(P＞0.05).Needle infection occurred in two cases of the tibial nerve injury group and one case of the non-tibial nerve injury group,all of which were PALEY I,and there was no significant difference between the two groups(P＞0.05).The non-union rate of the occlusal end of the tibial nerve injury group was 31%,and that of the non-tibial nerve injury group was 13%;there was no statistical difference between the two groups(P＞0.05).The excellent and good rate of ASAMI bone healing score in the two groups was 100%;the excellent and good rate of limb score was 81%in the tibial nerve injury group and 94%in the non-tibial nerve injury group;there was no statistical difference between the two groups(P＞0.05).(2)Our research shows that tibial nerve injury has no significant effect on the mineralization speed,external fixation time,union of the occlusal end,infection of the needle tract,and the quality of bone formation in the mineralized area of the single-plane osteotomy.