Relationship Between Atrial Muscle Injury Mediated By Inflammation And Metabolic Abnormalities And Atrial Fibrillation

Atrial fibrillation(AF)is a progressive disease that usually begins with short,episodic episodes that end on their own,then progresses to more frequent episodes that eventually lead to persistent and permanent AF that does not end on its own.AF disease progression is associated with increased cardiovascular comorbidities and mortality,AF disease progression reduces the effectiveness of drug therapy and rhythm control strategies The most common risk factors for AF progression are age,hypertension,obesity,heart failure,and diabetes,and hypercoagulability may be involved in increasing the risk of stroke and AF progression.Appropriate risk factor treatment can improve sinus rhythm maintenance,cardiovascular outcomes,and reverse atrial fibrillation progression.Therefore,intervention and control of risk factors related to atrial fibrillation or early and accurate detection of atrial fibrillation can enable doctors to formulate anticoagulation,ablation and other treatment plans as soon as possible,and improve patient prognosis has important practical significance.At present,several studies have confirmed that metabolic abnormalities and inflammatory responses are involved in the occurrence and maintenance of atrial fibrillation,and exploring their relationship to add detailed multimodal phenotypes may contribute to increasing the understanding of the progression of atrial fibrillation and contribute to personalized medicine.Part One Monocyte/High-Density Lipoprotein Ratio Is Associated with Atrial High-Rate Episodes within One Year Detected by Car-diac Implantable Electronic DevicesObjective: To investigate the risk factors for predicting atrial high-rate episodes(AHREs)detected by cardiac implantable electronic devices(CIEDs).Methods:1.A total of 140 patients with CIED in our hospital from June 2013 to June 2018 were included and were followed up to observe whether they had AHREs.AHREs are defined as atrial rate ≥ 175 times/minute,lasting > 5minutes,and reviewed by an experienced electrophysiologist with unclear clinical diagnosis.2.The patients fasted for 12 hours before implantation,and blood samples were collected for biochemical,lipid,and whole blood count detection.Follow-up was regular after discharge to record follow-up data of each patient and conduct statistical analysis.Results:1.One hundred and forty patients were implanted with dual-chamber pacemakers,their median age was 70 years old,44.29% were male,27 patients AHREs within one year,and AHREs incidence rate was 19.29%.2.The microcytic to hypochromic(M/H)ratio was calculated for all AHREs patients and compared with the patients without AHREs;the M/H value of AHREs patients was significantly higher.3.Throughout the entire follow-up period,a total of 44 patients deve--loped AHREs;when adjusted by multivariate analysis,only M/H ratio ≥ 4.5vs.< 4.5 had statistical significance,and the adjusted hazard ratio value was4.313(1.675-11.105).Conclusions: As an indicator,M/H ratio may play an important role in the occurrence and development of atrial fibrillation and can be used as a predictor of AHREs in patients with CIED.Part Two Effects of atrial fibrillation model construction on atrial remodeling,inflammation level and atrial muscle metabo-lism in dogsObjective: To establish a model of atrial fibrillation in Beagle dogs,and to explore the effects of inflammation and myocardial metabolism on atrial fibrosis and atrial remodeling during the occurrence and development of atrial fibrillation,so as to provide new ideas for the prevention,diagnosis and treatment of atrial fibrillation.Methods: 1.Twelve male beagle dogs were randomly divided into two groups by random number method: Sham group(6 dogs)and atrial fibrillation group(6 dogs).In the atrial fibrillation group,the atrial fibrillation model was prepared by the method of overspeed pacing of the left atrium with pacemaker.All dogs were fed under the same feeding conditions for 8 weeks.2.Venous blood was taken before pacing,at 2,4,6 and 8 weeks respectively to detect the levels of inflammatory factors.3.The left atrial structure was evaluated before pacing and at 4 and 8 weeks after pacing.4.After 8 weeks,molecular biology techniques and histology were used to investigate the effects of inflammation and myocardial metabolism on atrial fibrosis and atrial remodeling in the occurrence and development of atrial fibrillation in the two groups.Results: 1.Left atrial remodeling occurred in atrial fibrillation group,and compared with Sham group,left atrial diameter,upper and lower diameter,atrial fibrillation maintenance time and atrial fibrillation induction rate were significantly increased.2.Compared with Sham group,HE staining and Masson staining in AF group,and transmission electron microscopy observation results showed that the atrial myocardium structure in AF group was disordered,fiber tissue between myocardium bundles was hyperplasia,fiber strips were formed between tissues,muscle fibers were broken,mitochondrial arrangement was disordered,swelling,and ridge structure disappeared.3.The serum levels of C-reactive protein,tumor necrosis factor-α,IL-1β and IL-6 were detected by enzyme-linked immunoassay(ELISA)before pacing and at 2,4,6 and 8 weeks after pacing.The results showed that the levels of inflammatory factors in atrial fibrillation group were increased compared with those before pacing.4.After 8 weeks,the expression levels of C-reactive protein,tumor necrosis factor-α,IL-1β and IL-6 in atrial tissue were up-regulated,and NF-κB-related proteins in atrial tissue inflammation signaling pathway were increased in atrial fibrillation group.5.In the atrial fibrillation group,the expression of anaerobic glycolytic related protein was increased,and the content of blood lactic acid in the left atrial tissue and coronary sinus was increased.Protein lactating panantibody was used to detect total protein,and the levels of multiple band protein lactating modification increased in atrial fibrillation group.Conclusion: Central atrial fibrosis and atrial remodeling are aggravated during canine atrial fibrillation.Inflammation and atrial muscle metabolism are involved in the occurrence and maintenance of atrial fibrillation.