Stepwise Strategy for Treatment of Atrialfibrillation Substrate Study

Overview

Electrical/pharmacological cardioversion improves structural remodeling of left atrium. We hypothesized that radiofrequency ablation surgery for atrial fibrillation has a higher success rate and a lower recurrence rate of atrial fibrillation in patients with improved atrial stroma. This study is a multicenter, prospective, observational study conducted in China to evaluate whether sacubitril/valsartan can reduce atrial fibrillation recurrence rates, improve cardiac structure and function, and analyze the factors influencing the maintenance rate of sinus rhythm after atrial fibrillation ablation.

Background: Atrial fibrillation (AF) is associated with significant co-morbidities such as embolic stroke, heart failure, dementia. Consequently, AF poses a significant burden to the healthcare system, in both direct and indirect costs. The management of AF is complex, especially for patients with persistent AF. It is preferable to terminate the AF and restore normal sinus rhythm for relief of symptoms associated with AF or improvement of cardiac structure and function. The maintenance of AF, especially persist AF is associated with fibrosis of left atria. Furthermore, AF itself promotes fibrosis, which in turn leads to increased conduction heterogeneity within the atrial substrate resulting in further progression of AF. In animal models, alterations in myocytes after sustained AF resemble those of myocardial hibernation. Ultimately, these structural changes would lead to Calcium overload and metabolic stress, similar changes have been observed in humans. In humans, atrial dilatation and degenerative changes have been observed. Interstitial fibrosis is the prime cause of structural remodeling in left atrium. Whether reversal of sinus rhythm can reverse fibrosis partly? The introduction of Late Gadolinium enhancement magnetic resonance imaging (LGE-MRI) sequence now allows for non-invasive and dynamic assessment of the location and extent of atrial fibrosis. The investigators propose to evaluate whether sacubitril/valsartan can reduce atrial fibrillation recurrence rates, improve cardiac structure and function, and analyze the factors influencing the maintenance rate of sinus rhythm after atrial fibrillation ablation. Objectives: Primary: In patients with persistent atrial fibrillation and left atrial enlargement, the first part: after drug or electrical cardioversion, on the basis of using amiodarone to maintain sinus rhythm, they were divided into the group prescribed sacubitril/valsartan and the control group, and evaluated whether sacubitril/valsartan could reduce the recurrence rate of atrial fibrillation, improve cardiac structure and function, and improve atrial fibrosis by comparing the maintenance rate of sinus rhythm after cardioversion, ultrasound assessment of atrial structure and function, cardiac MRI evaluation of cardiac structure, function and fibrosis. The second part: Combined with the patient's wishes, researchers perform annular pulmonary vein isolation 3 to 6 months after cardioversion, evaluate the patient's sinus rhythm maintenance rate and cardiac structure and function at 3 months, 6 months, 1 year and 2 years after ablation. Then we will evaluate whether the improvement of atrial structure and function before surgery can predict the success rate of surgery, and evaluate whether sacubitril/valsartan further improves the success rate of surgery compared with the control group. If the number of patients in the subgroup is sufficient, subgroup analysis can be performed in a specific patient subgroup。 Secondary: We will assess the effects on patients with the following outcomes, including: analysis of other factors influencing left atrial remodeling. The influencing factors will be analyze of sinus rhythm maintenance rate after other electrical cardioversion.If the number of patients in the subgroup is sufficient, subgroup analysis can be performed in a specific subgroup of patients