Evaluation of the effectiveness and safety of a novel substrate-based radiofrequency ablation for persistent atrial fibrillation: a prospective, randomised, parallel-controlled, single-blinded study protocol

INTRODUCTION

Pulmonary vein isolation (PVI) is the cornerstone of radiofrequency (RF) ablation for atrial fibrillation (AF). However, a single ablation strategy does not always achieve the desired therapeutic effect in all patients with persistent AF, and individualised strategies are required for different clinical characteristics.

METHODS AND ANALYSIS

This study aimed to determine the optimal catheter ablation strategy for persistent AF by comparing the efficacy of PVI and BCXL (BC: big circles encircling pulmonary vein isolation; XL: unfixed number of lines based on the left atrial substrate). The BCXL-AF study (clinical trial no. ChiCTR2200067081) was designed as a prospective, randomised, parallel-controlled, single-blinded clinical trial. Overall, 400 patients with persistent AF were randomised in a 1:1 ratio into PVI-only and BCXL-individualised ablation groups. Patients randomised to the individualised ablation group will be further categorised into risk strata according to their clinical condition using the actual ablation method determined by the strata. Seven postoperative visits were conducted from discharge to 24 months of age. The primary observation endpoint will be the incidence of atrial tachyarrhythmia (including AF, atrial flutter and atrial tachycardia with a duration of ≥30 s) without using antiarrhythmic drugs after a blank period of 3 months following a single ablation procedure. The BCXL-AF study will assess an optimal approach for persistent AF RF ablation and evaluate the effectiveness of individualised RF ablation strategies in reducing the recurrence rate of AF.

ETHICS AND DISSEMINATION

The study protocol was reviewed, and ethical approval was obtained from the Army Medical University Human Ethics Committee (approval number: 2022-484-01). All the participants provided written informed consent. This study was conducted according to the principles of the Declaration of Helsinki and its amendments. The results of this study will be disseminated through manuscript publication and conference presentations.

TRIAL REGISTRATION NUMBER

ChiCTR2200067081.

Long Non-Coding RNA ANRIL Regulates Inflammatory Factor Expression in Ulcerative Colitis Via the miR-191-5p/SATB1 Axis

Ulcerative colitis, an inflammatory bowel disease, manifests with symptoms such as abdominal pain, diarrhea, and mucopurulent feces. The long non-coding RNA (lncRNA) ANRIL exhibits significantly reduced expression in UC, yet its specific mechanism is unknown. This study revealed that ANRIL is involved in the progression of UC by inhibiting IL-6 and TNF-α via miR-191-5P/SATB1 axis. We found that in patients with UC, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were significantly overexpressed in inflamed colon sites, whereas ANRIL was significantly under-expressed and associated with disease severity. The downregulation of ANRIL resulted in the increased expression of IL-6 and TNF-α in LPS-treated FHCs. ANRIL directly targeted miR-191-5p, thereby inhibiting its expression and augmenting SATB1 expression. Moreover, overexpression of miR-191-5p abolished ANRIL-mediated inhibition of IL-6 and TNF-α production. Dual luciferase reporter assays revealed the specific binding of miR-191-5p to ANRIL and SATB1. Furthermore, the downregulation of ANRIL promoted DSS-induced colitis in mice. Together, we provide evidence that ANRIL plays a critical role in regulating IL-6 and TNF-α expression in UC by modulating the miR-191-5p/SATB1 axis. Our study provides novel insights into progression and molecular therapeutic strategies in UC.