Comprehensive assessment of gastrointestinal status in patients with atrial fibrillation receiving direct oral anticoagulants: the REGATA Study

Natalya M. Vorobyeva , Irina P. Malaya , Vadim D. Zakiev , Antonina A. Masharova , Tatiana P. Pinchuk , Irina V. Kostomarova , Valentina S. Ostapenko , Yulia V. Kotovskaya , Olga N. Tkacheva

For citation:

Abstract

Objective. To describe the clinical characteristics of patients with atrial fibrillation (AF) who receive direct oral anticoagulants (DOAC) and to present the initial results of the REGATA trial regarding the baseline (prior to gastroprotective therapy) comprehensive clinical and instrumental assessment of the gastrointestinal (GI) tract.

Materials and methods. The REGATA study, a single-center, open-label, prospective, randomized, comparative controlled trial, enrolled 210 patients aged from 45 to 84 years (median age 71 years; 69% female). Patients were randomized into three groups (n=70 each): 1) rebamipide (Rebagit®) (100 mg tid); 2) pantoprazole (40 mg qd); 3) combination therapy with rebamipide and pantoprazole. The duration of gastroprotective therapy was 24 weeks. At baseline (prior to gastroprotective therapy), all patients underwent a comprehensive GI assessment, including gastrointestinal bleeding (GIB) risk evaluation, GI medical history, frequency of GI symptoms and dyspepsia severity (using GOS questionnaire), Helicobacter pylori testing, esophagogastroduodenoscopy (EGD) with Lanza scale scoring, fecal occult blood testing, and measurements of fecal calprotectin and zonulin levels.

Results. High frequency of GI symptoms (87%) and comorbid GI pathology (81%) was identified, with 91% of patients meeting high-risk criteria for GIB. EGD revealed no pathology in only 1% of cases; the most common findings were gastritis, reflux esophagitis, and mucosal atrophy. H. pylori infection was detected in 65% of patients. Positive fecal occult blood tests were observed in 19% of patients. Fecal calprotectin ranged from 30 to 867 µg/g (median 150, Q1; Q3 – 76; 212) and exceeded normal values in 72% of patients. Fecal zonulin ranged from 39 to 1295 ng/ml (median 393, Q1; Q3 – 200; 619) and was elevated in 92% of patients.

Conclusion. In patients with long-standing AF receiving DOAC, a comprehensive clinical and instrumental GI assessment was performed for the first time in combination with simultaneous evaluation of fecal calprotectin and zonulin levels.

Keywords: atrial fibrillation, direct oral anticoagulants, gastrointestinal tract, esophagogastroduodenoscopy, fecal calprotectin, zonulin.

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For citation:Vorobyeva N.M., Malaya I.P., Zakiev V.D., Masharova A.A., Pinchuk T.P., Kostomarova I.V., Ostapenko V.S., Kotovskaya Yu.V., Tkacheva O.N. Comprehensive assessment of gastrointestinal status in patients with atrial fibrillation receiving direct oral anticoagulants: the REGATA Study. Clinical review for general practice. 2026; 7 (7): 91–102 (In Russ.). DOI: 10.47407/kr2026.7.7.00892

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Clinical review for general practice