Cross-Sectional Study on Electrocardiographic Disorders in Patients with Ankylosing Spondylitis in Real-World Conditions.

Background/Objectives: Ankylosing spondylitis (AS) has been associated with various comorbidities, including cardiovascular morbidity. Recent studies suggest that certain arrhythmias may be more frequent in AS patients than in the general population. The aim of this study was to analyze the prevalence of electric heart disorders (EHD) in patients with AS in real-world conditions and compare them with those reported in the general population. Methods: Descriptive cross-sectional study aiming to determine the prevalence of EHD in AS in pre-COVID-19 period. EHD were analyzed in a resting ECG and 24 h Holter monitoring. Additionally, the association between clinical and demographic variables was analyzed. Results: Among 121 patients with AS (62% men; mean ± SD age 54.6 ± 15.6 years; median [IQR] disease duration 14 (8-20) years), 18.2% presented any EHD, including 9.1% with supraventricular tachyarrhythmias (SVT) (5% atrial fibrillation [AF]) and 7.4% with atrioventricular block (AVB). Clinically relevant disorders (≥2nd-degree AVB or SVT) were observed in 9.9% of patients. In adjusted analyses, SVT was independently associated with older age and higher BMI, while any conduction delay and clinically relevant EHD were associated with age, hypertension, and disease-modifying antirheumatic-drug treatment duration. Comparisons with previous population-based studies showed similar data, with a non-significant trend toward higher AF prevalence in AS patients. Conclusions: There appears to be a trend toward a higher prevalence of arrhythmias in patients with AS in real-world conditions, which could have clinical and therapeutic implications. An association between EHD and pro-inflammatory conditions such as age and BMI was observed, supporting the hypothesis that underlying inflammation might contribute to increased arrhythmogenicity.