Holter-Detected Arrhythmias in Acute Exacerbations of COPD: NT-proBNP Correlates and Hypercapnia Associated with COPD-Related Readmission

Background: Cardiac arrhythmias are increasingly recognized during acute exacerbations of chronic obstructive pulmonary disease (AECOPD), but their full spectrum and prognostic significance detected by continuous Holter monitoring remain insufficiently characterized. Methods: We conducted a single-center retrospective cohort study of patients hospitalized for AECOPD between April 2022 and January 2025 who underwent continuous Holter monitoring. Arrhythmias were classified as atrial arrhythmias (AA), atrial fibrillation/flutter (AF/AFL), ventricular arrhythmias (VA), or coexistence of ≥ 2 arrhythmia types. Multivariable regression models were used to identify factors associated with arrhythmias and clinical outcomes. COPD-related readmission was assessed using Kaplan–Meier and Cox regression analyses. Results: Among 548 patients, 60.4% experienced at least one arrhythmia during hospitalization. AA (37.6%) was the most frequent subtype, followed by VA (31.0%) and AF/AFL (12.2%), while 21.5% exhibited multiple arrhythmia types. Older age, male sex, higher heart rate, elevated NT-proBNP, and larger left atrial diameter were independently associated with in-hospital arrhythmias. NT-proBNP was consistently associated with all arrhythmia phenotypes and demonstrated moderate discrimination for arrhythmia identification (AUC=0.730; cutoff, 131.5 pg/mL). AF/AFL was independently associated with prolonged hospitalization (adjusted ratio=1.26, P =0.010). After accounting for the time-dependent effect of age, hypercapnia (PaCO 2 ≥ 45 mmHg) remained associated with a higher risk of COPD-related readmission (adjusted HR=1.85, 95% CI 1.19– 2.88; P =0.007). Conclusion: In-hospital arrhythmias are highly prevalent among patients hospitalized for AECOPD. NT-proBNP is consistently associated with multiple arrhythmia phenotypes and may aid arrhythmic risk stratification. Hypercapnia, but not arrhythmia status, remained independently associated with COPD-related readmission despite the limited sample and observational design.