The impact of atrial fibrillation on oxygen uptake and haemodynamics in patients with heart failure: a systematic review and meta-analysis.

Abstract

Aims: Atrial fibrillation (AF) may exacerbate exercise intolerance and haemodynamic limitations in individuals with heart failure (HF). Therefore, we performed a systematic search and meta-analysis to quantify the impact of AF on exercise tolerance (peak oxygen uptake, VO₂peak; primary outcome) and exercise haemodynamics (secondary outcomes) in patients with HF.

Methods and results: PubMed, Scopus, and Web of Science databases were systematically searched for articles from inception to June 2024. Studies were included if they: (i) examined participants with HF; (ii) compared participants with AF to those not in AF (i.e. sinus rhythm); (iii) measured VO₂peak from expired gas analysis. A fixed effects meta-analysis was performed, with groups compared using the weighted average effect size, represented as the weighted mean difference (WMD) with 95% confidence intervals (95% CI). Of 573 identified studies, 16 met the full inclusion comparing VO₂peak in HF-patients in AF [HF-AF; n = 1,271, 68% male, 67 years, left ventricular ejection fraction (LVEF): 41%], and HF in sinus rhythm (HF-SR; n = 4910; 62% male, 62 years, LVEF: 41%). VO₂peak was significantly lower in HF-AF (WMD: -1.55mL/kg/min, 95%-CI: -1.81 to -1.28, n = 6471). This coincided with a slightly lower peak heart rate (WMD: -2.94 b/min, 95%-CI: -4.76 to -1.13 b/min, n = 5115), decreased O₂pulse (WMD: -1.58 mL/beat, 95% CI: -1.90 to -1.26, n = 3049), and lower systolic blood pressure (WMD: -11.11 mmHg, 95% CI: -14.01 to -8.21, n = 2409).

Conclusion: In patients with HF, AF is associated with greater VO₂peak impairment, potentially due to reduced stroke volume and/or arterio-venous oxygen difference. This highlights the importance of combined strategies to identify and manage AF in individuals with HF.