Impact of cardiac rehabilitation on left atrial function in patients with heart failure reduced ejection fraction

Background Heart failure with reduced ejection fraction (HFrEF) involves impaired left ventricular systolic function and frequently affects left atrial (LA) performance, which plays a vital role in cardiac output and is an emerging prognostic marker. While cardiac rehabilitation (CR) improves overall cardiac function, its impact on LA function in HFrEF patients remains under-investigated. Objective To evaluate the effect of a structured 12-week CR program on LA function in patients with HFrEF. Methods This prospective observational cohort study included 40 patients with HFrEF (mean age 53.6 ± 10.2 years, 87.5% male), LVEF ≤ 40%, and NYHA class I–II. Participants underwent a 12-week supervised CR program comprising exercise and lifestyle modifications at Ain Shams University Hospitals. Two-dimensional speckle tracking echocardiography was used to assess LA reservoir, conduit, and contractile strain at baseline and post-rehabilitation. Patients with significant valvular disease, residual ischemia, non-sinus rhythm, or poor adherence were excluded. Results CR significantly improved LA strain parameters: reservoir strain increased from 20.5% ± 9.5 to 23.6% ± 8.0 (p = 0.004), conduit strain from –10.2% ± 6.0 to –11.6% ± 4.6 (p = 0.048), and contractile strain from –10.3% ± 5.8 to –12.0% ± 5.9 (p = 0.020). LVEF improved from 36.4% ± 3.5 to 40.7% ± 5.3 (p < 0.001), while changes in LA size and volume were minimal. Conclusion A 12-week CR program significantly enhances LA function in HFrEF, indicating potential benefits in atrial mechanics and overall cardiac performance. Larger studies are needed to validate long-term outcomes.