Correlation between aerobic functional capacity assessed by the one-minute sit-to-stand test and cardiopulmonary exercise testing in patients with heart failure with reduced ejection fraction

Introduction Heart failure with reduced ejection fraction (HFrEF) is characterised by left ventricular dysfunction, leading to impaired cardiac output and compromised tissue perfusion. This condition is associated with severe symptoms, significant functional limitations, an increased risk of hospitalisation, and high mortality rates. Exercise tolerance is a crucial marker of functional capacity in these patients, primarily due to impaired muscular oxygenation. Cardiopulmonary exercise testing (CPET) is considered the gold standard for assessing aerobic capacity; however, its high cost and technical complexity limit its widespread clinical use. The one-minute sit-to-stand test (1MSTS) has emerged as a simple, accessible, and easy-to-administer alternative for functional assessment. However, its correlation with CPET in patients with HFrEF remains insufficiently understood. Objective To investigate the relationship between aerobic functional capacity assessed by the 1MSTS and CPET in patients with HFrEF and to determine its correlation with functional parameters. Methods This cross-sectional study was approved by the Research Ethics Committee (protocol number: 6.954.577) and included 30 patients with HFrEF, divided into: Group 1: VO₂peak > 20 ml/kg/min (n=20) and Group 2: VO₂peak ≤ 20 ml/kg/min (n=10), Anthropometric data, physical activity level (International Physical Activity Questionnaire – IPAQ), and functional capacity perception (Duke Activity Status Index – DASI) were collected. Aerobic capacity was evaluated using the 1MSTS and CPET. Statistical analyses included Pearson and Spearman correlation tests, with a significance level of p<0.05. Results A high prevalence of physical inactivity was observed (63.33%, p=0.001). Group 2 exhibited a higher prevalence of diabetes (p=0.038) and lower DASI scores (p=0.047), indicating a worse perception of quality of life. In the 1MSTS, Group 1 completed a higher number of repetitions (22.7 vs. 18.9), although the difference was not statistically significant (p=0.089). Significant correlations were identified between: 1MSTS repetitions and VO₂peak from CPET (r = 0.384, p = 0.036), VO₂peak from CPET and VO₂ estimated from the 1MSTS (r = 0.467, p = 0.009) and DASI score and 1MSTS performance (r = 0.451, p = 0.012). These findings reinforce the clinical utility of the 1MSTS as a practical and functional indicator of aerobic capacity. Conclusion The 1MSTS demonstrated a significant association with peak functional capacity as measured by CPET and with perceived functional ability assessed by DASI. These results highlight its potential as a simple, accessible, and effective tool for aerobic functional assessment, particularly in resource-limited clinical settings.