Integrating six-minute walk distance into a simple multimarker score improves risk stratification in advanced HFrEF
M Chudy, M Lesny, E GoncalvesovaAbstract
Background
Six-minute walk distance (6MWD) is a widely used marker of functional capacity in heart failure, yet its integration with routine clinical variables for bedside risk stratification remains insufficient.
Purpose
To evaluate whether integrating 6MWD into a simple multimarker score improves prediction of 1-year all-cause mortality or LVAD implantation in patients with HFrEF.
Methods
We prospectively followed 450 HFrEF patients (mean age 51.9±10.1 years; mean LVEF 25.9±6.6%; median NT-proBNP 1676 [731–3448] ng/L). Heart transplantation recipients were excluded. The primary endpoint was 1-year all-cause mortality or LVAD implantation. A simple score integrated functional capacity (6MWD <415 m, 2 points) with NT-proBNP >1000 ng/L (2 points), LVEF <30% (1 point), and systolic blood pressure <100 mmHg (1 point). Cox regression, Kaplan-Meier and ROC analyses were performed.
Results
When analysed as a continuous variable, the score showed strong association with the endpoint (HR per 1-point increase 2.40, 95% CI 1.85–3.11). Patients were stratified into low (0–1 points, n=101), intermediate (2–3 points, n=202), and high-risk groups (4–6 points, n=147) with event rates of 0%, 4.95%, and 22.45%, respectively (log-rank p<0.001). Kaplan-Meier curves demonstrated clear stepwise risk separation (Picture 1). The score showed good discrimination (AUC 0.82), indicating that integration of 6MWD improves risk stratification beyond individual markers.
Conclusion
Integrating functional capacity into a pragmatic multimarker score enables effective short-term risk stratification in HFrEF. Incorporation of 6MWD identifies a very-low-risk group and a markedly high-risk phenotype, supporting its role in bedside decision-making and referral to advanced heart failure therapies.