6MWD Risk Stratification (Pulmonary Hypertension)

6MWD Risk Stratification in Pulmonary Hypertension: Explanation and Clinical Context The 6-minute walk distance (6MWD) is a simple, non-invasive functional test widely used in the assessment of patients with pulmonary arterial hypertension (PAH). It reflects exercise capacity, correlates with hemodynamic severity, and predicts prognosis. Low risk is defined as >440 meters, indicating preserved functional capacity and low 1-year mortality risk.

Intermediate risk (165–440 meters) reflects moderate functional impairment with an estimated 1-year mortality of 5–10%. High risk (<165 meters) is associated with severe functional limitation and a higher risk of adverse outcomes (>10% 1-year mortality). This stratification assists clinicians in guiding therapy intensity, follow-up frequency, and evaluating response to treatment.