6MWT in Heart Failure
Exercise intolerance, along with dyspnea, fatigue are cardinal symptoms of heart failure, which adversely impact quality of life of the patient. Exercise improves well-being in heart failure. ESC (2016) and AHA/ACC (2013) heart failure guidelines recommend exercise to improve functional capacity, QOL and also to reduce the risk of hospitalization in stable HF patients (Class IA).
The 6-minute walk test assesses functional capacity or exercise tolerance in patients with heart failure and defines prognosis.
A 6-minute walk distance less than 200 m indicates lower functional capacity and carries a poor prognosis. If the walk distance is more than 500 m, the prognosis is good. If the 6-minute walk distance ranges between 200m and 500 m, patient can continue to exercise with oxygen supplementation.
Oxygen saturation during 6MWT also has prognostic significance. A fall in oxygen saturation (SpO2) during 6MWT of more than 4% indicates significant desaturation and is a predictor of mortality.
The aim should be to increase exercise tolerance even if with oxygen supplementation.