Six-Minute Walk Distance-derived Estimated Peak Oxygen Uptake as a Supplementary Reference for Exercise Prescription in Pulmonary Arterial Hypertension: A Case Report

Six-minute walking distance (6MWD) is widely used to assess functional capacity and prognosis in patients with pulmonary arterial hypertension (PAH), but its use for exercise intensity prescription remains limited when cardiopulmonary exercise testing (CPET) is unavailable.A 21-year-old man with PAH was referred to an outpatient cardiac rehabilitation program after undergoing a six-minute walk test without CPET data.The 6MWD was used to estimate peak oxygen uptake (VO 2 ) using a previously published equation.Exercise intensity was then prescribed at 40%-59% of the estimated oxygen uptake reserve.The patient performed supervised aerobic exercise within the target intensity range, with close monitoring of symptoms, perceived exertion, oxygen saturation, and clinical responses, and exercise was terminated according to predefined criteria.This case report describes a practical approach using 6MWD-derived estimated peak VO 2 as a supplementary reference for individualized exercise prescription when direct CPET measurement is unavailable.