Treadmill testing improves survival prediction models in pulmonary arterial hypertension

Background: Six-minute walk distance (6MWD) is used in the REVEAL equation to predict 1-year survival for patients with pulmonary arterial hypertension. We sought to determine whether exercise treadmill testing (ETT) could be used in its place. Methods: This was a single-center study in which 449 patients were enrolled. The variables predictive of survival in the REVEAL equation were evaluated and compared with survival predicted by the REVEAL equation without an exercise measure and a revised equation using ETT. Results: The addition of ETT to the equation improved the predictive ability of the REVEAL equation in the high- and low-risk patient groups. Conclusion: The study findings suggest that the addition of ETT parameters to the REVEAL prognostic equation improves the predictive value of the equation when 6-minute walk distance is unavailable.