Prognostic impact of workload in patients with congestive heart failure

Recent data underline the prognostic value of cardiopulmonary exercise parameters (eg, peak oxygen consumption [PVO2]), percentage of predicted oxygen consumption [ppVO2], ventilation, and workload) in patients with congestive heart failure. These parameters were not yet compared in a multivariate analysis.

To detect the superiority of one of these parameters, in a prospective 1-year follow-up study we investigated 226 patients with heart failure. The end point of the study was combined death and prioritization for urgent cardiac transplantation within 1 year. Cardiopulmonary exercise testing was performed with evaluation of peak oxygen consumption, percentage of predicted peak oxygen consumption, peak carbon dioxide production, ventilation, workload, anaerobic threshold, and ventilation/carbon dioxide production ratio. All variables were univariate predictors of 1-year mortality and urgent transplantation. Multivariate analysis demonstrated that only workload and ventilation were independently related to 1-year mortality and urgent cardiac transplantation, whereas peak oxygen consumption or percentage of predicted peak oxygen consumption did not reach statistical significance in this model.

Workload on bicycle stress test correlates to 1-year mortality. More important, workload is a more powerful predictor of 1-year survival compared with established markers such as pVO2 or ppVO2.