New York Heart Association functional class predicts exercise parameters in the current era AMERICAN HEART JOURNAL Russell, S. D., Saval, M. A., Robbins, J. L., Ellestad, M. H., Gottlieb, S. S., Handberg, E. M., Zhou, Y., Chandler, B., HF-ACTION Investigators 2009; 158 (4): S24–S30


The New York Heart Association (NYHA) functional class is a subjective estimate of a patient's functional ability based on symptoms that do not always correlate with the objective estimate of functional capacity, peak oxygen consumption (peak V(O2)). In addition, relationships between these 2 measurements have not been examined in the current medical era when patients are using beta-blockers, aldosterone antagonists, and cardiac resynchronization therapy (CRT). Using baseline data from the HF-ACTION (Heart Failure and A Controlled Trial Investigating Outcomes of Exercise TraiNing) study, we examined this relationship.One thousand seven hundred fifty-eight patients underwent a symptom-limited metabolic stress test and stopped exercise due to dyspnea or fatigue. The relationship between NYHA functional class and peak V(O2) was examined. In addition, the effects of beta-blockers, aldosterone antagonists, and CRT therapy on these relationships were compared.The NYHA II patients have a significantly higher peak Vo(2) (16.1 +/- 4.6 vs 13.0 +/- 4.2 mL/kg per minute), a lower ventilation (Ve)/V(CO2) slope (32.8 +/- 7.7 vs 36.8 +/- 10.4), and a longer duration of exercise (11.0 +/- 3.9 vs 8.0 +/- 3.4 minutes) than NYHA III/IV patients. Within each functional class, there was no difference in any of the exercise parameters between patients on or off of beta-blockers, aldosterone antagonists, or CRT therapy. Finally, with increasing age, a significant difference in peak Vo(2), Ve/V(CO2) slope, and exercise time was found.For patients being treated with current medical therapy, there still is a difference in true functional capacity between NYHA functional class II and III/IV patients. However, within each NYHA functional class, the presence or absence or contemporary heart failure therapies does not alter exercise parameters.

View details for DOI 10.1016/j.ahj.2009.07.017

View details for Web of Science ID 000270705800004

View details for PubMedID 19782785

View details for PubMedCentralID PMC2762947