Predictors of isotonic exercise in patients with heart failure

Study aims were to determine the predictors of isotonic resistance exercise performance in patients with advanced heart failure and to compare the preexercise values of patients who experienced a negative physiologic response to resistance exercise with those who had minimal or no response.

A correlational design was used. After pharmacologic left ventricular unloading therapy using a pulmonary artery catheter, 34 patients with advanced heart failure performed graduated isotonic weight-lifting exercises. Measurements were made of hemodynamics and rating of perceived exertion after each test.

The following variables, measured at baseline, were significantly correlated with the amount of weight patients were able to lift: rating of perceived exertion (RPE; r = -0.42, P = 0.014); diastolic blood pressure (DBP; r = 0.49, P = 0.03); systolic blood pressure (SBP; r = 0.40, P = 0.017); pulmonary capillary wedge pressure (PCWP; r = 0.39, P = 0.026); and right atrial pressure (RAP; r = 0.35, P = 0.041). Multiple regression analysis, using a stepwise procedure, showed that 47% of the variance in exercise performance was explained by DBP, RPE, and PCWP. There were no significant differences in baseline hemodynamics, ejection fraction, or age between the group of patients who had a negative hemodynamic response at peak exercise and the group of patients who had minimal or no response.

Resting PCWP, DBP, and RPE can provide important information to help clinicians predict isotonic resistance exercise performance in patients with advanced heart failure. However, those patients who have a negative response to this type of exercise cannot be distinguished at baseline by clinical characteristics or age.