Impact of serial changes in cardiac hemodynamics on exercise performance in patients with heart failure due to ischemic and nonischemic cardiomyopathy

Although prior studies have examined the role of central and peripheral hemodynamics on exercise tolerance within populations of patients with heart failure, a clear relation between hemodynamics and exercise has not been demonstrated. This may be due to the inability to control for other factors that may influence exercise performance. To isolate the impact of hemodynamics on exercise, we studied the relation between changes in these factors within individual patients studied on 2 occasions. A consecutive series of 133 ambulatory patients with heart failure were evaluated on 2 separate occasions with right-sided cardiac catheterization and treadmill cardiopulmonary exercise testing. Linear regression models were constructed and correlation coefficients were determined to examine the relation between changes in hemodynamic variables and changes in exercise variables over time for each patient. A significant correlation between peak oxygen consumption (VO2) and pulmonary arterial wedge pressure was found for both the first (r = −0.316, p <0.001) and second (r = −0.183, p = 0.029) tests. A stronger inverse correlation between the change in pulmonary arterial wedge pressure and change in peak VO2 was observed in the study patients (r = −0.470, p <0.001). Similar correlations were found between change in peak VO2 and changes in pulmonary arterial pressures. Changes in left ventricular filling pressure influence exercise tolerance in patients with heart failure due to left ventricular systolic dysfunction. Interpretation of cardiopulmonary exercise testing for the purpose of determining cardiac transplantation eligibility will be improved with knowledge of left ventricular filling pressure.