Determinants of Effort Intolerance in Patients With Heart Failure

The purpose of this study was to assess individual mechanisms of effort intolerance in patients with heart failure with preserved ejection fraction (HFpEF), heart failure with reduced ejection fraction (HFrEF), or normal cardiac function using combined echocardiography and cardiopulmonary stress testing.Combined stress echocardiography and cardiopulmonary tests visualize cardiac chambers in 4 well-defined activity levels (rest, unloaded,...