Edelmann et al 2011 did a RTof patients with heart failure with preserved ejection fraction. This is interesting, as few therapies exist for this population. Over a period of 3 months one group received standard care while another got standard care plus exercise. The exercise was a strength and endurance protocol focused on slightly raising the VO2max.
They found that peak VO2 increased and VO2max increased, confidence increased, left arterial volume decreased and quality of life as measured by the SF36 increased. Thus investing in an exercise regimen for those with heart failure would be a worthwhile investment and merits further study.