Exercise capacity before and after cardiac valve surgery.

Exercise stress testing and right-heart catheterization were carried out in 131 patients before and 6 months after cardiac valve surgery. The exercise capacity increased only a little in patients with mitral or double-valve surgery. In contrast, most patients with an aortic valve replacement had good exercise performance after surgery. Corresponding to the reduced exercise capacity most of the patients also had disturbed hemodynamics after surgery, with an elevated mean pulmonary artery pressure at rest, that raised inappropriately during exercise, and a diminished cardiac output at rest, that failed to increase during exercise, in relation to oxygen uptake.