Transcutaneous oxygen tension in the leg during exercise in patients with chronic cardiac failure

The transcutaneous partial pressure of oxygen measured in the lower limb was compared in 16 patients with chronic cardiac failure and seven normal subjects. At rest, there was no significant difference between patients and normals. At peak exercise, the partial pressure of oxygen fell significantly in those in heart failure, whereas no change was observed in normal subjects. No changes in arterial oxygen saturation (oximetry) were observed. These changes are likely to reflect abnormalities of peripheral perfusion of the skin.