Oxygen uptake and cardiac output at rest and during exercise after surgery for coarctation of the aorta.

Oxygen uptake and cardiac output at rest and during exercise were studied in 19 men operated on for coarctation of the aorta during childhood. Their aerobic capacity and their maximal values for cardiac output, stroke volume and arteriovenous oxygen difference were normal. No differences were found regarding these variables between hypertensive and normotensive subjects. Thus, there was no sign of failure of the left ventricle even in patients with high blood pressure during exercise. Whether the normal arteriovenous oxygen difference indicates a normal distribution of the cardiac output cannot be settled from the present data.