Normal Peripheral Pulses Research Articles

Upstroke time ratio: A new concept in differentiating valvular and subvalvular aortic stenosis

The upstroke time ratio is based on the relationship in duration and contour of the central and peripheral artery pressure curves. Although differing in contour, the normal central and peripheral arterial pulses show a constant relationship in the duration of their upstroke slopes. This relationship is altered by aortic valve and left ventricular outflow abnormality. The upstroke time ratio measures this difference and can, therefore, be used to differentiate between aortic and subaortic valvular stenosis. It is expressed as Radial artery corrected upstroke time Central aorta corrected upstroke time All studies were made during diagnostic cardiac catheterizations. Patients with involvment of any valve other than the aortic were not included in this study. The upstroke time ratio results were as follows: 12 normal subjects, 0.50 to 0.70; 12 with rheumatic aortic valvular stenosis, 0.80 to 0.87; 5 with congenital (bicuspid) valvular stenosis, 0.68 to 0.77; 4 with aortic subvalvular ring, 0.54 to 0.63; and 3 with idiopathic hypertrophy of left ventricular outflow tract, 1.0 to 1.2. The upstroke time ratio is useful in differentiating between aortic and subaortic stenosis and in diagnosing idiopathic hypertrophy with a subaortic fibrous stenosis. Other differential hemodynamic findings are mentioned.