Diagnostic Value of the First and Second Derivatives of the Arterial Pressure Pulse in Aortic Valve Disease and in

IT HAS been appreciated for many years that characteristic alterations in the con-figuration of the central and peripheral arterial pressure pulses occur in the presence of ab-normalities of the aortic valve, whether they are induced experimentally or occur in pa-tients with aortic valve disease.1--~- It is also recognized that the arterial pressure pulse is modified in patients with idiopathic hyper-trophic subaortic stenosis, although the changes that occur in this disease differ strik-ingly from those seen in patients with valvular aortic stenosis. 6-8 In the past, the characteriza-tion of arterial pressure pulses in patients with these lesions has consisted of descriptions of the pulse contour, determination of the pres-ence and position of the anacrotic and dicrotic notches, measurement of the duration of sys-tole and of the systolic upstroke time, and esti-mation of the slope of the pressure rise. In patients with severe valvular aortic stenosis, there is often prolongation of the total dura-tion of ejection and of the systolic upstroke time.9-13 Although the latter period is short-ened in patients with idiopathic hypertrophic subaortic stenosis, there is considerable over-lap in these measurements among various groups of patients and normal individuals.9 In order to derive more diagnostic informa-tion from the pressure pulse, some investigators have calculated the mean rate of arterial pres-sure rise by dividing the pulse pressure by the systolic upstroke time, or have estimated the slope of the pressure rise from the record-ed tracing.&quot