Pressure Wave Velocity in the Human Aorta*

Abstract

After introduction of a catheter into the aorta, the pressure wave velocity was measured in 26 subjects whose ages ranged from 9 to 68 years. The first site of registration was approximately 10 cm from the aortic valve, and the second was 50 cm distal to the first. At both sites the time difference was measured between the R‐wave of the electrocardiogram and the foot of the pressure wave (TProx. and TDist.). The time difference T50 (TDist. – TProx.) and the distance between the sites of registration (50 cm) were used for the calculation of the pressure wave velocity (PWV). Four of the 26 subjects were normal; the others had some form of heart disease, including disease of the valves, hypertension and aortic atherosclerosis. Nevertheless, the values found for pressure wave velocity were in agreement with those stated in literature. A significant correlation was found between T50 and age (r = —0.788), between T50 and the proximal systolic blood pressure (r = −0.537), and between T50 and the proximal pulse pressure (r = −0.491), but not between T50 and the cardiac output and peripheral arterial resistance. There was no correlation between the proximal diastolic blood pressure and T50, possibly owing to the fact that all the patients had a diastolic blood pressure below 100 mm Hg. There was no significant difference between the coefficient of correlation for T50 and age (−0.788) and the multiple coefficient of correlation for T50 and age and systolic blood pressure proximal in the aorta (−0.811). Four patients had arteriographic aortic atherosclerosis. Two of these had lower T50 values than would be expected according to the proximal systolic blood pressure and the pulse pressure, but after exercise the values were within the normal range (±2 s.d.) Owing to the dominating influence of age on T50 and the considerable spreading of these values, it is not likely that the determination of pulse wave velocity will be of clinical value, for example, in the diagnosis of atherosclerosis.

Carotid‐femoral Pulse Wave Velocity*

“…Thus in groups in which no patient has a systolic blood pressure above 250 mm, it appears that age has the dominating influence on pulse wave velocity. The exclusion of the 2 patients made the data on systolic blood pressure and pulse pressure comparable with the data on 26 patients in whom we previously measured the pressure wave velocity by means of an intra‐arterial technique and from which exactly the same conclusions (3) were drawn. The conflicting results in the literature on the influence of the systolic blood pressure on the pulse wave velocity therefore can possibly be explained by differences in the blood pressure levels of the groups under study.…”

“…We have previously reported (in this issue of the Journal) our results with the determination of the pressure wave velocity in the aorta (3). After the insertion of a catheter the time difference was measured between the R‐wave of the electrocardiogram and the foot of the pressure wave, the pressure wave being first recorded approximately 10 cm distally from the aortic valve, and then (after retracting the catheter) 50 cm distally from the first point of measurement.…”

Speculations on Vascular Changes With Age

“…The pulse wave velocity correlates with age and depends upon the diastolic pressure and the elasticity of the blood vessel (17, 48–51). Hallock (52) found that the aortic pulse wave velocity increased from 4.1 meters/second at age 5 years, to 10.5 meters/second at age 65.…”

“…The pulse wave velocity correlates with age and depends upon the diastolic pressure and the elasticity of the blood vessel (17,(48)(49)(50)(51)…”